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python_feedgen09_jnboehm.com.atom.xml - sfeed_tests - sfeed tests and RSS and Atom files |
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python_feedgen09_jnboehm.com.atom.xml (142453B) |
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1 <?xml version='1.0' encoding='UTF-8'?> |
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2 <feed xmlns="http://www.w3.org/2005/Atom" xml:lang="en"><id>http://arxiv.org/</id><title>arxiv parsed</title><updated>2021-09-23T09:06:47.938938+00:00</updated><author><name>Jan Niklas Böhm</name><email>jan-niklas.boehm@uni-tuebingen.de</email></author><link href="http://arxiv.org" rel="alternate"/><link href="https://jnboehm.com" rel="self"/><generator uri="https://lkiesow.github.io/python-feedgen" version="0.9.0">python-feedgen</generator><subtitle>This parses the arxiv feed and filters interesting (to me) articles!</subtitle><entry><id>http://arxiv.org/abs/2109.09705</id><title>Neural forecasting at scale (update)</title><updated>2021-09-23T09:06:49.539266+00:00</updated><author><name>Philippe Chatigny</name></author><author><name>Shengrui Wang Jean-Marc Patenaude</name></author><author><name>Boris N. Oreshkin</name></author><link href="http://arxiv.org/abs/2109.09705" rel="alternate"/><summary>We study the problem of efficiently scaling ensemble-based deep neural |
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3 networks for time series (TS) forecasting on a large set of time series. |
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4 Current state-of-the-art deep ensemble models have high memory and |
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5 computational requirements, hampering their use to forecast millions of TS in |
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6 practical scenarios. We propose N-BEATS(P), a global multivariate variant of |
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7 the N-BEATS model designed to allow simultaneous training of multiple |
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8 univariate TS forecasting models. Our model addresses the practical limitations |
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9 of related models, reducing the training time by half and memory requirement by |
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10 a factor of 5, while keeping the same level of accuracy. We have performed |
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11 multiple experiments detailing the various ways to train our model and have |
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12 obtained results that demonstrate its capacity to support zero-shot TS |
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13 forecasting, i.e., to train a neural network on a source TS dataset and deploy |
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14 it on a different target TS dataset without retraining, which provides an |
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15 efficient and reliable solution to forecast at scale even in difficult |
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16 forecasting conditions. |
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17 </summary></entry><entry><id>http://arxiv.org/abs/2109.02624</id><title>Functional additive regression on shape and form manifolds of planar curves (update)</title><updated>2021-09-23T09:06:49.538917+00:00</updated><author><name>Almond Stöcker</name></author><author><name>Sonja Greven</name></author><link href="http://arxiv.org/abs/2109.02624" rel="alternate"/><summary>Defining shape and form as equivalence classes under translation, rotation |
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18 and -- for shapes -- also scale, we extend generalized additive regression to |
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19 models for the shape/form of planar curves or landmark configurations. The |
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20 model respects the resulting quotient geometry of the response, employing the |
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21 squared geodesic distance as loss function and a geodesic response function |
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22 mapping the additive predictor to the shape/form space. For fitting the model, |
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23 we propose a Riemannian $L_2$-Boosting algorithm well-suited for a potentially |
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24 large number of possibly parameter-intensive model terms, which also yiels |
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25 automated model selection. We provide novel intuitively interpretable |
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26 visualizations for (even non-linear) covariate effects in the shape/form space |
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27 via suitable tensor based factorizations. The usefulness of the proposed |
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28 framework is illustrated in an analysis of 1) astragalus shapes of wild and |
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29 domesticated sheep and 2) cell forms generated in a biophysical model, as well |
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30 as 3) in a realistic simulation study with response shapes and forms motivated |
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31 from a dataset on bottle outlines. |
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32 </summary></entry><entry><id>http://arxiv.org/abs/2107.04136</id><title>Diagonal Nonlinear Transformations Preserve Structure in Covariance and Precision Matrices (update)</title><updated>2021-09-23T09:06:49.538501+00:00</updated><author><name>Rebecca E Morrison</name></author><author><name>Ricardo Baptista</name></author><author><name>Estelle L Basor</name></author><link href="http://arxiv.org/abs/2107.04136" rel="alternate"/><summary>For a multivariate normal distribution, the sparsity of the covariance and |
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33 precision matrices encodes complete information about independence and |
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34 conditional independence properties. For general distributions, the covariance |
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35 and precision matrices reveal correlations and so-called partial correlations |
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36 between variables, but these do not, in general, have any correspondence with |
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37 respect to independence properties. In this paper, we prove that, for a certain |
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38 class of non-Gaussian distributions, these correspondences still hold, exactly |
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39 for the covariance and approximately for the precision. The distributions -- |
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40 sometimes referred to as "nonparanormal" -- are given by diagonal |
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41 transformations of multivariate normal random variables. We provide several |
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42 analytic and numerical examples illustrating these results. |
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43 </summary></entry><entry><id>http://arxiv.org/abs/2106.09370</id><title>A deep generative model for probabilistic energy forecasting in power systems: normalizing flows (update)</title><updated>2021-09-23T09:06:49.538071+00:00</updated><author><name>Jonathan Dumas</name></author><author><name>Antoine Wehenkel Damien Lanaspeze</name></author><author><name>Bertrand Cornélusse</name></author><author><name>Antonio Sutera</name></author><link href="http://arxiv.org/abs/2106.09370" rel="alternate"/><summary>Greater direct electrification of end-use sectors with a higher share of |
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44 renewables is one of the pillars to power a carbon-neutral society by 2050. |
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45 However, in contrast to conventional power plants, renewable energy is subject |
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46 to uncertainty raising challenges for their interaction with power systems. |
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47 Scenario-based probabilistic forecasting models have become a vital tool to |
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48 equip decision-makers. This paper presents to the power systems forecasting |
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49 practitioners a recent deep learning technique, the normalizing flows, to |
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50 produce accurate scenario-based probabilistic forecasts that are crucial to |
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51 face the new challenges in power systems applications. The strength of this |
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52 technique is to directly learn the stochastic multivariate distribution of the |
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53 underlying process by maximizing the likelihood. Through comprehensive |
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54 empirical evaluations using the open data of the Global Energy Forecasting |
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55 Competition 2014, we demonstrate that this methodology is competitive with |
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56 other state-of-the-art deep learning generative models: generative adversarial |
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57 networks and variational autoencoders. The models producing weather-based wind, |
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58 solar power, and load scenarios are properly compared in terms of forecast |
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59 value by considering the case study of an energy retailer and quality using |
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60 several complementary metrics. The numerical experiments are simple and easily |
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61 reproducible. Thus, we hope it will encourage other forecasting practitioners |
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62 to test and use normalizing flows in power system applications such as bidding |
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63 on electricity markets, scheduling power systems with high renewable energy |
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64 sources penetration, energy management of virtual power plan or microgrids, and |
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65 unit commitment. |
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66 </summary></entry><entry><id>http://arxiv.org/abs/2105.14367</id><title>Deconvolutional Density Network: Modeling Free-Form Conditional Distributions (update)</title><updated>2021-09-23T09:06:49.537668+00:00</updated><author><name>Bing Chen</name></author><author><name>Mazharul Islam</name></author><author><name>Jisuo Gao</name></author><author><name>Lin Wang</name></author><link href="http://arxiv.org/abs/2105.14367" rel="alternate"/><summary>Conditional density estimation (CDE) is the task of estimating the |
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67 probability of an event conditioned on some inputs. A neural network (NN) can |
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68 be used to compute the output distribution for continuous-domain, but it is |
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69 difficult to explicitly approximate a free-form one without knowing the |
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70 information of its general form a priori. In order to fit an arbitrary |
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71 conditional distribution, discretizing the continuous domain into bins is an |
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72 effective strategy, as long as we have sufficiently narrow bins and very large |
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73 data. However, collecting enough data is often hard to reach and falls far |
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74 short of that ideal in many circumstances, especially in multivariate CDE for |
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75 the curse of dimensionality. In this paper, we demonstrate the benefits of |
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76 modeling free-form conditional distributions using a deconvolution-based neural |
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77 net framework, coping with data deficiency problems in discretization. It has |
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78 the advantage of being flexible but also takes advantage of the hierarchical |
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79 smoothness offered by the deconvolution layers. We compare our method to a |
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80 number of other density-estimation approaches and show that our Deconvolutional |
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81 Density Network (DDN) outperforms the competing methods on many univariate and |
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82 multivariate tasks. |
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83 </summary></entry><entry><id>http://arxiv.org/abs/2102.07767</id><title>Communication-efficient Distributed Cooperative Learning with Compressed Beliefs (update)</title><updated>2021-09-23T09:06:49.537320+00:00</updated><author><name>Mohammad Taha Toghani</name></author><author><name>César A. Uribe</name></author><link href="http://arxiv.org/abs/2102.07767" rel="alternate"/><summary>We study the problem of distributed cooperative learning, where a group of |
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84 agents seeks to agree on a set of hypotheses that best describes a sequence of |
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85 private observations. In the scenario where the set of hypotheses is large, we |
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86 propose a belief update rule where agents share compressed (either sparse or |
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87 quantized) beliefs with an arbitrary positive compression rate. Our algorithm |
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88 leverages a unified communication rule that enables agents to access |
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89 wide-ranging compression operators as black-box modules. We prove the almost |
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90 sure asymptotic exponential convergence of beliefs around the set of optimal |
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91 hypotheses. Additionally, we show a non-asymptotic, explicit, and linear |
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92 concentration rate in probability of the beliefs on the optimal hypothesis set. |
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93 We provide numerical experiments to illustrate the communication benefits of |
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94 our method. The simulation results show that the number of transmitted bits can |
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95 be reduced to 5-10% of the non-compressed method in the studied scenarios. |
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96 </summary></entry><entry><id>http://arxiv.org/abs/2012.15059</id><title>Ensembles of Localised Models for Time Series Forecasting (update)</title><updated>2021-09-23T09:06:49.536891+00:00</updated><author><name>Rakshitha Godahewa</name></author><author><name>Kasun Bandara</name></author><author><name>Geoffrey I. Webb</name></author><author><name>Slawek Smyl</name></author><author><name>Christoph Bergmeir</name></author><link href="http://arxiv.org/abs/2012.15059" rel="alternate"/><summary>With large quantities of data typically available nowadays, forecasting |
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97 models that are trained across sets of time series, known as Global Forecasting |
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98 Models (GFM), are regularly outperforming traditional univariate forecasting |
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99 models that work on isolated series. As GFMs usually share the same set of |
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100 parameters across all time series, they often have the problem of not being |
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101 localised enough to a particular series, especially in situations where |
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102 datasets are heterogeneous. We study how ensembling techniques can be used with |
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103 generic GFMs and univariate models to solve this issue. Our work systematises |
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104 and compares relevant current approaches, namely clustering series and training |
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105 separate submodels per cluster, the so-called ensemble of specialists approach, |
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106 and building heterogeneous ensembles of global and local models. We fill some |
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107 gaps in the existing GFM localisation approaches, in particular by |
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108 incorporating varied clustering techniques such as feature-based clustering, |
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109 distance-based clustering and random clustering, and generalise them to use |
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110 different underlying GFM model types. We then propose a new methodology of |
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111 clustered ensembles where we train multiple GFMs on different clusters of |
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112 series, obtained by changing the number of clusters and cluster seeds. Using |
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113 Feed-forward Neural Networks, Recurrent Neural Networks, and Pooled Regression |
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114 models as the underlying GFMs, in our evaluation on eight publicly available |
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115 datasets, the proposed models are able to achieve significantly higher accuracy |
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116 than baseline GFM models and univariate forecasting methods. |
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117 </summary></entry><entry><id>http://arxiv.org/abs/2009.13267</id><title>Energy-Based Reranking: Improving Neural Machine Translation Using Energy-Based Models (update)</title><updated>2021-09-23T09:06:49.536440+00:00</updated><author><name>Sumanta Bhattacharyya</name></author><author><name>Amirmohammad Rooshenas</name></author><author><name>Subhajit Naskar</name></author><author><name>Simeng Sun</name></author><author><name>Mohit Iyyer</name></author><author><name>Andrew McCallum</name></author><link href="http://arxiv.org/abs/2009.13267" rel="alternate"/><summary>The discrepancy between maximum likelihood estimation (MLE) and task measures |
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118 such as BLEU score has been studied before for autoregressive neural machine |
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119 translation (NMT) and resulted in alternative training algorithms (Ranzato et |
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120 al., 2016; Norouzi et al., 2016; Shen et al., 2016; Wu et al., 2018). However, |
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121 MLE training remains the de facto approach for autoregressive NMT because of |
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122 its computational efficiency and stability. Despite this mismatch between the |
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123 training objective and task measure, we notice that the samples drawn from an |
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124 MLE-based trained NMT support the desired distribution -- there are samples |
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125 with much higher BLEU score comparing to the beam decoding output. To benefit |
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126 from this observation, we train an energy-based model to mimic the behavior of |
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127 the task measure (i.e., the energy-based model assigns lower energy to samples |
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128 with higher BLEU score), which is resulted in a re-ranking algorithm based on |
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129 the samples drawn from NMT: energy-based re-ranking (EBR). We use both marginal |
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130 energy models (over target sentence) and joint energy models (over both source |
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131 and target sentences). Our EBR with the joint energy model consistently |
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132 improves the performance of the Transformer-based NMT: +4 BLEU points on |
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133 IWSLT'14 German-English, +3.0 BELU points on Sinhala-English, +1.2 BLEU on |
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134 WMT'16 English-German tasks. |
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135 </summary></entry><entry><id>http://arxiv.org/abs/2005.11079</id><title>Graph Random Neural Network for Semi-Supervised Learning on Graphs (update)</title><updated>2021-09-23T09:06:49.535864+00:00</updated><author><name>Wenzheng Feng</name></author><author><name>Jie Zhang</name></author><author><name>Yuxiao Dong</name></author><author><name>Yu Han</name></author><author><name>Huanbo Luan</name></author><author><name>Qian Xu</name></author><author><name>Qiang Yang</name></author><author><name>Evgeny Kharlamov</name></author><author><name>Jie Tang</name></author><link href="http://arxiv.org/abs/2005.11079" rel="alternate"/><summary>We study the problem of semi-supervised learning on graphs, for which graph |
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136 neural networks (GNNs) have been extensively explored. However, most existing |
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137 GNNs inherently suffer from the limitations of over-smoothing, non-robustness, |
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138 and weak-generalization when labeled nodes are scarce. In this paper, we |
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139 propose a simple yet effective framework -- GRAPH RANDOM NEURAL NETWORKS |
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140 (GRAND) -- to address these issues. In GRAND, we first design a random |
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141 propagation strategy to perform graph data augmentation. Then we leverage |
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142 consistency regularization to optimize the prediction consistency of unlabeled |
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143 nodes across different data augmentations. Extensive experiments on graph |
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144 benchmark datasets suggest that GRAND significantly outperforms |
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145 state-of-the-art GNN baselines on semi-supervised node classification. Finally, |
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146 we show that GRAND mitigates the issues of over-smoothing and non-robustness, |
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147 exhibiting better generalization behavior than existing GNNs. The source code |
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148 of GRAND is publicly available at https://github.com/Grand20/grand. |
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149 </summary></entry><entry><id>http://arxiv.org/abs/2004.14427</id><title>Whittle index based Q-learning for restless bandits with average reward (update)</title><updated>2021-09-23T09:06:49.535532+00:00</updated><author><name>Konstantin E. Avrachenkov</name></author><author><name>Vivek S. Borkar</name></author><link href="http://arxiv.org/abs/2004.14427" rel="alternate"/><summary>A novel reinforcement learning algorithm is introduced for multiarmed |
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150 restless bandits with average reward, using the paradigms of Q-learning and |
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151 Whittle index. Specifically, we leverage the structure of the Whittle index |
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152 policy to reduce the search space of Q-learning, resulting in major |
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153 computational gains. Rigorous convergence analysis is provided, supported by |
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154 numerical experiments. The numerical experiments show excellent empirical |
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155 performance of the proposed scheme. |
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156 </summary></entry><entry><id>http://arxiv.org/abs/2003.05738</id><title>IG-RL: Inductive Graph Reinforcement Learning for Massive-Scale Traffic Signal Control (update)</title><updated>2021-09-23T09:06:49.535152+00:00</updated><author><name>François-Xavier Devailly</name></author><author><name>Denis Larocque</name></author><author><name>Laurent Charlin</name></author><link href="http://arxiv.org/abs/2003.05738" rel="alternate"/><summary>Scaling adaptive traffic-signal control involves dealing with combinatorial |
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157 state and action spaces. Multi-agent reinforcement learning attempts to address |
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158 this challenge by distributing control to specialized agents. However, |
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159 specialization hinders generalization and transferability, and the |
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160 computational graphs underlying neural-networks architectures -- dominating in |
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161 the multi-agent setting -- do not offer the flexibility to handle an arbitrary |
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162 number of entities which changes both between road networks, and over time as |
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163 vehicles traverse the network. We introduce Inductive Graph Reinforcement |
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164 Learning (IG-RL) based on graph-convolutional networks which adapts to the |
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165 structure of any road network, to learn detailed representations of |
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166 traffic-controllers and their surroundings. Our decentralized approach enables |
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167 learning of a transferable-adaptive-traffic-signal-control policy. After being |
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168 trained on an arbitrary set of road networks, our model can generalize to new |
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169 road networks, traffic distributions, and traffic regimes, with no additional |
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170 training and a constant number of parameters, enabling greater scalability |
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171 compared to prior methods. Furthermore, our approach can exploit the |
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172 granularity of available data by capturing the (dynamic) demand at both the |
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173 lane and the vehicle levels. The proposed method is tested on both road |
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174 networks and traffic settings never experienced during training. We compare |
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175 IG-RL to multi-agent reinforcement learning and domain-specific baselines. In |
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176 both synthetic road networks and in a larger experiment involving the control |
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177 of the 3,971 traffic signals of Manhattan, we show that different |
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178 instantiations of IG-RL outperform baselines. |
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179 </summary></entry><entry><id>http://arxiv.org/abs/1905.10029</id><title>Power up! Robust Graph Convolutional Network via Graph Powering (update)</title><updated>2021-09-23T09:06:49.534750+00:00</updated><author><name>Ming Jin</name></author><author><name>Heng Chang</name></author><author><name>Wenwu Zhu</name></author><author><name>Somayeh Sojoudi</name></author><link href="http://arxiv.org/abs/1905.10029" rel="alternate"/><summary>Graph convolutional networks (GCNs) are powerful tools for graph-structured |
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180 data. However, they have been recently shown to be vulnerable to topological |
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181 attacks. To enhance adversarial robustness, we go beyond spectral graph theory |
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182 to robust graph theory. By challenging the classical graph Laplacian, we |
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183 propose a new convolution operator that is provably robust in the spectral |
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184 domain and is incorporated in the GCN architecture to improve expressivity and |
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185 interpretability. By extending the original graph to a sequence of graphs, we |
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186 also propose a robust training paradigm that encourages transferability across |
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187 graphs that span a range of spatial and spectral characteristics. The proposed |
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188 approaches are demonstrated in extensive experiments to simultaneously improve |
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189 performance in both benign and adversarial situations. |
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190 </summary></entry><entry><id>http://arxiv.org/abs/2109.10319</id><title>Consistency of spectral clustering for directed network community detection</title><updated>2021-09-23T09:06:49.534381+00:00</updated><author><name>Huan Qing</name></author><author><name>Jingli Wang</name></author><link href="http://arxiv.org/abs/2109.10319" rel="alternate"/><summary>Directed networks appear in various areas, such as biology, sociology, |
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191 physiology and computer science. However, at present, most network analysis |
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192 ignores the direction. In this paper, we construct a spectral clustering method |
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193 based on the singular decomposition of the adjacency matrix to detect community |
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194 in directed stochastic block model (DiSBM). By considering a sparsity |
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195 parameter, under some mild conditions, we show the proposed approach can |
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196 consistently recover hidden row and column communities for different scaling of |
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197 degrees. |
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198 </summary></entry><entry><id>http://arxiv.org/abs/2109.10298</id><title>Assured Neural Network Architectures for Control and Identification of Nonlinear Systems</title><updated>2021-09-23T09:06:49.534036+00:00</updated><author><name>James Ferlez</name></author><author><name>Yasser Shoukry</name></author><link href="http://arxiv.org/abs/2109.10298" rel="alternate"/><summary>In this paper, we consider the problem of automatically designing a Rectified |
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199 Linear Unit (ReLU) Neural Network (NN) architecture (number of layers and |
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200 number of neurons per layer) with the assurance that it is sufficiently |
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201 parametrized to control a nonlinear system; i.e. control the system to satisfy |
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202 a given formal specification. This is unlike current techniques, which provide |
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203 no assurances on the resultant architecture. Moreover, our approach requires |
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204 only limited knowledge of the underlying nonlinear system and specification. We |
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205 assume only that the specification can be satisfied by a Lipschitz-continuous |
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206 controller with a known bound on its Lipschitz constant; the specific |
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207 controller need not be known. From this assumption, we bound the number of |
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208 affine functions needed to construct a Continuous Piecewise Affine (CPWA) |
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209 function that can approximate any Lipschitz-continuous controller that |
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210 satisfies the specification. Then we connect this CPWA to a NN architecture |
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211 using the authors' recent results on the Two-Level Lattice (TLL) NN |
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212 architecture; the TLL architecture was shown to be parameterized by the number |
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213 of affine functions present in the CPWA function it realizes. |
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214 </summary></entry><entry><id>http://arxiv.org/abs/2109.10279</id><title>Multiblock-Networks: A Neural Network Analog to Component Based Methods for Multi-Source Data</title><updated>2021-09-23T09:06:49.533577+00:00</updated><author><name>Anna Jenul</name></author><author><name>Stefan Schrunner</name></author><author><name>Runar Helin</name></author><author><name>Kristian Hovde Liland</name></author><author><name>Cecilia Marie Futsæther</name></author><author><name>Oliver Tomic</name></author><link href="http://arxiv.org/abs/2109.10279" rel="alternate"/><summary>Training predictive models on datasets from multiple sources is a common, yet |
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215 challenging setup in applied machine learning. Even though model interpretation |
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216 has attracted more attention in recent years, many modeling approaches still |
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217 focus mainly on performance. To further improve the interpretability of machine |
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218 learning models, we suggest the adoption of concepts and tools from the |
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219 well-established framework of component based multiblock analysis, also known |
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220 as chemometrics. Nevertheless, artificial neural networks provide greater |
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221 flexibility in model architecture and thus, often deliver superior predictive |
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222 performance. In this study, we propose a setup to transfer the concepts of |
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223 component based statistical models, including multiblock variants of principal |
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224 component regression and partial least squares regression, to neural network |
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225 architectures. Thereby, we combine the flexibility of neural networks with the |
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226 concepts for interpreting block relevance in multiblock methods. In two use |
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227 cases we demonstrate how the concept can be implemented in practice, and |
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228 compare it to both common feed-forward neural networks without blocks, as well |
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229 as statistical component based multiblock methods. Our results underline that |
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230 multiblock networks allow for basic model interpretation while matching the |
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231 performance of ordinary feed-forward neural networks. |
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232 </summary></entry><entry><id>http://arxiv.org/abs/2109.10262</id><title>Generalized Optimization: A First Step Towards Category Theoretic Learning Theory</title><updated>2021-09-23T09:06:49.533249+00:00</updated><author><name>Dan Shiebler</name></author><link href="http://arxiv.org/abs/2109.10262" rel="alternate"/><summary>The Cartesian reverse derivative is a categorical generalization of |
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233 reverse-mode automatic differentiation. We use this operator to generalize |
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234 several optimization algorithms, including a straightforward generalization of |
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235 gradient descent and a novel generalization of Newton's method. We then explore |
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236 which properties of these algorithms are preserved in this generalized setting. |
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237 First, we show that the transformation invariances of these algorithms are |
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238 preserved: while generalized Newton's method is invariant to all invertible |
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239 linear transformations, generalized gradient descent is invariant only to |
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240 orthogonal linear transformations. Next, we show that we can express the change |
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241 in loss of generalized gradient descent with an inner product-like expression, |
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242 thereby generalizing the non-increasing and convergence properties of the |
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243 gradient descent optimization flow. Finally, we include several numerical |
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244 experiments to illustrate the ideas in the paper and demonstrate how we can use |
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245 them to optimize polynomial functions over an ordered ring. |
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246 </summary></entry><entry><id>http://arxiv.org/abs/2109.10254</id><title>Uncertainty Toolbox: an Open-Source Library for Assessing, Visualizing, and Improving Uncertainty Quantification</title><updated>2021-09-23T09:06:49.532048+00:00</updated><author><name>Youngseog Chung</name></author><author><name>Ian Char</name></author><author><name>Han Guo</name></author><author><name>Jeff Schneider</name></author><author><name>Willie Neiswanger</name></author><link href="http://arxiv.org/abs/2109.10254" rel="alternate"/><summary>With increasing deployment of machine learning systems in various real-world |
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247 tasks, there is a greater need for accurate quantification of predictive |
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248 uncertainty. While the common goal in uncertainty quantification (UQ) in |
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249 machine learning is to approximate the true distribution of the target data, |
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250 many works in UQ tend to be disjoint in the evaluation metrics utilized, and |
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251 disparate implementations for each metric lead to numerical results that are |
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252 not directly comparable across different works. To address this, we introduce |
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253 Uncertainty Toolbox, an open-source python library that helps to assess, |
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254 visualize, and improve UQ. Uncertainty Toolbox additionally provides |
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255 pedagogical resources, such as a glossary of key terms and an organized |
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256 collection of key paper references. We hope that this toolbox is useful for |
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257 accelerating and uniting research efforts in uncertainty in machine learning. |
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258 </summary></entry><entry><id>http://arxiv.org/abs/2109.10219</id><title>Adaptive Reliability Analysis for Multi-fidelity Models using a Collective Learning Strategy</title><updated>2021-09-23T09:06:49.531656+00:00</updated><author><name>Chi Zhang</name></author><author><name>Chaolin Song</name></author><author><name>Abdollah Shafieezadeh</name></author><link href="http://arxiv.org/abs/2109.10219" rel="alternate"/><summary>In many fields of science and engineering, models with different fidelities |
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259 are available. Physical experiments or detailed simulations that accurately |
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260 capture the behavior of the system are regarded as high-fidelity models with |
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261 low model uncertainty, however, they are expensive to run. On the other hand, |
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262 simplified physical experiments or numerical models are seen as low-fidelity |
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263 models that are cheaper to evaluate. Although low-fidelity models are often not |
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264 suitable for direct use in reliability analysis due to their low accuracy, they |
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265 can offer information about the trend of the high-fidelity model thus providing |
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266 the opportunity to explore the design space at a low cost. This study presents |
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267 a new approach called adaptive multi-fidelity Gaussian process for reliability |
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268 analysis (AMGPRA). Contrary to selecting training points and information |
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269 sources in two separate stages as done in state-of-the-art mfEGRA method, the |
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270 proposed approach finds the optimal training point and information source |
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271 simultaneously using the novel collective learning function (CLF). CLF is able |
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272 to assess the global impact of a candidate training point from an information |
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273 source and it accommodates any learning function that satisfies a certain |
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274 profile. In this context, CLF provides a new direction for quantifying the |
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275 impact of new training points and can be easily extended with new learning |
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276 functions to adapt to different reliability problems. The performance of the |
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277 proposed method is demonstrated by three mathematical examples and one |
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278 engineering problem concerning the wind reliability of transmission towers. It |
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279 is shown that the proposed method achieves similar or higher accuracy with |
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280 reduced computational costs compared to state-of-the-art single and |
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281 multi-fidelity methods. A key application of AMGPRA is high-fidelity fragility |
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282 modeling using complex and costly physics-based computational models. |
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283 </summary></entry><entry><id>http://arxiv.org/abs/2109.10162</id><title>Learning low-degree functions from a logarithmic number of random queries</title><updated>2021-09-23T09:06:49.531322+00:00</updated><author><name>Alexandros Eskenazis</name></author><author><name>Paata Ivanisvili</name></author><link href="http://arxiv.org/abs/2109.10162" rel="alternate"/><summary>We prove that for any integer $n\in\mathbb{N}$, $d\in\{1,\ldots,n\}$ and any |
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284 $\varepsilon,\delta\in(0,1)$, a bounded function $f:\{-1,1\}^n\to[-1,1]$ of |
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285 degree at most $d$ can be learned with probability at least $1-\delta$ and |
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286 $L_2$-error $\varepsilon$ using $\log(\tfrac{n}{\delta})\,\varepsilon^{-d-1} |
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287 C^{d^{3/2}\sqrt{\log d}}$ random queries for a universal finite constant $C>1$. |
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288 </summary></entry><entry><id>http://arxiv.org/abs/2109.09988</id><title>Signal Classification using Smooth Coefficients of Multiple wavelets</title><updated>2021-09-23T09:06:49.530981+00:00</updated><author><name>Paul Grant</name></author><author><name>Md Zahidul Islam</name></author><link href="http://arxiv.org/abs/2109.09988" rel="alternate"/><summary>Classification of time series signals has become an important construct and |
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289 has many practical applications. With existing classifiers we may be able to |
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290 accurately classify signals, however that accuracy may decline if using a |
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291 reduced number of attributes. Transforming the data then undertaking reduction |
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292 in dimensionality may improve the quality of the data analysis, decrease time |
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293 required for classification and simplify models. We propose an approach, which |
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294 chooses suitable wavelets to transform the data, then combines the output from |
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295 these transforms to construct a dataset to then apply ensemble classifiers to. |
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296 We demonstrate this on different data sets, across different classifiers and |
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297 use differing evaluation methods. Our experimental results demonstrate the |
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298 effectiveness of the proposed technique, compared to the approaches that use |
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299 either raw signal data or a single wavelet transform. |
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300 </summary></entry><entry><id>http://arxiv.org/abs/2109.09859</id><title>Sharp global convergence guarantees for iterative nonconvex optimization: A Gaussian process perspective</title><updated>2021-09-23T09:06:49.530601+00:00</updated><author><name>Kabir Aladin Chandrasekher</name></author><author><name>Ashwin Pananjady</name></author><author><name>Christos Thrampoulidis</name></author><link href="http://arxiv.org/abs/2109.09859" rel="alternate"/><summary>We consider a general class of regression models with normally distributed |
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301 covariates, and the associated nonconvex problem of fitting these models from |
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302 data. We develop a general recipe for analyzing the convergence of iterative |
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303 algorithms for this task from a random initialization. In particular, provided |
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304 each iteration can be written as the solution to a convex optimization problem |
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305 satisfying some natural conditions, we leverage Gaussian comparison theorems to |
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306 derive a deterministic sequence that provides sharp upper and lower bounds on |
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307 the error of the algorithm with sample-splitting. Crucially, this deterministic |
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308 sequence accurately captures both the convergence rate of the algorithm and the |
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309 eventual error floor in the finite-sample regime, and is distinct from the |
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310 commonly used "population" sequence that results from taking the |
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311 infinite-sample limit. We apply our general framework to derive several |
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312 concrete consequences for parameter estimation in popular statistical models |
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313 including phase retrieval and mixtures of regressions. Provided the sample size |
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314 scales near-linearly in the dimension, we show sharp global convergence rates |
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315 for both higher-order algorithms based on alternating updates and first-order |
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316 algorithms based on subgradient descent. These corollaries, in turn, yield |
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317 multiple consequences, including: (a) Proof that higher-order algorithms can |
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318 converge significantly faster than their first-order counterparts (and |
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319 sometimes super-linearly), even if the two share the same population update and |
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320 (b) Intricacies in super-linear convergence behavior for higher-order |
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321 algorithms, which can be nonstandard (e.g., with exponent 3/2) and sensitive to |
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322 the noise level in the problem. We complement these results with extensive |
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323 numerical experiments, which show excellent agreement with our theoretical |
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324 predictions. |
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325 </summary></entry><entry><id>http://arxiv.org/abs/2109.09856</id><title>SFFDD: Deep Neural Network with Enriched Features for Failure Prediction with Its Application to Computer Disk Driver</title><updated>2021-09-23T09:06:49.530264+00:00</updated><author><name>Lanfa Frank Wang</name></author><author><name>Danjue Li</name></author><link href="http://arxiv.org/abs/2109.09856" rel="alternate"/><summary>A classification technique incorporating a novel feature derivation method is |
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326 proposed for predicting failure of a system or device with multivariate time |
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327 series sensor data. We treat the multivariate time series sensor data as images |
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328 for both visualization and computation. Failure follows various patterns which |
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329 are closely related to the root causes. Different predefined transformations |
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330 are applied on the original sensors data to better characterize the failure |
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331 patterns. In addition to feature derivation, ensemble method is used to further |
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332 improve the performance. In addition, a general algorithm architecture of deep |
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333 neural network is proposed to handle multiple types of data with less manual |
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334 feature engineering. We apply the proposed method on the early predict failure |
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335 of computer disk drive in order to improve storage systems availability and |
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336 avoid data loss. The classification accuracy is largely improved with the |
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337 enriched features, named smart features. |
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338 </summary></entry><entry><id>http://arxiv.org/abs/2109.09855</id><title>Reinforcement Learning for Finite-Horizon Restless Multi-Armed Multi-Action Bandits</title><updated>2021-09-23T09:06:49.529889+00:00</updated><author><name>Guojun Xiong</name></author><author><name>Jian Li</name></author><author><name>Rahul Singh</name></author><link href="http://arxiv.org/abs/2109.09855" rel="alternate"/><summary>We study a finite-horizon restless multi-armed bandit problem with multiple |
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339 actions, dubbed R(MA)^2B. The state of each arm evolves according to a |
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340 controlled Markov decision process (MDP), and the reward of pulling an arm |
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341 depends on both the current state of the corresponding MDP and the action |
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342 taken. The goal is to sequentially choose actions for arms so as to maximize |
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343 the expected value of the cumulative rewards collected. Since finding the |
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344 optimal policy is typically intractable, we propose a computationally appealing |
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345 index policy which we call Occupancy-Measured-Reward Index Policy. Our policy |
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346 is well-defined even if the underlying MDPs are not indexable. We prove that it |
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347 is asymptotically optimal when the activation budget and number of arms are |
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348 scaled up, while keeping their ratio as a constant. For the case when the |
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349 system parameters are unknown, we develop a learning algorithm. Our learning |
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350 algorithm uses the principle of optimism in the face of uncertainty and further |
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351 uses a generative model in order to fully exploit the structure of |
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352 Occupancy-Measured-Reward Index Policy. We call it the R(MA)^2B-UCB algorithm. |
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353 As compared with the existing algorithms, R(MA)^2B-UCB performs close to an |
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354 offline optimum policy, and also achieves a sub-linear regret with a low |
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355 computational complexity. Experimental results show that R(MA)^2B-UCB |
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356 outperforms the existing algorithms in both regret and run time. |
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357 </summary></entry><entry><id>http://arxiv.org/abs/2109.09847</id><title>Fast TreeSHAP: Accelerating SHAP Value Computation for Trees</title><updated>2021-09-23T09:06:49.529569+00:00</updated><author><name>Jilei Yang</name></author><link href="http://arxiv.org/abs/2109.09847" rel="alternate"/><summary>SHAP (SHapley Additive exPlanation) values are one of the leading tools for |
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358 interpreting machine learning models, with strong theoretical guarantees |
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359 (consistency, local accuracy) and a wide availability of implementations and |
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360 use cases. Even though computing SHAP values takes exponential time in general, |
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361 TreeSHAP takes polynomial time on tree-based models. While the speedup is |
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362 significant, TreeSHAP can still dominate the computation time of industry-level |
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363 machine learning solutions on datasets with millions or more entries, causing |
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364 delays in post-hoc model diagnosis and interpretation service. In this paper we |
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365 present two new algorithms, Fast TreeSHAP v1 and v2, designed to improve the |
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366 computational efficiency of TreeSHAP for large datasets. We empirically find |
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367 that Fast TreeSHAP v1 is 1.5x faster than TreeSHAP while keeping the memory |
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368 cost unchanged. Similarly, Fast TreeSHAP v2 is 2.5x faster than TreeSHAP, at |
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369 the cost of a slightly higher memory usage, thanks to the pre-computation of |
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370 expensive TreeSHAP steps. We also show that Fast TreeSHAP v2 is well-suited for |
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371 multi-time model interpretations, resulting in as high as 3x faster explanation |
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372 of newly incoming samples. |
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373 </summary></entry><entry><id>http://arxiv.org/abs/2109.09831</id><title>SMAC3: A Versatile Bayesian Optimization Package for Hyperparameter Optimization</title><updated>2021-09-23T09:06:49.529020+00:00</updated><author><name>Marius Lindauer</name></author><author><name>Katharina Eggensperger</name></author><author><name>Matthias Feurer</name></author><author><name>André Biedenkapp</name></author><author><name>Difan Deng</name></author><author><name>Carolin Benjamins</name></author><author><name>René Sass</name></author><author><name>Frank Hutter</name></author><link href="http://arxiv.org/abs/2109.09831" rel="alternate"/><summary>Algorithm parameters, in particular hyperparameters of machine learning |
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374 algorithms, can substantially impact their performance. To support users in |
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375 determining well-performing hyperparameter configurations for their algorithms, |
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376 datasets and applications at hand, SMAC3 offers a robust and flexible framework |
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377 for Bayesian Optimization, which can improve performance within a few |
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378 evaluations. It offers several facades and pre-sets for typical use cases, such |
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379 as optimizing hyperparameters, solving low dimensional continuous (artificial) |
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380 global optimization problems and configuring algorithms to perform well across |
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381 multiple problem instances. The SMAC3 package is available under a permissive |
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382 BSD-license at https://github.com/automl/SMAC3. |
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383 </summary></entry><entry><id>http://arxiv.org/abs/2109.09816</id><title>Deviation-Based Learning</title><updated>2021-09-23T09:06:49.528686+00:00</updated><author><name>Junpei Komiyama</name></author><author><name>Shunya Noda</name></author><link href="http://arxiv.org/abs/2109.09816" rel="alternate"/><summary>We propose deviation-based learning, a new approach to training recommender |
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384 systems. In the beginning, the recommender and rational users have different |
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385 pieces of knowledge, and the recommender needs to learn the users' knowledge to |
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386 make better recommendations. The recommender learns users' knowledge by |
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387 observing whether each user followed or deviated from her recommendations. We |
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388 show that learning frequently stalls if the recommender always recommends a |
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389 choice: users tend to follow the recommendation blindly, and their choices do |
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390 not reflect their knowledge. Social welfare and the learning rate are improved |
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391 drastically if the recommender abstains from recommending a choice when she |
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392 predicts that multiple arms will produce a similar payoff. |
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393 </summary></entry><entry><id>http://arxiv.org/abs/2011.02602</id><title>Merchant Category Identification Using Credit Card Transactions</title><updated>2021-09-23T09:06:49.528234+00:00</updated><author><name>Chin-Chia Michael Yeh</name></author><author><name>Zhongfang Zhuang</name></author><author><name>Yan Zheng</name></author><author><name>Liang Wang</name></author><author><name>Junpeng Wang</name></author><author><name>Wei Zhang</name></author><link href="http://arxiv.org/abs/2011.02602" rel="alternate"/><summary>Digital payment volume has proliferated in recent years with the rapid growth |
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394 of small businesses and online shops. When processing these digital |
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395 transactions, recognizing each merchant's real identity (i.e., business type) |
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396 is vital to ensure the integrity of payment processing systems. Conventionally, |
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397 this problem is formulated as a time series classification problem solely using |
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398 the merchant transaction history. However, with the large scale of the data, |
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399 and changing behaviors of merchants and consumers over time, it is extremely |
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400 challenging to achieve satisfying performance from off-the-shelf classification |
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401 methods. In this work, we approach this problem from a multi-modal learning |
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402 perspective, where we use not only the merchant time series data but also the |
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403 information of merchant-merchant relationship (i.e., affinity) to verify the |
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404 self-reported business type (i.e., merchant category) of a given merchant. |
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405 Specifically, we design two individual encoders, where one is responsible for |
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406 encoding temporal information and the other is responsible for affinity |
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407 information, and a mechanism to fuse the outputs of the two encoders to |
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408 accomplish the identification task. Our experiments on real-world credit card |
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409 transaction data between 71,668 merchants and 433,772,755 customers have |
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410 demonstrated the effectiveness and efficiency of the proposed model. |
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411 </summary></entry><entry><id>http://arxiv.org/abs/2007.05303</id><title>Multi-future Merchant Transaction Prediction</title><updated>2021-09-23T09:06:49.527829+00:00</updated><author><name>Chin-Chia Michael Yeh</name></author><author><name>Zhongfang Zhuang</name></author><author><name>Wei Zhang</name></author><author><name>Liang Wang</name></author><link href="http://arxiv.org/abs/2007.05303" rel="alternate"/><summary>The multivariate time series generated from merchant transaction history can |
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412 provide critical insights for payment processing companies. The capability of |
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413 predicting merchants' future is crucial for fraud detection and recommendation |
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414 systems. Conventionally, this problem is formulated to predict one multivariate |
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415 time series under the multi-horizon setting. However, real-world applications |
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416 often require more than one future trend prediction considering the |
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417 uncertainties, where more than one multivariate time series needs to be |
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418 predicted. This problem is called multi-future prediction. In this work, we |
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419 combine the two research directions and propose to study this new problem: |
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420 multi-future, multi-horizon and multivariate time series prediction. This |
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421 problem is crucial as it has broad use cases in the financial industry to |
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422 reduce the risk while improving user experience by providing alternative |
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423 futures. This problem is also challenging as now we not only need to capture |
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424 the patterns and insights from the past but also train a model that has a |
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425 strong inference capability to project multiple possible outcomes. To solve |
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426 this problem, we propose a new model using convolutional neural networks and a |
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427 simple yet effective encoder-decoder structure to learn the time series pattern |
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428 from multiple perspectives. We use experiments on real-world merchant |
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429 transaction data to demonstrate the effectiveness of our proposed model. We |
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430 also provide extensive discussions on different model design choices in our |
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431 experimental section. |
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432 </summary></entry><entry><id>http://arxiv.org/abs/2109.09690</id><title>Trust Your Robots! Predictive Uncertainty Estimation of Neural Networks with Sparse Gaussian Processes (update)</title><updated>2021-09-23T09:06:49.527407+00:00</updated><author><name>Jongseok Lee</name></author><author><name>Jianxiang Feng</name></author><author><name>Matthias Humt</name></author><author><name>Marcus G. Müller</name></author><author><name>Rudolph Triebel</name></author><link href="http://arxiv.org/abs/2109.09690" rel="alternate"/><summary>This paper presents a probabilistic framework to obtain both reliable and |
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433 fast uncertainty estimates for predictions with Deep Neural Networks (DNNs). |
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434 Our main contribution is a practical and principled combination of DNNs with |
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435 sparse Gaussian Processes (GPs). We prove theoretically that DNNs can be seen |
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436 as a special case of sparse GPs, namely mixtures of GP experts (MoE-GP), and we |
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437 devise a learning algorithm that brings the derived theory into practice. In |
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438 experiments from two different robotic tasks -- inverse dynamics of a |
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439 manipulator and object detection on a micro-aerial vehicle (MAV) -- we show the |
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440 effectiveness of our approach in terms of predictive uncertainty, improved |
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441 scalability, and run-time efficiency on a Jetson TX2. We thus argue that our |
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442 approach can pave the way towards reliable and fast robot learning systems with |
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443 uncertainty awareness. |
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444 </summary></entry><entry><id>http://arxiv.org/abs/2109.09658</id><title>FUTURE-AI: Guiding Principles and Consensus Recommendations for Trustworthy Artificial Intelligence in Future Medical Imaging (update)</title><updated>2021-09-23T09:06:49.526638+00:00</updated><author><name>Karim Lekadir</name></author><author><name>Richard Osuala</name></author><author><name>Catherine Gallin</name></author><author><name>Noussair Lazrak</name></author><author><name>Kaisar Kushibar</name></author><author><name>Gianna Tsakou</name></author><author><name>Susanna Aussó</name></author><author><name>Leonor Cerdá Alberich</name></author><author><name>Konstantinos Marias</name></author><author><name>Manolis Tskinakis</name></author><author><name>Sara Colantonio</name></author><author><name>Nickolas Papanikolaou</name></author><author><name>Zohaib Salahuddin</name></author><author><name>Henry C Woodruff</name></author><author><name>Philippe Lambin</name></author><author><name>Luis Martí-Bonmatí</name></author><link href="http://arxiv.org/abs/2109.09658" rel="alternate"/><summary>The recent advancements in artificial intelligence (AI) combined with the |
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445 extensive amount of data generated by today's clinical systems, has led to the |
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446 development of imaging AI solutions across the whole value chain of medical |
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447 imaging, including image reconstruction, medical image segmentation, |
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448 image-based diagnosis and treatment planning. Notwithstanding the successes and |
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449 future potential of AI in medical imaging, many stakeholders are concerned of |
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450 the potential risks and ethical implications of imaging AI solutions, which are |
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451 perceived as complex, opaque, and difficult to comprehend, utilise, and trust |
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452 in critical clinical applications. Despite these concerns and risks, there are |
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453 currently no concrete guidelines and best practices for guiding future AI |
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454 developments in medical imaging towards increased trust, safety and adoption. |
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455 To bridge this gap, this paper introduces a careful selection of guiding |
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456 principles drawn from the accumulated experiences, consensus, and best |
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457 practices from five large European projects on AI in Health Imaging. These |
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458 guiding principles are named FUTURE-AI and its building blocks consist of (i) |
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459 Fairness, (ii) Universality, (iii) Traceability, (iv) Usability, (v) Robustness |
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460 and (vi) Explainability. In a step-by-step approach, these guidelines are |
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461 further translated into a framework of concrete recommendations for specifying, |
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462 developing, evaluating, and deploying technically, clinically and ethically |
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463 trustworthy AI solutions into clinical practice. |
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464 </summary></entry><entry><id>http://arxiv.org/abs/2109.09105</id><title>What BERT Based Language Models Learn in Spoken Transcripts: An Empirical Study (update)</title><updated>2021-09-23T09:06:49.526265+00:00</updated><author><name>Ayush Kumar</name></author><author><name>Mukuntha Narayanan Sundararaman</name></author><author><name>Jithendra Vepa</name></author><link href="http://arxiv.org/abs/2109.09105" rel="alternate"/><summary>Language Models (LMs) have been ubiquitously leveraged in various tasks |
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465 including spoken language understanding (SLU). Spoken language requires careful |
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466 understanding of speaker interactions, dialog states and speech induced |
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467 multimodal behaviors to generate a meaningful representation of the |
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468 conversation. In this work, we propose to dissect SLU into three representative |
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469 properties:conversational (disfluency, pause, overtalk), channel (speaker-type, |
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470 turn-tasks) and ASR (insertion, deletion,substitution). We probe BERT based |
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471 language models (BERT, RoBERTa) trained on spoken transcripts to investigate |
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472 its ability to understand multifarious properties in absence of any speech |
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473 cues. Empirical results indicate that LM is surprisingly good at capturing |
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474 conversational properties such as pause prediction and overtalk detection from |
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475 lexical tokens. On the downsides, the LM scores low on turn-tasks and ASR |
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476 errors predictions. Additionally, pre-training the LM on spoken transcripts |
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477 restrain its linguistic understanding. Finally, we establish the efficacy and |
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478 transferability of the mentioned properties on two benchmark datasets: |
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479 Switchboard Dialog Act and Disfluency datasets. |
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480 </summary></entry><entry><id>http://arxiv.org/abs/2109.07436</id><title>Synthesizing Policies That Account For Human Execution Errors Caused By State-Aliasing In Markov Decision Processes (update)</title><updated>2021-09-23T09:06:49.525891+00:00</updated><author><name>Sriram Gopalakrishnan</name></author><author><name>Mudit Verma</name></author><author><name>Subbarao Kambhampati</name></author><link href="http://arxiv.org/abs/2109.07436" rel="alternate"/><summary>When humans are given a policy to execute, there can be policy execution |
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481 errors and deviations in execution if there is uncertainty in identifying a |
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482 state. So an algorithm that computes a policy for a human to execute ought to |
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483 consider these effects in its computations. An optimal MDP policy that is |
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484 poorly executed (because of a human agent) maybe much worse than another policy |
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485 that is executed with fewer errors. In this paper, we consider the problems of |
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486 erroneous execution and execution delay when computing policies for a human |
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487 agent that would act in a setting modeled by a Markov Decision Process. We |
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488 present a framework to model the likelihood of policy execution errors and |
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489 likelihood of non-policy actions like inaction (delays) due to state |
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490 uncertainty. This is followed by a hill climbing algorithm to search for good |
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491 policies that account for these errors. We then use the best policy found by |
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492 hill climbing with a branch and bound algorithm to find the optimal policy. We |
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493 show experimental results in a Gridworld domain and analyze the performance of |
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494 the two algorithms. We also present human studies that verify if our |
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495 assumptions on policy execution by humans under state-aliasing are reasonable. |
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496 </summary></entry><entry><id>http://arxiv.org/abs/2109.01134</id><title>Learning to Prompt for Vision-Language Models (update)</title><updated>2021-09-23T09:06:49.525484+00:00</updated><author><name>Kaiyang Zhou</name></author><author><name>Jingkang Yang</name></author><author><name>Chen Change Loy</name></author><author><name>Ziwei Liu</name></author><link href="http://arxiv.org/abs/2109.01134" rel="alternate"/><summary>Vision-language pre-training has recently emerged as a promising alternative |
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497 for representation learning. It shifts from the tradition of using images and |
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498 discrete labels for learning a fixed set of weights, seen as visual concepts, |
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499 to aligning images and raw text for two separate encoders. Such a paradigm |
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500 benefits from a broader source of supervision and allows zero-shot transfer to |
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501 downstream tasks since visual concepts can be diametrically generated from |
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502 natural language, known as prompt. In this paper, we identify that a major |
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503 challenge of deploying such models in practice is prompt engineering. This is |
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504 because designing a proper prompt, especially for context words surrounding a |
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505 class name, requires domain expertise and typically takes a significant amount |
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506 of time for words tuning since a slight change in wording could have a huge |
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507 impact on performance. Moreover, different downstream tasks require specific |
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508 designs, further hampering the efficiency of deployment. To overcome this |
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509 challenge, we propose a novel approach named context optimization (CoOp). The |
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510 main idea is to model context in prompts using continuous representations and |
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511 perform end-to-end learning from data while keeping the pre-trained parameters |
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512 fixed. In this way, the design of task-relevant prompts can be fully automated. |
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513 Experiments on 11 datasets show that CoOp effectively turns pre-trained |
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514 vision-language models into data-efficient visual learners, requiring as few as |
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515 one or two shots to beat hand-crafted prompts with a decent margin and able to |
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516 gain significant improvements when using more shots (e.g., at 16 shots the |
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517 average gain is around 17% with the highest reaching over 50%). CoOp also |
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518 exhibits strong robustness to distribution shift. |
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|
519 </summary></entry><entry><id>http://arxiv.org/abs/2108.09432</id><title>ARAPReg: An As-Rigid-As Possible Regularization Loss for Learning Deformable Shape Generators (update)</title><updated>2021-09-23T09:06:49.525027+00:00</updated><author><name>Qixing Huang</name></author><author><name>Xiangru Huang</name></author><author><name>Bo Sun</name></author><author><name>Zaiwei Zhang</name></author><author><name>Junfeng Jiang</name></author><author><name>Chandrajit Bajaj</name></author><link href="http://arxiv.org/abs/2108.09432" rel="alternate"/><summary>This paper introduces an unsupervised loss for training parametric |
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|
520 deformation shape generators. The key idea is to enforce the preservation of |
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521 local rigidity among the generated shapes. Our approach builds on an |
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522 approximation of the as-rigid-as possible (or ARAP) deformation energy. We show |
|
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523 how to develop the unsupervised loss via a spectral decomposition of the |
|
|
|
524 Hessian of the ARAP energy. Our loss nicely decouples pose and shape variations |
|
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|
525 through a robust norm. The loss admits simple closed-form expressions. It is |
|
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|
526 easy to train and can be plugged into any standard generation models, e.g., |
|
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527 variational auto-encoder (VAE) and auto-decoder (AD). Experimental results show |
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528 that our approach outperforms existing shape generation approaches considerably |
|
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529 on public benchmark datasets of various shape categories such as human, animal |
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530 and bone. |
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|
531 </summary></entry><entry><id>http://arxiv.org/abs/2107.11913</id><title>Measuring Ethics in AI with AI: A Methodology and Dataset Construction (update)</title><updated>2021-09-23T09:06:49.524619+00:00</updated><author><name>Pedro H.C. Avelar</name></author><author><name>Rafael B. Audibert</name></author><author><name>Anderson R. Tavares</name></author><author><name>Luís C. Lamb</name></author><link href="http://arxiv.org/abs/2107.11913" rel="alternate"/><summary>Recently, the use of sound measures and metrics in Artificial Intelligence |
|
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|
532 has become the subject of interest of academia, government, and industry. |
|
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|
533 Efforts towards measuring different phenomena have gained traction in the AI |
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534 community, as illustrated by the publication of several influential field |
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|
535 reports and policy documents. These metrics are designed to help decision |
|
|
|
536 takers to inform themselves about the fast-moving and impacting influences of |
|
|
|
537 key advances in Artificial Intelligence in general and Machine Learning in |
|
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|
538 particular. In this paper we propose to use such newfound capabilities of AI |
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|
|
539 technologies to augment our AI measuring capabilities. We do so by training a |
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|
540 model to classify publications related to ethical issues and concerns. In our |
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|
|
541 methodology we use an expert, manually curated dataset as the training set and |
|
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|
542 then evaluate a large set of research papers. Finally, we highlight the |
|
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|
543 implications of AI metrics, in particular their contribution towards developing |
|
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|
544 trustful and fair AI-based tools and technologies. Keywords: AI Ethics; AI |
|
|
|
545 Fairness; AI Measurement. Ethics in Computer Science. |
|
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|
546 </summary></entry><entry><id>http://arxiv.org/abs/2107.04775</id><title>LS3: Latent Space Safe Sets for Long-Horizon Visuomotor Control of Sparse Reward Iterative Tasks (update)</title><updated>2021-09-23T09:06:49.524190+00:00</updated><author><name>Albert Wilcox</name></author><author><name>Ashwin Balakrishna</name></author><author><name>Brijen Thananjeyan</name></author><author><name>Joseph E. Gonzalez</name></author><author><name>Ken Goldberg</name></author><link href="http://arxiv.org/abs/2107.04775" rel="alternate"/><summary>Reinforcement learning (RL) has shown impressive success in exploring |
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547 high-dimensional environments to learn complex tasks, but can often exhibit |
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|
548 unsafe behaviors and require extensive environment interaction when exploration |
|
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|
549 is unconstrained. A promising strategy for learning in dynamically uncertain |
|
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550 environments is requiring that the agent can robustly return to learned safe |
|
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|
551 sets, where task success (and therefore safety) can be guaranteed. While this |
|
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552 approach has been successful in low-dimensions, enforcing this constraint in |
|
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553 environments with visual observations is exceedingly challenging. We present a |
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554 novel continuous representation for safe sets by framing it as a binary |
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555 classification problem in a learned latent space, which flexibly scales to |
|
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556 image observations. We then present a new algorithm, Latent Space Safe Sets |
|
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|
557 (LS3), which uses this representation for long-horizon tasks with sparse |
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558 rewards. We evaluate LS3 on 4 domains, including a challenging sequential |
|
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559 pushing task in simulation and a physical cable routing task. We find that LS3 |
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560 can use prior task successes to restrict exploration and learn more efficiently |
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561 than prior algorithms while satisfying constraints. See |
|
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562 https://tinyurl.com/latent-ss for code and supplementary material. |
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563 </summary></entry><entry><id>http://arxiv.org/abs/2106.07857</id><title>Bilateral Personalized Dialogue Generation with Contrastive Learning (update)</title><updated>2021-09-23T09:06:49.523794+00:00</updated><author><name>Bin Li</name></author><author><name>Hanjun Deng</name></author><link href="http://arxiv.org/abs/2106.07857" rel="alternate"/><summary>Generating personalized responses is one of the major challenges in natural |
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564 human-robot interaction. Current researches in this field mainly focus on |
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565 generating responses consistent with the robot's pre-assigned persona, while |
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566 ignoring the user's persona. Such responses may be inappropriate or even |
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567 offensive, which may lead to the bad user experience. Therefore, we propose a |
|
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568 Bilateral Personalized Dialogue Generation (BPDG) method for dyadic |
|
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569 conversation, which integrates user and robot personas into dialogue generation |
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570 via designing a dynamic persona-aware fusion method. To bridge the gap between |
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|
571 the learning objective function and evaluation metrics, the Conditional Mutual |
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|
572 Information Maximum (CMIM) criterion is adopted with contrastive learning to |
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573 select the proper response from the generated candidates. Moreover, a bilateral |
|
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574 persona accuracy metric is designed to measure the degree of bilateral |
|
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575 personalization. Experimental results demonstrate that, compared with several |
|
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576 state-of-the-art methods, the final results of the proposed method are more |
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577 personalized and consistent with bilateral personas in terms of both automatic |
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578 and manual evaluations. |
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579 </summary></entry><entry><id>http://arxiv.org/abs/2105.15033</id><title>DiaKG: an Annotated Diabetes Dataset for Medical Knowledge Graph Construction (update)</title><updated>2021-09-23T09:06:49.523206+00:00</updated><author><name>Dejie Chang</name></author><author><name>Mosha Chen</name></author><author><name>Chaozhen Liu</name></author><author><name>Liping Liu</name></author><author><name>Dongdong Li</name></author><author><name>Wei Li</name></author><author><name>Fei Kong</name></author><author><name>Bangchang Liu</name></author><author><name>Xiaobin Luo</name></author><author><name>Ji Qi</name></author><author><name>Qiao Jin</name></author><author><name>Bin Xu</name></author><link href="http://arxiv.org/abs/2105.15033" rel="alternate"/><summary>Knowledge Graph has been proven effective in modeling structured information |
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580 and conceptual knowledge, especially in the medical domain. However, the lack |
|
|
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581 of high-quality annotated corpora remains a crucial problem for advancing the |
|
|
|
582 research and applications on this task. In order to accelerate the research for |
|
|
|
583 domain-specific knowledge graphs in the medical domain, we introduce DiaKG, a |
|
|
|
584 high-quality Chinese dataset for Diabetes knowledge graph, which contains |
|
|
|
585 22,050 entities and 6,890 relations in total. We implement recent typical |
|
|
|
586 methods for Named Entity Recognition and Relation Extraction as a benchmark to |
|
|
|
587 evaluate the proposed dataset thoroughly. Empirical results show that the DiaKG |
|
|
|
588 is challenging for most existing methods and further analysis is conducted to |
|
|
|
589 discuss future research direction for improvements. We hope the release of this |
|
|
|
590 dataset can assist the construction of diabetes knowledge graphs and facilitate |
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591 AI-based applications. |
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|
592 </summary></entry><entry><id>http://arxiv.org/abs/2105.11844</id><title>CI-dataset and DetDSCI methodology for detecting too small and too large critical infrastructures in satellite images: Airports and electrical substations as case study (update)</title><updated>2021-09-23T09:06:49.522772+00:00</updated><author><name>Francisco Pérez-Hernández</name></author><author><name>José Rodríguez-Ortega</name></author><author><name>Yassir Benhammou</name></author><author><name>Francisco Herrera</name></author><author><name>Siham Tabik</name></author><link href="http://arxiv.org/abs/2105.11844" rel="alternate"/><summary>The detection of critical infrastructures in large territories represented by |
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|
|
593 aerial and satellite images is of high importance in several fields such as in |
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|
|
594 security, anomaly detection, land use planning and land use change detection. |
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|
|
595 However, the detection of such infrastructures is complex as they have highly |
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|
596 variable shapes and sizes, i.e., some infrastructures, such as electrical |
|
|
|
597 substations, are too small while others, such as airports, are too large. |
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|
598 Besides, airports can have a surface area either small or too large with |
|
|
|
599 completely different shapes, which makes its correct detection challenging. As |
|
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|
600 far as we know, these limitations have not been tackled yet in previous works. |
|
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|
601 This paper presents (1) a smart Critical Infrastructure dataset, named |
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602 CI-dataset, organised into two scales, small and large scales critical |
|
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|
603 infrastructures and (2) a two-level resolution-independent critical |
|
|
|
604 infrastructure detection (DetDSCI) methodology that first determines the |
|
|
|
605 spatial resolution of the input image using a classification model, then |
|
|
|
606 analyses the image using the appropriate detector for that spatial resolution. |
|
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|
607 The present study targets two representative classes, airports and electrical |
|
|
|
608 substations. Our experiments show that DetDSCI methodology achieves up to |
|
|
|
609 37,53% F1 improvement with respect to Faster R-CNN, one of the most influential |
|
|
|
610 detection models. |
|
|
|
611 </summary></entry><entry><id>http://arxiv.org/abs/2103.13460</id><title>Under Pressure: Learning to Detect Slip with Barometric Tactile Sensors (update)</title><updated>2021-09-23T09:06:49.522356+00:00</updated><author><name>Abhinav Grover</name></author><author><name>Christopher Grebe</name></author><author><name>Philippe Nadeau</name></author><author><name>Jonathan Kelly</name></author><link href="http://arxiv.org/abs/2103.13460" rel="alternate"/><summary>Despite the utility of tactile information, tactile sensors have yet to be |
|
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|
612 widely deployed in industrial robotics settings. Part of the challenge lies in |
|
|
|
613 identifying slip and other key events from the tactile data stream. In this |
|
|
|
614 paper, we present a learning-based method to detect slip using barometric |
|
|
|
615 tactile sensors. Although these sensors have a low resolution, they have many |
|
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616 other desirable properties including high reliability and durability, a very |
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|
617 slim profile, and a low cost. We are able to achieve slip detection accuracies |
|
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|
618 of greater than 91% while being robust to the speed and direction of the slip |
|
|
|
619 motion. Further, we test our detector on two robot manipulation tasks involving |
|
|
|
620 common household objects and demonstrate successful generalization to |
|
|
|
621 real-world scenarios not seen during training. We show that barometric tactile |
|
|
|
622 sensing technology, combined with data-driven learning, is potentially suitable |
|
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|
623 for complex manipulation tasks such as slip compensation. |
|
|
|
624 </summary></entry><entry><id>http://arxiv.org/abs/2102.08633</id><title>Open-Retrieval Conversational Machine Reading (update)</title><updated>2021-09-23T09:06:49.521944+00:00</updated><author><name>Yifan Gao</name></author><author><name>Jingjing Li</name></author><author><name>Michael R. Lyu</name></author><author><name>Irwin King</name></author><link href="http://arxiv.org/abs/2102.08633" rel="alternate"/><summary>In conversational machine reading, systems need to interpret natural language |
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|
|
625 rules, answer high-level questions such as "May I qualify for VA health care |
|
|
|
626 benefits?", and ask follow-up clarification questions whose answer is necessary |
|
|
|
627 to answer the original question. However, existing works assume the rule text |
|
|
|
628 is provided for each user question, which neglects the essential retrieval step |
|
|
|
629 in real scenarios. In this work, we propose and investigate an open-retrieval |
|
|
|
630 setting of conversational machine reading. In the open-retrieval setting, the |
|
|
|
631 relevant rule texts are unknown so that a system needs to retrieve |
|
|
|
632 question-relevant evidence from a collection of rule texts, and answer users' |
|
|
|
633 high-level questions according to multiple retrieved rule texts in a |
|
|
|
634 conversational manner. We propose MUDERN, a Multi-passage Discourse-aware |
|
|
|
635 Entailment Reasoning Network which extracts conditions in the rule texts |
|
|
|
636 through discourse segmentation, conducts multi-passage entailment reasoning to |
|
|
|
637 answer user questions directly, or asks clarification follow-up questions to |
|
|
|
638 inquiry more information. On our created OR-ShARC dataset, MUDERN achieves the |
|
|
|
639 state-of-the-art performance, outperforming existing single-passage |
|
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|
640 conversational machine reading models as well as a new multi-passage |
|
|
|
641 conversational machine reading baseline by a large margin. In addition, we |
|
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642 conduct in-depth analyses to provide new insights into this new setting and our |
|
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643 model. |
|
|
|
644 </summary></entry><entry><id>http://arxiv.org/abs/2102.07358</id><title>Weak Adaptation Learning -- Addressing Cross-domain Data Insufficiency with Weak Annotator (update)</title><updated>2021-09-23T09:06:49.521525+00:00</updated><author><name>Shichao Xu</name></author><author><name>Lixu Wang</name></author><author><name>Yixuan Wang</name></author><author><name>Qi Zhu</name></author><link href="http://arxiv.org/abs/2102.07358" rel="alternate"/><summary>Data quantity and quality are crucial factors for data-driven learning |
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645 methods. In some target problem domains, there are not many data samples |
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646 available, which could significantly hinder the learning process. While data |
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647 from similar domains may be leveraged to help through domain adaptation, |
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648 obtaining high-quality labeled data for those source domains themselves could |
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649 be difficult or costly. To address such challenges on data insufficiency for |
|
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650 classification problem in a target domain, we propose a weak adaptation |
|
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651 learning (WAL) approach that leverages unlabeled data from a similar source |
|
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652 domain, a low-cost weak annotator that produces labels based on task-specific |
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653 heuristics, labeling rules, or other methods (albeit with inaccuracy), and a |
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654 small amount of labeled data in the target domain. Our approach first conducts |
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655 a theoretical analysis on the error bound of the trained classifier with |
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656 respect to the data quantity and the performance of the weak annotator, and |
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657 then introduces a multi-stage weak adaptation learning method to learn an |
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658 accurate classifier by lowering the error bound. Our experiments demonstrate |
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659 the effectiveness of our approach in learning an accurate classifier with |
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660 limited labeled data in the target domain and unlabeled data in the source |
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661 domain. |
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|
662 </summary></entry><entry><id>http://arxiv.org/abs/2102.04394</id><title>Learning with Density Matrices and Random Features (update)</title><updated>2021-09-23T09:06:49.521043+00:00</updated><author><name>Fabio A. González</name></author><author><name>Alejandro Gallego</name></author><author><name>Santiago Toledo-Cortés</name></author><author><name>Vladimir Vargas-Calderón</name></author><link href="http://arxiv.org/abs/2102.04394" rel="alternate"/><summary>A density matrix describes the statistical state of a quantum system. It is a |
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663 powerful formalism to represent both the quantum and classical uncertainty of |
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664 quantum systems and to express different statistical operations such as |
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665 measurement, system combination and expectations as linear algebra operations. |
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666 This paper explores how density matrices can be used as a building block to |
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|
667 build machine learning models exploiting their ability to straightforwardly |
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|
668 combine linear algebra and probability. One of the main results of the paper is |
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669 to show that density matrices coupled with random Fourier features could |
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670 approximate arbitrary probability distributions over $\mathbb{R}^n$. Based on |
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|
671 this finding the paper builds different models for density estimation, |
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672 classification and regression. These models are differentiable, so it is |
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673 possible to integrate them with other differentiable components, such as deep |
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|
674 learning architectures and to learn their parameters using gradient-based |
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675 optimization. In addition, the paper presents optimization-less training |
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676 strategies based on estimation and model averaging. The models are evaluated in |
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677 benchmark tasks and the results are reported and discussed. |
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|
678 </summary></entry><entry><id>http://arxiv.org/abs/2011.11152</id><title>Understanding and Scheduling Weight Decay (update)</title><updated>2021-09-23T09:06:49.520655+00:00</updated><author><name>Zeke Xie</name></author><author><name>Issei Sato</name></author><author><name>Masashi Sugiyama</name></author><link href="http://arxiv.org/abs/2011.11152" rel="alternate"/><summary>Weight decay is a popular and even necessary regularization technique for |
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679 training deep neural networks that generalize well. Previous work usually |
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680 interpreted weight decay as a Gaussian prior from the Bayesian perspective. |
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681 However, weight decay sometimes shows mysterious behaviors beyond the |
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682 conventional understanding. For example, the optimal weight decay value tends |
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683 to be zero given long enough training time. Moreover, existing work typically |
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|
684 failed to recognize the importance of scheduling weight decay during training. |
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685 Our work aims at theoretically understanding novel behaviors of weight decay |
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|
686 and designing schedulers for weight decay in deep learning. This paper mainly |
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|
687 has three contributions. First, we propose a novel theoretical interpretation |
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|
688 of weight decay from the perspective of learning dynamics. Second, we propose a |
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689 novel weight-decay linear scaling rule for large-batch training that |
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|
690 proportionally increases weight decay rather than the learning rate as the |
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691 batch size increases. Third, we provide an effective learning-rate-aware |
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692 scheduler for weight decay, called the Stable Weight Decay (SWD) method, which, |
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|
693 to the best of our knowledge, is the first practical design for weight decay |
|
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694 scheduling. In our various experiments, the SWD method often makes improvements |
|
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|
695 over $L_{2}$ Regularization and Decoupled Weight Decay. |
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|
696 </summary></entry><entry><id>http://arxiv.org/abs/2011.02073</id><title>MBB: Model-Based Baseline for Efficient Reinforcement Learning (update)</title><updated>2021-09-23T09:06:49.520212+00:00</updated><author><name>Xubo Lyu</name></author><author><name>Site Li</name></author><author><name>Seth Siriya</name></author><author><name>Ye Pu</name></author><author><name>Mo Chen</name></author><link href="http://arxiv.org/abs/2011.02073" rel="alternate"/><summary>Model-free reinforcement learning (RL) is capable of learning control |
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697 policies for high-dimensional, complex robotic tasks, but tends to be |
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698 data-inefficient. Model-based RL tends to be more data-efficient but often |
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699 suffers from learning a high-dimensional model that is good enough for policy |
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700 improvement. This limits its use to learning simple models for restrictive |
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701 domains. Optimal control generates solutions without collecting any data, |
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702 assuming an accurate model of the system and environment is known, which is |
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703 often true in many control theory applications. However, optimal control cannot |
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|
704 be scaled to problems with a high-dimensional state space. In this paper, we |
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|
705 propose a novel approach to alleviate data inefficiency of model-free RL in |
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706 high-dimensional problems by warm-starting the learning process using a |
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707 lower-dimensional model-based solution. Particularly, we initialize a baseline |
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|
708 function for the high-dimensional RL problem via supervision from a |
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|
709 lower-dimensional value function, which can be obtained by solving a |
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710 lower-dimensional problem with a known, approximate model using "classical" |
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|
711 techniques such as value iteration or optimal control. Therefore, our approach |
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|
712 implicitly exploits the model priors from simplified problem space to |
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|
713 facilitate the policy learning in high-dimensional RL tasks. We demonstrate our |
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|
714 approach on two representative robotic learning tasks and observe significant |
|
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|
715 improvement in policy performance and learning efficiency. We also evaluate our |
|
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|
716 method empirically with a third task. |
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|
717 </summary></entry><entry><id>http://arxiv.org/abs/2004.12908</id><title>Omnidirectional Transfer for Quasilinear Lifelong Learning (update)</title><updated>2021-09-23T09:06:49.519512+00:00</updated><author><name>Joshua T. Vogelstein</name></author><author><name>Jayanta Dey</name></author><author><name>Hayden S. Helm</name></author><author><name>Will LeVine</name></author><author><name>Ronak D. Mehta</name></author><author><name>Ali Geisa</name></author><author><name>Haoyin Xu</name></author><author><name>Gido M. van de Ven</name></author><author><name>Emily Chang</name></author><author><name>Chenyu Gao</name></author><author><name>Weiwei Yang</name></author><author><name>Bryan Tower</name></author><author><name>Jonathan Larson</name></author><author><name>Christopher M. White</name></author><author><name>Carey E. Priebe</name></author><link href="http://arxiv.org/abs/2004.12908" rel="alternate"/><summary>In biological learning, data are used to improve performance not only on the |
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718 current task, but also on previously encountered and as yet unencountered |
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|
719 tasks. In contrast, classical machine learning starts from a blank slate, or |
|
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|
720 tabula rasa, using data only for the single task at hand. While typical |
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|
721 transfer learning algorithms can improve performance on future tasks, their |
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|
722 performance on prior tasks degrades upon learning new tasks (called |
|
|
|
723 catastrophic forgetting). Many recent approaches for continual or lifelong |
|
|
|
724 learning have attempted to maintain performance given new tasks. But striving |
|
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|
725 to avoid forgetting sets the goal unnecessarily low: the goal of lifelong |
|
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|
726 learning, whether biological or artificial, should be to improve performance on |
|
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|
727 all tasks (including past and future) with any new data. We propose |
|
|
|
728 omnidirectional transfer learning algorithms, which includes two special cases |
|
|
|
729 of interest: decision forests and deep networks. Our key insight is the |
|
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|
730 development of the omni-voter layer, which ensembles representations learned |
|
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|
731 independently on all tasks to jointly decide how to proceed on any given new |
|
|
|
732 data point, thereby improving performance on both past and future tasks. Our |
|
|
|
733 algorithms demonstrate omnidirectional transfer in a variety of simulated and |
|
|
|
734 real data scenarios, including tabular data, image data, spoken data, and |
|
|
|
735 adversarial tasks. Moreover, they do so with quasilinear space and time |
|
|
|
736 complexity. |
|
|
|
737 </summary></entry><entry><id>http://arxiv.org/abs/2109.10322</id><title>CondNet: Conditional Classifier for Scene Segmentation</title><updated>2021-09-23T09:06:49.519051+00:00</updated><author><name>Changqian Yu</name></author><author><name>Yuanjie Shao</name></author><author><name>Changxin Gao</name></author><author><name>Nong Sang</name></author><link href="http://arxiv.org/abs/2109.10322" rel="alternate"/><summary>The fully convolutional network (FCN) has achieved tremendous success in |
|
|
|
738 dense visual recognition tasks, such as scene segmentation. The last layer of |
|
|
|
739 FCN is typically a global classifier (1x1 convolution) to recognize each pixel |
|
|
|
740 to a semantic label. We empirically show that this global classifier, ignoring |
|
|
|
741 the intra-class distinction, may lead to sub-optimal results. |
|
|
|
742 </summary></entry><entry><id>http://arxiv.org/abs/2109.10317</id><title>Introduction to Neural Network Verification</title><updated>2021-09-23T09:06:49.518738+00:00</updated><author><name>Aws Albarghouthi</name></author><link href="http://arxiv.org/abs/2109.10317" rel="alternate"/><summary>Deep learning has transformed the way we think of software and what it can |
|
|
|
743 do. But deep neural networks are fragile and their behaviors are often |
|
|
|
744 surprising. In many settings, we need to provide formal guarantees on the |
|
|
|
745 safety, security, correctness, or robustness of neural networks. This book |
|
|
|
746 covers foundational ideas from formal verification and their adaptation to |
|
|
|
747 reasoning about neural networks and deep learning. |
|
|
|
748 </summary></entry><entry><id>http://arxiv.org/abs/2109.10312</id><title>Example-Driven Model-Based Reinforcement Learning for Solving Long-Horizon Visuomotor Tasks</title><updated>2021-09-23T09:06:49.518267+00:00</updated><author><name>Bohan Wu</name></author><author><name>Suraj Nair</name></author><author><name>Li Fei-Fei</name></author><author><name>Chelsea Finn</name></author><link href="http://arxiv.org/abs/2109.10312" rel="alternate"/><summary>In this paper, we study the problem of learning a repertoire of low-level |
|
|
|
749 skills from raw images that can be sequenced to complete long-horizon |
|
|
|
750 visuomotor tasks. Reinforcement learning (RL) is a promising approach for |
|
|
|
751 acquiring short-horizon skills autonomously. However, the focus of RL |
|
|
|
752 algorithms has largely been on the success of those individual skills, more so |
|
|
|
753 than learning and grounding a large repertoire of skills that can be sequenced |
|
|
|
754 to complete extended multi-stage tasks. The latter demands robustness and |
|
|
|
755 persistence, as errors in skills can compound over time, and may require the |
|
|
|
756 robot to have a number of primitive skills in its repertoire, rather than just |
|
|
|
757 one. To this end, we introduce EMBR, a model-based RL method for learning |
|
|
|
758 primitive skills that are suitable for completing long-horizon visuomotor |
|
|
|
759 tasks. EMBR learns and plans using a learned model, critic, and success |
|
|
|
760 classifier, where the success classifier serves both as a reward function for |
|
|
|
761 RL and as a grounding mechanism to continuously detect if the robot should |
|
|
|
762 retry a skill when unsuccessful or under perturbations. Further, the learned |
|
|
|
763 model is task-agnostic and trained using data from all skills, enabling the |
|
|
|
764 robot to efficiently learn a number of distinct primitives. These visuomotor |
|
|
|
765 primitive skills and their associated pre- and post-conditions can then be |
|
|
|
766 directly combined with off-the-shelf symbolic planners to complete long-horizon |
|
|
|
767 tasks. On a Franka Emika robot arm, we find that EMBR enables the robot to |
|
|
|
768 complete three long-horizon visuomotor tasks at 85% success rate, such as |
|
|
|
769 organizing an office desk, a file cabinet, and drawers, which require |
|
|
|
770 sequencing up to 12 skills, involve 14 unique learned primitives, and demand |
|
|
|
771 generalization to novel objects. |
|
|
|
772 </summary></entry><entry><id>http://arxiv.org/abs/2109.10303</id><title>Computing Complexity-aware Plans Using Kolmogorov Complexity</title><updated>2021-09-23T09:06:49.517919+00:00</updated><author><name>Elis Stefansson</name></author><author><name>Karl H. Johansson</name></author><link href="http://arxiv.org/abs/2109.10303" rel="alternate"/><summary>In this paper, we introduce complexity-aware planning for finite-horizon |
|
|
|
773 deterministic finite automata with rewards as outputs, based on Kolmogorov |
|
|
|
774 complexity. Kolmogorov complexity is considered since it can detect |
|
|
|
775 computational regularities of deterministic optimal policies. We present a |
|
|
|
776 planning objective yielding an explicit trade-off between a policy's |
|
|
|
777 performance and complexity. It is proven that maximising this objective is |
|
|
|
778 non-trivial in the sense that dynamic programming is infeasible. We present two |
|
|
|
779 algorithms obtaining low-complexity policies, where the first algorithm obtains |
|
|
|
780 a low-complexity optimal policy, and the second algorithm finds a policy |
|
|
|
781 maximising performance while maintaining local (stage-wise) complexity |
|
|
|
782 constraints. We evaluate the algorithms on a simple navigation task for a |
|
|
|
783 mobile robot, where our algorithms yield low-complexity policies that concur |
|
|
|
784 with intuition. |
|
|
|
785 </summary></entry><entry><id>http://arxiv.org/abs/2109.10285</id><title>Early and Revocable Time Series Classification</title><updated>2021-09-23T09:06:49.517510+00:00</updated><author><name>Youssef Achenchabe</name></author><author><name>Alexis Bondu</name></author><author><name>Antoine Cornuéjols</name></author><author><name>Vincent Lemaire</name></author><link href="http://arxiv.org/abs/2109.10285" rel="alternate"/><summary>Many approaches have been proposed for early classification of time series in |
|
|
|
786 light of itssignificance in a wide range of applications including healthcare, |
|
|
|
787 transportation and fi-nance. Until now, the early classification problem has |
|
|
|
788 been dealt with by considering onlyirrevocable decisions. This paper introduces |
|
|
|
789 a new problem calledearly and revocabletimeseries classification, where the |
|
|
|
790 decision maker can revoke its earlier decisions based on thenew available |
|
|
|
791 measurements. In order to formalize and tackle this problem, we propose anew |
|
|
|
792 cost-based framework and derive two new approaches from it. The first approach |
|
|
|
793 doesnot consider explicitly the cost of changing decision, while the second one |
|
|
|
794 does. Exten-sive experiments are conducted to evaluate these approaches on a |
|
|
|
795 large benchmark of realdatasets. The empirical results obtained convincingly |
|
|
|
796 show (i) that the ability of revok-ing decisions significantly improves |
|
|
|
797 performance over the irrevocable regime, and (ii) thattaking into account the |
|
|
|
798 cost of changing decision brings even better results in |
|
|
|
799 general.Keywords:revocable decisions, cost estimation, online decision making |
|
|
|
800 </summary></entry><entry><id>http://arxiv.org/abs/2109.10246</id><title>Does Vision-and-Language Pretraining Improve Lexical Grounding?</title><updated>2021-09-23T09:06:49.517131+00:00</updated><author><name>Tian Yun</name></author><author><name>Chen Sun</name></author><author><name>Ellie Pavlick</name></author><link href="http://arxiv.org/abs/2109.10246" rel="alternate"/><summary>Linguistic representations derived from text alone have been criticized for |
|
|
|
801 their lack of grounding, i.e., connecting words to their meanings in the |
|
|
|
802 physical world. Vision-and-Language (VL) models, trained jointly on text and |
|
|
|
803 image or video data, have been offered as a response to such criticisms. |
|
|
|
804 However, while VL pretraining has shown success on multimodal tasks such as |
|
|
|
805 visual question answering, it is not yet known how the internal linguistic |
|
|
|
806 representations themselves compare to their text-only counterparts. This paper |
|
|
|
807 compares the semantic representations learned via VL vs. text-only pretraining |
|
|
|
808 for two recent VL models using a suite of analyses (clustering, probing, and |
|
|
|
809 performance on a commonsense question answering task) in a language-only |
|
|
|
810 setting. We find that the multimodal models fail to significantly outperform |
|
|
|
811 the text-only variants, suggesting that future work is required if multimodal |
|
|
|
812 pretraining is to be pursued as a means of improving NLP in general. |
|
|
|
813 </summary></entry><entry><id>http://arxiv.org/abs/2109.10231</id><title>SalienTrack: providing salient information for semi-automated self-tracking feedback with model explanations</title><updated>2021-09-23T09:06:49.516665+00:00</updated><author><name>Yunlong Wang</name></author><author><name>Jiaying Liu</name></author><author><name>Homin Park</name></author><author><name>Jordan Schultz-McArdle</name></author><author><name>Stephanie Rosenthal</name></author><author><name>Brian Y Lim</name></author><link href="http://arxiv.org/abs/2109.10231" rel="alternate"/><summary>Self-tracking can improve people's awareness of their unhealthy behaviors to |
|
|
|
814 provide insights towards behavior change. Prior work has explored how |
|
|
|
815 self-trackers reflect on their logged data, but it remains unclear how much |
|
|
|
816 they learn from the tracking feedback, and which information is more useful. |
|
|
|
817 Indeed, the feedback can still be overwhelming, and making it concise can |
|
|
|
818 improve learning by increasing focus and reducing interpretation burden. We |
|
|
|
819 conducted a field study of mobile food logging with two feedback modes (manual |
|
|
|
820 journaling and automatic annotation of food images) and identified learning |
|
|
|
821 differences regarding nutrition, assessment, behavioral, and contextual |
|
|
|
822 information. We propose a Self-Tracking Feedback Saliency Framework to define |
|
|
|
823 when to provide feedback, on which specific information, why those details, and |
|
|
|
824 how to present them (as manual inquiry or automatic feedback). We propose |
|
|
|
825 SalienTrack to implement these requirements. Using the data collected from the |
|
|
|
826 user study, we trained a machine learning model to predict whether a user would |
|
|
|
827 learn from each tracked event. Using explainable AI (XAI) techniques, we |
|
|
|
828 identified the most salient features per instance and why they lead to positive |
|
|
|
829 learning outcomes. We discuss implications for learnability in self-tracking, |
|
|
|
830 and how adding model explainability expands opportunities for improving |
|
|
|
831 feedback experience. |
|
|
|
832 </summary></entry><entry><id>http://arxiv.org/abs/2109.10217</id><title>Shape Inference and Grammar Induction for Example-based Procedural Generation</title><updated>2021-09-23T09:06:49.516292+00:00</updated><author><name>Gillis Hermans</name></author><author><name>Thomas Winters</name></author><author><name>Luc De Raedt</name></author><link href="http://arxiv.org/abs/2109.10217" rel="alternate"/><summary>Designers increasingly rely on procedural generation for automatic generation |
|
|
|
833 of content in various industries. These techniques require extensive knowledge |
|
|
|
834 of the desired content, and about how to actually implement such procedural |
|
|
|
835 methods. Algorithms for learning interpretable generative models from example |
|
|
|
836 content could alleviate both difficulties. We propose SIGI, a novel method for |
|
|
|
837 inferring shapes and inducing a shape grammar from grid-based 3D building |
|
|
|
838 examples. This interpretable grammar is well-suited for co-creative design. |
|
|
|
839 Applied to Minecraft buildings, we show how the shape grammar can be used to |
|
|
|
840 automatically generate new buildings in a similar style. |
|
|
|
841 </summary></entry><entry><id>http://arxiv.org/abs/2109.10200</id><title>Off-line approximate dynamic programming for the vehicle routing problem with stochastic customers and demands via decentralized decision-making</title><updated>2021-09-23T09:06:49.515928+00:00</updated><author><name>Mohsen Dastpak</name></author><author><name>Fausto Errico</name></author><link href="http://arxiv.org/abs/2109.10200" rel="alternate"/><summary>This paper studies a stochastic variant of the vehicle routing problem (VRP) |
|
|
|
842 where both customer locations and demands are uncertain. In particular, |
|
|
|
843 potential customers are not restricted to a predefined customer set but are |
|
|
|
844 continuously spatially distributed in a given service area. The objective is to |
|
|
|
845 maximize the served demands while fulfilling vehicle capacities and time |
|
|
|
846 restrictions. We call this problem the VRP with stochastic customers and |
|
|
|
847 demands (VRPSCD). For this problem, we first propose a Markov Decision Process |
|
|
|
848 (MDP) formulation representing the classical centralized decision-making |
|
|
|
849 perspective where one decision-maker establishes the routes of all vehicles. |
|
|
|
850 While the resulting formulation turns out to be intractable, it provides us |
|
|
|
851 with the ground to develop a new MDP formulation of the VRPSCD representing a |
|
|
|
852 decentralized decision-making framework, where vehicles autonomously establish |
|
|
|
853 their own routes. This new formulation allows us to develop several strategies |
|
|
|
854 to reduce the dimension of the state and action spaces, resulting in a |
|
|
|
855 considerably more tractable problem. We solve the decentralized problem via |
|
|
|
856 Reinforcement Learning, and in particular, we develop a Q-learning algorithm |
|
|
|
857 featuring state-of-the-art acceleration techniques such as Replay Memory and |
|
|
|
858 Double Q Network. Computational results show that our method considerably |
|
|
|
859 outperforms two commonly adopted benchmark policies (random and heuristic). |
|
|
|
860 Moreover, when comparing with existing literature, we show that our approach |
|
|
|
861 can compete with specialized methods developed for the particular case of the |
|
|
|
862 VRPSCD where customer locations and expected demands are known in advance. |
|
|
|
863 Finally, we show that the value functions and policies obtained by our |
|
|
|
864 algorithm can be easily embedded in Rollout algorithms, thus further improving |
|
|
|
865 their performances. |
|
|
|
866 </summary></entry><entry><id>http://arxiv.org/abs/2109.10199</id><title>Design and implementation of a parsimonious neuromorphic PID for onboard altitude control for MAVs using neuromorphic processors</title><updated>2021-09-23T09:06:49.515541+00:00</updated><author><name>Stein Stroobants</name></author><author><name>Julien Dupeyroux</name></author><author><name>Guido de Croon</name></author><link href="http://arxiv.org/abs/2109.10199" rel="alternate"/><summary>The great promises of neuromorphic sensing and processing for robotics have |
|
|
|
867 led researchers and engineers to investigate novel models for robust and |
|
|
|
868 reliable control of autonomous robots (navigation, obstacle detection and |
|
|
|
869 avoidance, etc.), especially for quadrotors in challenging contexts such as |
|
|
|
870 drone racing and aggressive maneuvers. Using spiking neural networks, these |
|
|
|
871 models can be run on neuromorphic hardware to benefit from outstanding update |
|
|
|
872 rates and high energy efficiency. Yet, low-level controllers are often |
|
|
|
873 neglected and remain outside of the neuromorphic loop. Designing low-level |
|
|
|
874 neuromorphic controllers is crucial to remove the standard PID, and therefore |
|
|
|
875 benefit from all the advantages of closing the neuromorphic loop. In this |
|
|
|
876 paper, we propose a parsimonious and adjustable neuromorphic PID controller, |
|
|
|
877 endowed with a minimal number of 93 neurons sparsely connected to achieve |
|
|
|
878 autonomous, onboard altitude control of a quadrotor equipped with Intel's Loihi |
|
|
|
879 neuromorphic chip. We successfully demonstrate the robustness of our proposed |
|
|
|
880 network in a set of experiments where the quadrotor is requested to reach a |
|
|
|
881 target altitude from take-off. Our results confirm the suitability of such |
|
|
|
882 low-level neuromorphic controllers, ultimately with a very high update |
|
|
|
883 frequency. |
|
|
|
884 </summary></entry><entry><id>http://arxiv.org/abs/2109.10187</id><title>Oriented Object Detection in Aerial Images Based on Area Ratio of Parallelogram</title><updated>2021-09-23T09:06:49.515064+00:00</updated><author><name>Xinyu Yu</name></author><author><name>Mi Lin</name></author><author><name>Jiangping Lu</name></author><author><name>Linlin Ou</name></author><link href="http://arxiv.org/abs/2109.10187" rel="alternate"/><summary>Rotated object detection is a challenging task in aerial images as the object |
|
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|
885 in aerial images are displayed in arbitrary directions and usually densely |
|
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|
886 packed. Although considerable progress has been made, there are still |
|
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|
887 challenges that existing regression-based rotation detectors suffer the problem |
|
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888 of discontinuous boundaries, which is directly caused by angular periodicity or |
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889 corner ordering. In this paper, we propose a simple effective framework to |
|
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|
890 address the above challenges. Instead of directly regressing the five |
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|
891 parameters (coordinates of the central point, width, height, and rotation |
|
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|
892 angle) or the four vertices, we use the area ratio of parallelogram (ARP) to |
|
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|
893 accurately describe a multi-oriented object. Specifically, we regress |
|
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|
894 coordinates of center point, height and width of minimum circumscribed |
|
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|
895 rectangle of oriented object and three area ratios {\lambda}_1, {\lambda}_2 and |
|
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|
896 {\lambda}_3. This may facilitate the offset learning and avoid the issue of |
|
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|
897 angular periodicity or label points sequence for oriented objects. To further |
|
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|
898 remedy the confusion issue nearly horizontal objects, we employ the area ratio |
|
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|
899 between the object and its horizontal bounding box (minimum circumscribed |
|
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|
900 rectangle) to guide the selection of horizontal or oriented detection for each |
|
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|
901 object. We also propose a rotation efficient IoU loss (R-EIoU) to connect the |
|
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|
902 horizontal bounding box with the three area ratios and improve the accurate for |
|
|
|
903 the rotating bounding box. Experimental results on three remote sensing |
|
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|
904 datasets including HRSC2016, DOTA and UCAS-AOD and scene text including |
|
|
|
905 ICDAR2015 show that our method achieves superior detection performance compared |
|
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|
906 with many state-of-the-art approaches. The code and model will be coming with |
|
|
|
907 paper published. |
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|
908 </summary></entry><entry><id>http://arxiv.org/abs/2109.10173</id><title>Long-Term Exploration in Persistent MDPs</title><updated>2021-09-23T09:06:49.514674+00:00</updated><author><name>Leonid Ugadiarov</name></author><author><name>Alexey Skrynnik</name></author><author><name>Aleksandr I. Panov</name></author><link href="http://arxiv.org/abs/2109.10173" rel="alternate"/><summary>Exploration is an essential part of reinforcement learning, which restricts |
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909 the quality of learned policy. Hard-exploration environments are defined by |
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|
910 huge state space and sparse rewards. In such conditions, an exhaustive |
|
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|
911 exploration of the environment is often impossible, and the successful training |
|
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|
912 of an agent requires a lot of interaction steps. In this paper, we propose an |
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|
913 exploration method called Rollback-Explore (RbExplore), which utilizes the |
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|
914 concept of the persistent Markov decision process, in which agents during |
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|
915 training can roll back to visited states. We test our algorithm in the |
|
|
|
916 hard-exploration Prince of Persia game, without rewards and domain knowledge. |
|
|
|
917 At all used levels of the game, our agent outperforms or shows comparable |
|
|
|
918 results with state-of-the-art curiosity methods with knowledge-based intrinsic |
|
|
|
919 motivation: ICM and RND. An implementation of RbExplore can be found at |
|
|
|
920 https://github.com/cds-mipt/RbExplore. |
|
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|
921 </summary></entry><entry><id>http://arxiv.org/abs/2109.10149</id><title>Interpretable Directed Diversity: Leveraging Model Explanations for Iterative Crowd Ideation</title><updated>2021-09-23T09:06:49.514210+00:00</updated><author><name>Yunlong Wang</name></author><author><name>Priyadarshini Venkatesh</name></author><author><name>Brian Y. Lim</name></author><link href="http://arxiv.org/abs/2109.10149" rel="alternate"/><summary>Feedback can help crowdworkers to improve their ideations. However, current |
|
|
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922 feedback methods require human assessment from facilitators or peers. This is |
|
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|
923 not scalable to large crowds. We propose Interpretable Directed Diversity to |
|
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|
924 automatically predict ideation quality and diversity scores, and provide AI |
|
|
|
925 explanations - Attribution, Contrastive Attribution, and Counterfactual |
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|
926 Suggestions - for deeper feedback on why ideations were scored (low), and how |
|
|
|
927 to get higher scores. These explanations provide multi-faceted feedback as |
|
|
|
928 users iteratively improve their ideation. We conducted think aloud and |
|
|
|
929 controlled user studies to understand how various explanations are used, and |
|
|
|
930 evaluated whether explanations improve ideation diversity and quality. Users |
|
|
|
931 appreciated that explanation feedback helped focus their efforts and provided |
|
|
|
932 directions for improvement. This resulted in explanations improving diversity |
|
|
|
933 compared to no feedback or feedback with predictions only. Hence, our approach |
|
|
|
934 opens opportunities for explainable AI towards scalable and rich feedback for |
|
|
|
935 iterative crowd ideation. |
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|
|
936 </summary></entry><entry><id>http://arxiv.org/abs/2109.10129</id><title>Learning General Optimal Policies with Graph Neural Networks: Expressive Power, Transparency, and Limits</title><updated>2021-09-23T09:06:49.513806+00:00</updated><author><name>Simon Ståhlberg</name></author><author><name>Blai Bonet</name></author><author><name>Hector Geffner</name></author><link href="http://arxiv.org/abs/2109.10129" rel="alternate"/><summary>It has been recently shown that general policies for many classical planning |
|
|
|
937 domains can be expressed and learned in terms of a pool of features defined |
|
|
|
938 from the domain predicates using a description logic grammar. At the same time, |
|
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|
939 most description logics correspond to a fragment of $k$-variable counting logic |
|
|
|
940 ($C_k$) for $k=2$, that has been shown to provide a tight characterization of |
|
|
|
941 the expressive power of graph neural networks. In this work, we make use of |
|
|
|
942 these results to understand the power and limits of using graph neural networks |
|
|
|
943 (GNNs) for learning optimal general policies over a number of tractable |
|
|
|
944 planning domains where such policies are known to exist. For this, we train a |
|
|
|
945 simple GNN in a supervised manner to approximate the optimal value function |
|
|
|
946 $V^{*}(s)$ of a number of sample states $s$. As predicted by the theory, it is |
|
|
|
947 observed that general optimal policies are obtained in domains where general |
|
|
|
948 optimal value functions can be defined with $C_2$ features but not in those |
|
|
|
949 requiring more expressive $C_3$ features. In addition, it is observed that the |
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|
950 features learned are in close correspondence with the features needed to |
|
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|
951 express $V^{*}$ in closed form. The theory and the analysis of the domains let |
|
|
|
952 us understand the features that are actually learned as well as those that |
|
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|
953 cannot be learned in this way, and let us move in a principled manner from a |
|
|
|
954 combinatorial optimization approach to learning general policies to a |
|
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|
955 potentially, more robust and scalable approach based on deep learning. |
|
|
|
956 </summary></entry><entry><id>http://arxiv.org/abs/2109.10106</id><title>Distributed Mission Planning of Complex Tasks for Heterogeneous Multi-Robot Teams</title><updated>2021-09-23T09:06:49.513430+00:00</updated><author><name>Barbara Arbanas Ferreira</name></author><author><name>Tamara Petrović</name></author><author><name>Stjepan Bogdan</name></author><link href="http://arxiv.org/abs/2109.10106" rel="alternate"/><summary>In this paper, we propose a distributed multi-stage optimization method for |
|
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957 planning complex missions for heterogeneous multi-robot teams. This class of |
|
|
|
958 problems involves tasks that can be executed in different ways and are |
|
|
|
959 associated with cross-schedule dependencies that constrain the schedules of the |
|
|
|
960 different robots in the system. The proposed approach involves a |
|
|
|
961 multi-objective heuristic search of the mission, represented as a hierarchical |
|
|
|
962 tree that defines the mission goal. This procedure outputs several favorable |
|
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|
963 ways to fulfill the mission, which directly feed into the next stage of the |
|
|
|
964 method. We propose a distributed metaheuristic based on evolutionary |
|
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|
965 computation to allocate tasks and generate schedules for the set of chosen |
|
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|
966 decompositions. The method is evaluated in a simulation setup of an automated |
|
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|
967 greenhouse use case, where we demonstrate the method's ability to adapt the |
|
|
|
968 planning strategy depending on the available robots and the given optimization |
|
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|
969 criteria. |
|
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|
970 </summary></entry><entry><id>http://arxiv.org/abs/2109.10100</id><title>A Novel Structured Natural Gradient Descent for Deep Learning</title><updated>2021-09-23T09:06:49.513082+00:00</updated><author><name>Weihua Liu</name></author><author><name>Xiabi Liu</name></author><link href="http://arxiv.org/abs/2109.10100" rel="alternate"/><summary>Natural gradient descent (NGD) provided deep insights and powerful tools to |
|
|
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971 deep neural networks. However the computation of Fisher information matrix |
|
|
|
972 becomes more and more difficult as the network structure turns large and |
|
|
|
973 complex. This paper proposes a new optimization method whose main idea is to |
|
|
|
974 accurately replace the natural gradient optimization by reconstructing the |
|
|
|
975 network. More specifically, we reconstruct the structure of the deep neural |
|
|
|
976 network, and optimize the new network using traditional gradient descent (GD). |
|
|
|
977 The reconstructed network achieves the effect of the optimization way with |
|
|
|
978 natural gradient descent. Experimental results show that our optimization |
|
|
|
979 method can accelerate the convergence of deep network models and achieve better |
|
|
|
980 performance than GD while sharing its computational simplicity. |
|
|
|
981 </summary></entry><entry><id>http://arxiv.org/abs/2109.10086</id><title>SPLADE v2: Sparse Lexical and Expansion Model for Information Retrieval</title><updated>2021-09-23T09:06:49.512667+00:00</updated><author><name>Thibault Formal</name></author><author><name>Carlos Lassance</name></author><author><name>Benjamin Piwowarski</name></author><author><name>Stéphane Clinchant</name></author><link href="http://arxiv.org/abs/2109.10086" rel="alternate"/><summary>In neural Information Retrieval (IR), ongoing research is directed towards |
|
|
|
982 improving the first retriever in ranking pipelines. Learning dense embeddings |
|
|
|
983 to conduct retrieval using efficient approximate nearest neighbors methods has |
|
|
|
984 proven to work well. Meanwhile, there has been a growing interest in learning |
|
|
|
985 \emph{sparse} representations for documents and queries, that could inherit |
|
|
|
986 from the desirable properties of bag-of-words models such as the exact matching |
|
|
|
987 of terms and the efficiency of inverted indexes. Introduced recently, the |
|
|
|
988 SPLADE model provides highly sparse representations and competitive results |
|
|
|
989 with respect to state-of-the-art dense and sparse approaches. In this paper, we |
|
|
|
990 build on SPLADE and propose several significant improvements in terms of |
|
|
|
991 effectiveness and/or efficiency. More specifically, we modify the pooling |
|
|
|
992 mechanism, benchmark a model solely based on document expansion, and introduce |
|
|
|
993 models trained with distillation. We also report results on the BEIR benchmark. |
|
|
|
994 Overall, SPLADE is considerably improved with more than $9$\% gains on NDCG@10 |
|
|
|
995 on TREC DL 2019, leading to state-of-the-art results on the BEIR benchmark. |
|
|
|
996 </summary></entry><entry><id>http://arxiv.org/abs/2109.10085</id><title>Heterogeneous Ensemble for ESG Ratings Prediction</title><updated>2021-09-23T09:06:49.512201+00:00</updated><author><name>Tim Krappel</name></author><author><name>Alex Bogun</name></author><author><name>Damian Borth</name></author><link href="http://arxiv.org/abs/2109.10085" rel="alternate"/><summary>Over the past years, topics ranging from climate change to human rights have |
|
|
|
997 seen increasing importance for investment decisions. Hence, investors (asset |
|
|
|
998 managers and asset owners) who wanted to incorporate these issues started to |
|
|
|
999 assess companies based on how they handle such topics. For this assessment, |
|
|
|
1000 investors rely on specialized rating agencies that issue ratings along the |
|
|
|
1001 environmental, social and governance (ESG) dimensions. Such ratings allow them |
|
|
|
1002 to make investment decisions in favor of sustainability. However, rating |
|
|
|
1003 agencies base their analysis on subjective assessment of sustainability |
|
|
|
1004 reports, not provided by every company. Furthermore, due to human labor |
|
|
|
1005 involved, rating agencies are currently facing the challenge to scale up the |
|
|
|
1006 coverage in a timely manner. |
|
|
|
1007 </summary></entry><entry><id>http://arxiv.org/abs/2109.10065</id><title>Comparison of Neural Network based Soft Computing Techniques for Electromagnetic Modeling of a Microstrip Patch Antenna</title><updated>2021-09-23T09:06:49.511839+00:00</updated><author><name>Yuvraj Singh Malhi</name></author><author><name>Navneet Gupta</name></author><link href="http://arxiv.org/abs/2109.10065" rel="alternate"/><summary>This paper presents the comparison of various neural networks and algorithms |
|
|
|
1008 based on accuracy, quickness, and consistency for antenna modelling. Using |
|
|
|
1009 Nntool by MATLAB, 22 different combinations of networks and training algorithms |
|
|
|
1010 are used to predict the dimensions of a rectangular microstrip antenna using |
|
|
|
1011 dielectric constant, height of substrate, and frequency of operation as input. |
|
|
|
1012 Comparison and characterization of networks is done based on accuracy, mean |
|
|
|
1013 square error, and training time. Algorithms, on the other hand, are analyzed by |
|
|
|
1014 their accuracy, speed, reliability, and smoothness in the training process. |
|
|
|
1015 Finally, these results are analyzed, and recommendations are made for each |
|
|
|
1016 neural network and algorithm based on uses, advantages, and disadvantages. For |
|
|
|
1017 example, it is observed that Reduced Radial Bias network is the most accurate |
|
|
|
1018 network and Scaled Conjugate Gradient is the most reliable algorithm for |
|
|
|
1019 electromagnetic modelling. This paper will help a researcher find the optimum |
|
|
|
1020 network and algorithm directly without doing time-taking experimentation. |
|
|
|
1021 </summary></entry><entry><id>http://arxiv.org/abs/2109.10057</id><title>LOTR: Face Landmark Localization Using Localization Transformer</title><updated>2021-09-23T09:06:49.511324+00:00</updated><author><name>Ukrit Watchareeruetai</name></author><author><name>Benjaphan Sommanna</name></author><author><name>Sanjana Jain</name></author><author><name>Pavit Noinongyao</name></author><author><name>Ankush Ganguly</name></author><author><name>Aubin Samacoits</name></author><author><name>Samuel W.F. Earp</name></author><author><name>Nakarin Sritrakool</name></author><link href="http://arxiv.org/abs/2109.10057" rel="alternate"/><summary>This paper presents a novel Transformer-based facial landmark localization |
|
|
|
1022 network named Localization Transformer (LOTR). The proposed framework is a |
|
|
|
1023 direct coordinate regression approach leveraging a Transformer network to |
|
|
|
1024 better utilize the spatial information in the feature map. An LOTR model |
|
|
|
1025 consists of three main modules: 1) a visual backbone that converts an input |
|
|
|
1026 image into a feature map, 2) a Transformer module that improves the feature |
|
|
|
1027 representation from the visual backbone, and 3) a landmark prediction head that |
|
|
|
1028 directly predicts the landmark coordinates from the Transformer's |
|
|
|
1029 representation. Given cropped-and-aligned face images, the proposed LOTR can be |
|
|
|
1030 trained end-to-end without requiring any post-processing steps. This paper also |
|
|
|
1031 introduces the smooth-Wing loss function, which addresses the gradient |
|
|
|
1032 discontinuity of the Wing loss, leading to better convergence than standard |
|
|
|
1033 loss functions such as L1, L2, and Wing loss. Experimental results on the JD |
|
|
|
1034 landmark dataset provided by the First Grand Challenge of 106-Point Facial |
|
|
|
1035 Landmark Localization indicate the superiority of LOTR over the existing |
|
|
|
1036 methods on the leaderboard and two recent heatmap-based approaches. |
|
|
|
1037 </summary></entry><entry><id>http://arxiv.org/abs/2109.10047</id><title>Search For Deep Graph Neural Networks</title><updated>2021-09-23T09:06:49.510946+00:00</updated><author><name>Guosheng Feng</name></author><author><name>Chunnan Wang</name></author><author><name>Hongzhi Wang</name></author><link href="http://arxiv.org/abs/2109.10047" rel="alternate"/><summary>Current GNN-oriented NAS methods focus on the search for different layer |
|
|
|
1038 aggregate components with shallow and simple architectures, which are limited |
|
|
|
1039 by the 'over-smooth' problem. To further explore the benefits from structural |
|
|
|
1040 diversity and depth of GNN architectures, we propose a GNN generation pipeline |
|
|
|
1041 with a novel two-stage search space, which aims at automatically generating |
|
|
|
1042 high-performance while transferable deep GNN models in a block-wise manner. |
|
|
|
1043 Meanwhile, to alleviate the 'over-smooth' problem, we incorporate multiple |
|
|
|
1044 flexible residual connection in our search space and apply identity mapping in |
|
|
|
1045 the basic GNN layers. For the search algorithm, we use deep-q-learning with |
|
|
|
1046 epsilon-greedy exploration strategy and reward reshaping. Extensive experiments |
|
|
|
1047 on real-world datasets show that our generated GNN models outperforms existing |
|
|
|
1048 manually designed and NAS-based ones. |
|
|
|
1049 </summary></entry><entry><id>http://arxiv.org/abs/2109.10034</id><title>Learning offline: memory replay in biological and artificial reinforcement learning</title><updated>2021-09-23T09:06:49.510518+00:00</updated><author><name>Emma L. Roscow</name></author><author><name>Raymond Chua</name></author><author><name>Rui Ponte Costa</name></author><author><name>Matt W. Jones</name></author><author><name>Nathan Lepora</name></author><link href="http://arxiv.org/abs/2109.10034" rel="alternate"/><summary>Learning to act in an environment to maximise rewards is among the brain's |
|
|
|
1050 key functions. This process has often been conceptualised within the framework |
|
|
|
1051 of reinforcement learning, which has also gained prominence in machine learning |
|
|
|
1052 and artificial intelligence (AI) as a way to optimise decision-making. A common |
|
|
|
1053 aspect of both biological and machine reinforcement learning is the |
|
|
|
1054 reactivation of previously experienced episodes, referred to as replay. Replay |
|
|
|
1055 is important for memory consolidation in biological neural networks, and is key |
|
|
|
1056 to stabilising learning in deep neural networks. Here, we review recent |
|
|
|
1057 developments concerning the functional roles of replay in the fields of |
|
|
|
1058 neuroscience and AI. Complementary progress suggests how replay might support |
|
|
|
1059 learning processes, including generalisation and continual learning, affording |
|
|
|
1060 opportunities to transfer knowledge across the two fields to advance the |
|
|
|
1061 understanding of biological and artificial learning and memory. |
|
|
|
1062 </summary></entry><entry><id>http://arxiv.org/abs/2109.10020</id><title>Online Multi-horizon Transaction Metric Estimation with Multi-modal Learning in Payment Networks</title><updated>2021-09-23T09:06:49.510005+00:00</updated><author><name>Chin-Chia Michael Yeh</name></author><author><name>Zhongfang Zhuang</name></author><author><name>Junpeng Wang</name></author><author><name>Yan Zheng</name></author><author><name>Javid Ebrahimi</name></author><author><name>Ryan Mercer</name></author><author><name>Liang Wang</name></author><author><name>Wei Zhang</name></author><link href="http://arxiv.org/abs/2109.10020" rel="alternate"/><summary>Predicting metrics associated with entities' transnational behavior within |
|
|
|
1063 payment processing networks is essential for system monitoring. Multivariate |
|
|
|
1064 time series, aggregated from the past transaction history, can provide valuable |
|
|
|
1065 insights for such prediction. The general multivariate time series prediction |
|
|
|
1066 problem has been well studied and applied across several domains, including |
|
|
|
1067 manufacturing, medical, and entomology. However, new domain-related challenges |
|
|
|
1068 associated with the data such as concept drift and multi-modality have surfaced |
|
|
|
1069 in addition to the real-time requirements of handling the payment transaction |
|
|
|
1070 data at scale. In this work, we study the problem of multivariate time series |
|
|
|
1071 prediction for estimating transaction metrics associated with entities in the |
|
|
|
1072 payment transaction database. We propose a model with five unique components to |
|
|
|
1073 estimate the transaction metrics from multi-modality data. Four of these |
|
|
|
1074 components capture interaction, temporal, scale, and shape perspectives, and |
|
|
|
1075 the fifth component fuses these perspectives together. We also propose a hybrid |
|
|
|
1076 offline/online training scheme to address concept drift in the data and fulfill |
|
|
|
1077 the real-time requirements. Combining the estimation model with a graphical |
|
|
|
1078 user interface, the prototype transaction metric estimation system has |
|
|
|
1079 demonstrated its potential benefit as a tool for improving a payment processing |
|
|
|
1080 company's system monitoring capability. |
|
|
|
1081 </summary></entry><entry><id>http://arxiv.org/abs/2109.10016</id><title>CONQUER: Contextual Query-aware Ranking for Video Corpus Moment Retrieval</title><updated>2021-09-23T09:06:49.509605+00:00</updated><author><name>Zhijian Hou</name></author><author><name>Chong-Wah Ngo</name></author><author><name>Wing Kwong Chan</name></author><link href="http://arxiv.org/abs/2109.10016" rel="alternate"/><summary>This paper tackles a recently proposed Video Corpus Moment Retrieval task. |
|
|
|
1082 This task is essential because advanced video retrieval applications should |
|
|
|
1083 enable users to retrieve a precise moment from a large video corpus. We propose |
|
|
|
1084 a novel CONtextual QUery-awarE Ranking~(CONQUER) model for effective moment |
|
|
|
1085 localization and ranking. CONQUER explores query context for multi-modal fusion |
|
|
|
1086 and representation learning in two different steps. The first step derives |
|
|
|
1087 fusion weights for the adaptive combination of multi-modal video content. The |
|
|
|
1088 second step performs bi-directional attention to tightly couple video and query |
|
|
|
1089 as a single joint representation for moment localization. As query context is |
|
|
|
1090 fully engaged in video representation learning, from feature fusion to |
|
|
|
1091 transformation, the resulting feature is user-centered and has a larger |
|
|
|
1092 capacity in capturing multi-modal signals specific to query. We conduct studies |
|
|
|
1093 on two datasets, TVR for closed-world TV episodes and DiDeMo for open-world |
|
|
|
1094 user-generated videos, to investigate the potential advantages of fusing video |
|
|
|
1095 and query online as a joint representation for moment retrieval. |
|
|
|
1096 </summary></entry><entry><id>http://arxiv.org/abs/2109.10011</id><title>Unsupervised Abstract Reasoning for Raven's Problem Matrices</title><updated>2021-09-23T09:06:49.509153+00:00</updated><author><name>Tao Zhuo</name></author><author><name>Qiang Huang</name></author><author><name>Mohan Kankanhalli</name></author><link href="http://arxiv.org/abs/2109.10011" rel="alternate"/><summary>Raven's Progressive Matrices (RPM) is highly correlated with human |
|
|
|
1097 intelligence, and it has been widely used to measure the abstract reasoning |
|
|
|
1098 ability of humans. In this paper, to study the abstract reasoning capability of |
|
|
|
1099 deep neural networks, we propose the first unsupervised learning method for |
|
|
|
1100 solving RPM problems. Since the ground truth labels are not allowed, we design |
|
|
|
1101 a pseudo target based on the prior constraints of the RPM formulation to |
|
|
|
1102 approximate the ground truth label, which effectively converts the unsupervised |
|
|
|
1103 learning strategy into a supervised one. However, the correct answer is wrongly |
|
|
|
1104 labelled by the pseudo target, and thus the noisy contrast will lead to |
|
|
|
1105 inaccurate model training. To alleviate this issue, we propose to improve the |
|
|
|
1106 model performance with negative answers. Moreover, we develop a |
|
|
|
1107 decentralization method to adapt the feature representation to different RPM |
|
|
|
1108 problems. Extensive experiments on three datasets demonstrate that our method |
|
|
|
1109 even outperforms some of the supervised approaches. Our code is available at |
|
|
|
1110 https://github.com/visiontao/ncd. |
|
|
|
1111 </summary></entry><entry><id>http://arxiv.org/abs/2109.10007</id><title>Generating Local Maps of Science using Deep Bibliographic Coupling</title><updated>2021-09-23T09:06:49.508792+00:00</updated><author><name>Gaëlle Candel</name></author><author><name>David Naccache</name></author><link href="http://arxiv.org/abs/2109.10007" rel="alternate"/><summary>Bibliographic and co-citation coupling are two analytical methods widely used |
|
|
|
1112 to measure the degree of similarity between scientific papers. These approaches |
|
|
|
1113 are intuitive, easy to put into practice, and computationally cheap. Moreover, |
|
|
|
1114 they have been used to generate a map of science, allowing visualizing research |
|
|
|
1115 field interactions. Nonetheless, these methods do not work unless two papers |
|
|
|
1116 share a standard reference, limiting the two papers usability with no direct |
|
|
|
1117 connection. In this work, we propose to extend bibliographic coupling to the |
|
|
|
1118 deep neighborhood, by using graph diffusion methods. This method allows |
|
|
|
1119 defining similarity between any two papers, making it possible to generate a |
|
|
|
1120 local map of science, highlighting field organization. |
|
|
|
1121 </summary></entry><entry><id>http://arxiv.org/abs/2109.09975</id><title>Fast nonlinear risk assessment for autonomous vehicles using learned conditional probabilistic models of agent futures</title><updated>2021-09-23T09:06:49.508363+00:00</updated><author><name>Ashkan Jasour</name></author><author><name>Xin Huang</name></author><author><name>Allen Wang</name></author><author><name>Brian C. William</name></author><link href="http://arxiv.org/abs/2109.09975" rel="alternate"/><summary>This paper presents fast non-sampling based methods to assess the risk for |
|
|
|
1122 trajectories of autonomous vehicles when probabilistic predictions of other |
|
|
|
1123 agents' futures are generated by deep neural networks (DNNs). The presented |
|
|
|
1124 methods address a wide range of representations for uncertain predictions |
|
|
|
1125 including both Gaussian and non-Gaussian mixture models to predict both agent |
|
|
|
1126 positions and control inputs conditioned on the scene contexts. We show that |
|
|
|
1127 the problem of risk assessment when Gaussian mixture models (GMMs) of agent |
|
|
|
1128 positions are learned can be solved rapidly to arbitrary levels of accuracy |
|
|
|
1129 with existing numerical methods. To address the problem of risk assessment for |
|
|
|
1130 non-Gaussian mixture models of agent position, we propose finding upper bounds |
|
|
|
1131 on risk using nonlinear Chebyshev's Inequality and sums-of-squares (SOS) |
|
|
|
1132 programming; they are both of interest as the former is much faster while the |
|
|
|
1133 latter can be arbitrarily tight. These approaches only require higher order |
|
|
|
1134 statistical moments of agent positions to determine upper bounds on risk. To |
|
|
|
1135 perform risk assessment when models are learned for agent control inputs as |
|
|
|
1136 opposed to positions, we propagate the moments of uncertain control inputs |
|
|
|
1137 through the nonlinear motion dynamics to obtain the exact moments of uncertain |
|
|
|
1138 position over the planning horizon. To this end, we construct deterministic |
|
|
|
1139 linear dynamical systems that govern the exact time evolution of the moments of |
|
|
|
1140 uncertain position in the presence of uncertain control inputs. The presented |
|
|
|
1141 methods are demonstrated on realistic predictions from DNNs trained on the |
|
|
|
1142 Argoverse and CARLA datasets and are shown to be effective for rapidly |
|
|
|
1143 assessing the probability of low probability events. |
|
|
|
1144 </summary></entry><entry><id>http://arxiv.org/abs/2109.09968</id><title>Generalization in Text-based Games via Hierarchical Reinforcement Learning</title><updated>2021-09-23T09:06:49.507912+00:00</updated><author><name>Yunqiu Xu</name></author><author><name>Meng Fang</name></author><author><name>Ling Chen</name></author><author><name>Yali Du</name></author><author><name>Chengqi Zhang</name></author><link href="http://arxiv.org/abs/2109.09968" rel="alternate"/><summary>Deep reinforcement learning provides a promising approach for text-based |
|
|
|
1145 games in studying natural language communication between humans and artificial |
|
|
|
1146 agents. However, the generalization still remains a big challenge as the agents |
|
|
|
1147 depend critically on the complexity and variety of training tasks. In this |
|
|
|
1148 paper, we address this problem by introducing a hierarchical framework built |
|
|
|
1149 upon the knowledge graph-based RL agent. In the high level, a meta-policy is |
|
|
|
1150 executed to decompose the whole game into a set of subtasks specified by |
|
|
|
1151 textual goals, and select one of them based on the KG. Then a sub-policy in the |
|
|
|
1152 low level is executed to conduct goal-conditioned reinforcement learning. We |
|
|
|
1153 carry out experiments on games with various difficulty levels and show that the |
|
|
|
1154 proposed method enjoys favorable generalizability. |
|
|
|
1155 </summary></entry><entry><id>http://arxiv.org/abs/2109.09960</id><title>Enforcing Mutual Consistency of Hard Regions for Semi-supervised Medical Image Segmentation</title><updated>2021-09-23T09:06:49.507378+00:00</updated><author><name>Yicheng Wu</name></author><author><name>Zongyuan Ge</name></author><author><name>Donghao Zhang</name></author><author><name>Minfeng Xu</name></author><author><name>Lei Zhang</name></author><author><name>Yong Xia</name></author><author><name>Jianfei Cai</name></author><link href="http://arxiv.org/abs/2109.09960" rel="alternate"/><summary>In this paper, we proposed a novel mutual consistency network (MC-Net+) to |
|
|
|
1156 effectively exploit the unlabeled hard regions for semi-supervised medical |
|
|
|
1157 image segmentation. The MC-Net+ model is motivated by the observation that deep |
|
|
|
1158 models trained with limited annotations are prone to output highly uncertain |
|
|
|
1159 and easily mis-classified predictions in the ambiguous regions (e.g. adhesive |
|
|
|
1160 edges or thin branches) for the image segmentation task. Leveraging these |
|
|
|
1161 region-level challenging samples can make the semi-supervised segmentation |
|
|
|
1162 model training more effective. Therefore, our proposed MC-Net+ model consists |
|
|
|
1163 of two new designs. First, the model contains one shared encoder and multiple |
|
|
|
1164 sightly different decoders (i.e. using different up-sampling strategies). The |
|
|
|
1165 statistical discrepancy of multiple decoders' outputs is computed to denote the |
|
|
|
1166 model's uncertainty, which indicates the unlabeled hard regions. Second, a new |
|
|
|
1167 mutual consistency constraint is enforced between one decoder's probability |
|
|
|
1168 output and other decoders' soft pseudo labels. In this way, we minimize the |
|
|
|
1169 model's uncertainty during training and force the model to generate invariant |
|
|
|
1170 and low-entropy results in such challenging areas of unlabeled data, in order |
|
|
|
1171 to learn a generalized feature representation. We compared the segmentation |
|
|
|
1172 results of the MC-Net+ with five state-of-the-art semi-supervised approaches on |
|
|
|
1173 three public medical datasets. Extension experiments with two common |
|
|
|
1174 semi-supervised settings demonstrate the superior performance of our model over |
|
|
|
1175 other existing methods, which sets a new state of the art for semi-supervised |
|
|
|
1176 medical image segmentation. |
|
|
|
1177 </summary></entry><entry><id>http://arxiv.org/abs/2109.09946</id><title>Identifying biases in legal data: An algorithmic fairness perspective</title><updated>2021-09-23T09:06:49.507009+00:00</updated><author><name>Jackson Sargent</name></author><author><name>Melanie Weber</name></author><link href="http://arxiv.org/abs/2109.09946" rel="alternate"/><summary>The need to address representation biases and sentencing disparities in legal |
|
|
|
1178 case data has long been recognized. Here, we study the problem of identifying |
|
|
|
1179 and measuring biases in large-scale legal case data from an algorithmic |
|
|
|
1180 fairness perspective. Our approach utilizes two regression models: A baseline |
|
|
|
1181 that represents the decisions of a "typical" judge as given by the data and a |
|
|
|
1182 "fair" judge that applies one of three fairness concepts. Comparing the |
|
|
|
1183 decisions of the "typical" judge and the "fair" judge allows for quantifying |
|
|
|
1184 biases across demographic groups, as we demonstrate in four case studies on |
|
|
|
1185 criminal data from Cook County (Illinois). |
|
|
|
1186 </summary></entry><entry><id>http://arxiv.org/abs/2109.09906</id><title>Audio Interval Retrieval using Convolutional Neural Networks</title><updated>2021-09-23T09:06:49.506567+00:00</updated><author><name>Ievgeniia Kuzminykh</name></author><author><name>Dan Shevchuk</name></author><author><name>Stavros Shiaeles</name></author><author><name>Bogdan Ghita</name></author><link href="http://arxiv.org/abs/2109.09906" rel="alternate"/><summary>Modern streaming services are increasingly labeling videos based on their |
|
|
|
1187 visual or audio content. This typically augments the use of technologies such |
|
|
|
1188 as AI and ML by allowing to use natural speech for searching by keywords and |
|
|
|
1189 video descriptions. Prior research has successfully provided a number of |
|
|
|
1190 solutions for speech to text, in the case of a human speech, but this article |
|
|
|
1191 aims to investigate possible solutions to retrieve sound events based on a |
|
|
|
1192 natural language query, and estimate how effective and accurate they are. In |
|
|
|
1193 this study, we specifically focus on the YamNet, AlexNet, and ResNet-50 |
|
|
|
1194 pre-trained models to automatically classify audio samples using their |
|
|
|
1195 respective melspectrograms into a number of predefined classes. The predefined |
|
|
|
1196 classes can represent sounds associated with actions within a video fragment. |
|
|
|
1197 Two tests are conducted to evaluate the performance of the models on two |
|
|
|
1198 separate problems: audio classification and intervals retrieval based on a |
|
|
|
1199 natural language query. Results show that the benchmarked models are comparable |
|
|
|
1200 in terms of performance, with YamNet slightly outperforming the other two |
|
|
|
1201 models. YamNet was able to classify single fixed-size audio samples with 92.7% |
|
|
|
1202 accuracy and 68.75% precision while its average accuracy on intervals retrieval |
|
|
|
1203 was 71.62% and precision was 41.95%. The investigated method may be embedded |
|
|
|
1204 into an automated event marking architecture for streaming services. |
|
|
|
1205 </summary></entry><entry><id>http://arxiv.org/abs/2109.09904</id><title>Symbols as a Lingua Franca for Bridging Human-AI Chasm for Explainable and Advisable AI Systems</title><updated>2021-09-23T09:06:49.506026+00:00</updated><author><name>Subbarao Kambhampati</name></author><author><name>Sarath Sreedharan</name></author><author><name>Mudit Verma</name></author><author><name>Yantian Zha</name></author><author><name>Lin Guan</name></author><link href="http://arxiv.org/abs/2109.09904" rel="alternate"/><summary>Despite the surprising power of many modern AI systems that often learn their |
|
|
|
1206 own representations, there is significant discontent about their inscrutability |
|
|
|
1207 and the attendant problems in their ability to interact with humans. While |
|
|
|
1208 alternatives such as neuro-symbolic approaches have been proposed, there is a |
|
|
|
1209 lack of consensus on what they are about. There are often two independent |
|
|
|
1210 motivations (i) symbols as a lingua franca for human-AI interaction and (ii) |
|
|
|
1211 symbols as (system-produced) abstractions use in its internal reasoning. The |
|
|
|
1212 jury is still out on whether AI systems will need to use symbols in their |
|
|
|
1213 internal reasoning to achieve general intelligence capabilities. Whatever the |
|
|
|
1214 answer there is, the need for (human-understandable) symbols in human-AI |
|
|
|
1215 interaction seems quite compelling. Symbols, like emotions, may well not be |
|
|
|
1216 sine qua non for intelligence per se, but they will be crucial for AI systems |
|
|
|
1217 to interact with us humans--as we can neither turn off our emotions nor get by |
|
|
|
1218 without our symbols. In particular, in many human-designed domains, humans |
|
|
|
1219 would be interested in providing explicit (symbolic) knowledge and advice--and |
|
|
|
1220 expect machine explanations in kind. This alone requires AI systems to at least |
|
|
|
1221 do their I/O in symbolic terms. In this blue sky paper, we argue this point of |
|
|
|
1222 view, and discuss research directions that need to be pursued to allow for this |
|
|
|
1223 type of human-AI interaction. |
|
|
|
1224 </summary></entry><entry><id>http://arxiv.org/abs/2109.09889</id><title>A Simple Unified Framework for Anomaly Detection in Deep Reinforcement Learning</title><updated>2021-09-23T09:06:49.505560+00:00</updated><author><name>Hongming Zhang</name></author><author><name>Ke Sun</name></author><author><name>Bo Xu</name></author><author><name>Linglong Kong</name></author><author><name>Martin Müller</name></author><link href="http://arxiv.org/abs/2109.09889" rel="alternate"/><summary>Abnormal states in deep reinforcement learning~(RL) are states that are |
|
|
|
1225 beyond the scope of an RL policy. Such states may make the RL system unsafe and |
|
|
|
1226 impede its deployment in real scenarios. In this paper, we propose a simple yet |
|
|
|
1227 effective anomaly detection framework for deep RL algorithms that |
|
|
|
1228 simultaneously considers random, adversarial and out-of-distribution~(OOD) |
|
|
|
1229 state outliers. In particular, we attain the class-conditional distributions |
|
|
|
1230 for each action class under the Gaussian assumption, and rely on these |
|
|
|
1231 distributions to discriminate between inliers and outliers based on Mahalanobis |
|
|
|
1232 Distance~(MD) and Robust Mahalanobis Distance. We conduct extensive experiments |
|
|
|
1233 on Atari games that verify the effectiveness of our detection strategies. To |
|
|
|
1234 the best of our knowledge, we present the first in-detail study of statistical |
|
|
|
1235 and adversarial anomaly detection in deep RL algorithms. This simple unified |
|
|
|
1236 anomaly detection paves the way towards deploying safe RL systems in real-world |
|
|
|
1237 applications. |
|
|
|
1238 </summary></entry><entry><id>http://arxiv.org/abs/2109.09876</id><title>Context-Specific Representation Abstraction for Deep Option Learning</title><updated>2021-09-23T09:06:49.505061+00:00</updated><author><name>Marwa Abdulhai</name></author><author><name>Dong-Ki Kim</name></author><author><name>Matthew Riemer</name></author><author><name>Miao Liu</name></author><author><name>Gerald Tesauro</name></author><author><name>Jonathan P. How</name></author><link href="http://arxiv.org/abs/2109.09876" rel="alternate"/><summary>Hierarchical reinforcement learning has focused on discovering temporally |
|
|
|
1239 extended actions, such as options, that can provide benefits in problems |
|
|
|
1240 requiring extensive exploration. One promising approach that learns these |
|
|
|
1241 options end-to-end is the option-critic (OC) framework. We examine and show in |
|
|
|
1242 this paper that OC does not decompose a problem into simpler sub-problems, but |
|
|
|
1243 instead increases the size of the search over policy space with each option |
|
|
|
1244 considering the entire state space during learning. This issue can result in |
|
|
|
1245 practical limitations of this method, including sample inefficient learning. To |
|
|
|
1246 address this problem, we introduce Context-Specific Representation Abstraction |
|
|
|
1247 for Deep Option Learning (CRADOL), a new framework that considers both temporal |
|
|
|
1248 abstraction and context-specific representation abstraction to effectively |
|
|
|
1249 reduce the size of the search over policy space. Specifically, our method |
|
|
|
1250 learns a factored belief state representation that enables each option to learn |
|
|
|
1251 a policy over only a subsection of the state space. We test our method against |
|
|
|
1252 hierarchical, non-hierarchical, and modular recurrent neural network baselines, |
|
|
|
1253 demonstrating significant sample efficiency improvements in challenging |
|
|
|
1254 partially observable environments. |
|
|
|
1255 </summary></entry><entry><id>http://arxiv.org/abs/2109.09862</id><title>Language Identification with a Reciprocal Rank Classifier</title><updated>2021-09-23T09:06:49.504540+00:00</updated><author><name>Dominic Widdows</name></author><author><name>Chris Brew</name></author><link href="http://arxiv.org/abs/2109.09862" rel="alternate"/><summary>Language identification is a critical component of language processing |
|
|
|
1256 pipelines (Jauhiainen et al.,2019) and is not a solved problem in real-world |
|
|
|
1257 settings. We present a lightweight and effective language identifier that is |
|
|
|
1258 robust to changes of domain and to the absence of copious training data. |
|
|
|
1259 </summary></entry><entry><id>http://arxiv.org/abs/2109.09861</id><title>Generalized dynamic cognitive hierarchy models for strategic driving behavior</title><updated>2021-09-23T09:06:49.504112+00:00</updated><author><name>Atrisha Sarkar</name></author><author><name>Kate Larson</name></author><author><name>Krzysztof Czarnecki</name></author><link href="http://arxiv.org/abs/2109.09861" rel="alternate"/><summary>While there has been an increasing focus on the use of game theoretic models |
|
|
|
1260 for autonomous driving, empirical evidence shows that there are still open |
|
|
|
1261 questions around dealing with the challenges of common knowledge assumptions as |
|
|
|
1262 well as modeling bounded rationality. To address some of these practical |
|
|
|
1263 challenges, we develop a framework of generalized dynamic cognitive hierarchy |
|
|
|
1264 for both modelling naturalistic human driving behavior as well as behavior |
|
|
|
1265 planning for autonomous vehicles (AV). This framework is built upon a rich |
|
|
|
1266 model of level-0 behavior through the use of automata strategies, an |
|
|
|
1267 interpretable notion of bounded rationality through safety and maneuver |
|
|
|
1268 satisficing, and a robust response for planning. Based on evaluation on two |
|
|
|
1269 large naturalistic datasets as well as simulation of critical traffic |
|
|
|
1270 scenarios, we show that i) automata strategies are well suited for level-0 |
|
|
|
1271 behavior in a dynamic level-k framework, and ii) the proposed robust response |
|
|
|
1272 to a heterogeneous population of strategic and non-strategic reasoners can be |
|
|
|
1273 an effective approach for game theoretic planning in AV. |
|
|
|
1274 </summary></entry><entry><id>http://arxiv.org/abs/2109.09844</id><title>Assessing clinical utility of Machine Learning and Artificial Intelligence approaches to analyze speech recordings in Multiple Sclerosis: A Pilot Study</title><updated>2021-09-23T09:06:49.503318+00:00</updated><author><name>Emil Svoboda</name></author><author><name>Tomáš Bořil</name></author><author><name>Jan Rusz</name></author><author><name>Tereza Tykalová</name></author><author><name>Dana Horáková</name></author><author><name>Charles R.G. Guttman</name></author><author><name>Krastan B. Blagoev</name></author><author><name>Hiroto Hatabu</name></author><author><name>Vlad I. Valtchinov</name></author><link href="http://arxiv.org/abs/2109.09844" rel="alternate"/><summary>Background: An early diagnosis together with an accurate disease progression |
|
|
|
1275 monitoring of multiple sclerosis is an important component of successful |
|
|
|
1276 disease management. Prior studies have established that multiple sclerosis is |
|
|
|
1277 correlated with speech discrepancies. Early research using objective acoustic |
|
|
|
1278 measurements has discovered measurable dysarthria. |
|
|
|
1279 </summary></entry><entry><id>http://arxiv.org/abs/2109.09833</id><title>Revisiting the Characteristics of Stochastic Gradient Noise and Dynamics</title><updated>2021-09-23T09:06:49.502515+00:00</updated><author><name>Yixin Wu</name></author><author><name>Rui Luo</name></author><author><name>Chen Zhang</name></author><author><name>Jun Wang</name></author><author><name>Yaodong Yang</name></author><link href="http://arxiv.org/abs/2109.09833" rel="alternate"/><summary>In this paper, we characterize the noise of stochastic gradients and analyze |
|
|
|
1280 the noise-induced dynamics during training deep neural networks by |
|
|
|
1281 gradient-based optimizers. Specifically, we firstly show that the stochastic |
|
|
|
1282 gradient noise possesses finite variance, and therefore the classical Central |
|
|
|
1283 Limit Theorem (CLT) applies; this indicates that the gradient noise is |
|
|
|
1284 asymptotically Gaussian. Such an asymptotic result validates the wide-accepted |
|
|
|
1285 assumption of Gaussian noise. We clarify that the recently observed phenomenon |
|
|
|
1286 of heavy tails within gradient noise may not be intrinsic properties, but the |
|
|
|
1287 consequence of insufficient mini-batch size; the gradient noise, which is a sum |
|
|
|
1288 of limited i.i.d. random variables, has not reached the asymptotic regime of |
|
|
|
1289 CLT, thus deviates from Gaussian. We quantitatively measure the goodness of |
|
|
|
1290 Gaussian approximation of the noise, which supports our conclusion. Secondly, |
|
|
|
1291 we analyze the noise-induced dynamics of stochastic gradient descent using the |
|
|
|
1292 Langevin equation, granting for momentum hyperparameter in the optimizer with a |
|
|
|
1293 physical interpretation. We then proceed to demonstrate the existence of the |
|
|
|
1294 steady-state distribution of stochastic gradient descent and approximate the |
|
|
|
1295 distribution at a small learning rate. |
|
|
|
1296 </summary></entry><entry><id>http://arxiv.org/abs/2109.09829</id><title>Towards Energy-Efficient and Secure Edge AI: A Cross-Layer Framework</title><updated>2021-09-23T09:06:49.502052+00:00</updated><author><name>Muhammad Shafique</name></author><author><name>Alberto Marchisio</name></author><author><name>Rachmad Vidya Wicaksana Putra</name></author><author><name>Muhammad Abdullah Hanif</name></author><link href="http://arxiv.org/abs/2109.09829" rel="alternate"/><summary>The security and privacy concerns along with the amount of data that is |
|
|
|
1297 required to be processed on regular basis has pushed processing to the edge of |
|
|
|
1298 the computing systems. Deploying advanced Neural Networks (NN), such as deep |
|
|
|
1299 neural networks (DNNs) and spiking neural networks (SNNs), that offer |
|
|
|
1300 state-of-the-art results on resource-constrained edge devices is challenging |
|
|
|
1301 due to the stringent memory and power/energy constraints. Moreover, these |
|
|
|
1302 systems are required to maintain correct functionality under diverse security |
|
|
|
1303 and reliability threats. This paper first discusses existing approaches to |
|
|
|
1304 address energy efficiency, reliability, and security issues at different system |
|
|
|
1305 layers, i.e., hardware (HW) and software (SW). Afterward, we discuss how to |
|
|
|
1306 further improve the performance (latency) and the energy efficiency of Edge AI |
|
|
|
1307 systems through HW/SW-level optimizations, such as pruning, quantization, and |
|
|
|
1308 approximation. To address reliability threats (like permanent and transient |
|
|
|
1309 faults), we highlight cost-effective mitigation techniques, like fault-aware |
|
|
|
1310 training and mapping. Moreover, we briefly discuss effective detection and |
|
|
|
1311 protection techniques to address security threats (like model and data |
|
|
|
1312 corruption). Towards the end, we discuss how these techniques can be combined |
|
|
|
1313 in an integrated cross-layer framework for realizing robust and |
|
|
|
1314 energy-efficient Edge AI systems. |
|
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1315 </summary></entry><entry><id>http://arxiv.org/abs/2109.09825</id><title>Data Augmentation Methods for Anaphoric Zero Pronouns</title><updated>2021-09-23T09:06:49.501641+00:00</updated><author><name>Abdulrahman Aloraini</name></author><author><name>Massimo Poesio</name></author><link href="http://arxiv.org/abs/2109.09825" rel="alternate"/><summary>In pro-drop language like Arabic, Chinese, Italian, Japanese, Spanish, and |
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1316 many others, unrealized (null) arguments in certain syntactic positions can |
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1317 refer to a previously introduced entity, and are thus called anaphoric zero |
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1318 pronouns. The existing resources for studying anaphoric zero pronoun |
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1319 interpretation are however still limited. In this paper, we use five data |
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1320 augmentation methods to generate and detect anaphoric zero pronouns |
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1321 automatically. We use the augmented data as additional training materials for |
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1322 two anaphoric zero pronoun systems for Arabic. Our experimental results show |
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1323 that data augmentation improves the performance of the two systems, surpassing |
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1324 the state-of-the-art results. |
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1325 </summary></entry><entry><id>http://arxiv.org/abs/2109.09809</id><title>Counterfactual Instances Explain Little</title><updated>2021-09-23T09:06:49.501241+00:00</updated><author><name>Adam White</name></author><author><name>Artur d'Avila Garcez</name></author><link href="http://arxiv.org/abs/2109.09809" rel="alternate"/><summary>In many applications, it is important to be able to explain the decisions of |
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1326 machine learning systems. An increasingly popular approach has been to seek to |
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1327 provide \emph{counterfactual instance explanations}. These specify close |
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1328 possible worlds in which, contrary to the facts, a person receives their |
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1329 desired decision from the machine learning system. This paper will draw on |
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1330 literature from the philosophy of science to argue that a satisfactory |
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1331 explanation must consist of both counterfactual instances and a causal equation |
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1332 (or system of equations) that support the counterfactual instances. We will |
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1333 show that counterfactual instances by themselves explain little. We will |
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1334 further illustrate how explainable AI methods that provide both causal |
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1335 equations and counterfactual instances can successfully explain machine |
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1336 learning predictions. |
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1337 </summary></entry><entry><id>http://arxiv.org/abs/2109.09807</id><title>I Know You Can't See Me: Dynamic Occlusion-Aware Safety Validation of Strategic Planners for Autonomous Vehicles Using Hypergames</title><updated>2021-09-23T09:06:49.500759+00:00</updated><author><name>Maximilian Kahn</name></author><author><name>Atrisha Sarkar</name></author><author><name>Krzysztof Czarnecki</name></author><link href="http://arxiv.org/abs/2109.09807" rel="alternate"/><summary>A particular challenge for both autonomous and human driving is dealing with |
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1338 risk associated with dynamic occlusion, i.e., occlusion caused by other |
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1339 vehicles in traffic. Based on the theory of hypergames, we develop a novel |
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1340 multi-agent dynamic occlusion risk (DOR) measure for assessing situational risk |
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1341 in dynamic occlusion scenarios. Furthermore, we present a white-box, |
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1342 scenario-based, accelerated safety validation framework for assessing safety of |
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1343 strategic planners in AV. Based on evaluation over a large naturalistic |
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1344 database, our proposed validation method achieves a 4000% speedup compared to |
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1345 direct validation on naturalistic data, a more diverse coverage, and ability to |
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1346 generalize beyond the dataset and generate commonly observed dynamic occlusion |
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1347 crashes in traffic in an automated manner. |
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1348 </summary></entry><entry><id>http://arxiv.org/abs/2109.09791</id><title>Prediction of severe thunderstorm events with ensemble deep learning and radar data</title><updated>2021-09-23T09:06:49.499746+00:00</updated><author><name>Sabrina Guastavino</name></author><author><name>Michele Piana</name></author><author><name>Marco Tizzi</name></author><author><name>Federico Cassola</name></author><author><name>Antonio Iengo</name></author><author><name>Davide Sacchetti</name></author><author><name>Enrico Solazzo</name></author><author><name>Federico Benvenuto</name></author><link href="http://arxiv.org/abs/2109.09791" rel="alternate"/><summary>The problem of nowcasting extreme weather events can be addressed by applying |
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1349 either numerical methods for the solution of dynamic model equations or |
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1350 data-driven artificial intelligence algorithms. Within this latter framework, |
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1351 the present paper illustrates how a deep learning method, exploiting videos of |
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1352 radar reflectivity frames as input, can be used to realize a warning machine |
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1353 able to sound timely alarms of possible severe thunderstorm events. From a |
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1354 technical viewpoint, the computational core of this approach is the use of a |
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1355 value-weighted skill score for both transforming the probabilistic outcomes of |
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1356 the deep neural network into binary classification and assessing the |
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1357 forecasting performances. The warning machine has been validated against |
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1358 weather radar data recorded in the Liguria region, in Italy, |
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1359 |
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