GenAI4ELab/papercli-papers huggingface dataset:
Auditing Fairness Online through Interactive Refinement
Authors: Pranav Maneriker; Codi Jay Burley; srinivasan parthasarathy
Venue: ICLR 2023 (Submitted to ICLR 2023)

Abstract: Machine learning algorithms are increasingly being deployed for high-stakes scenarios. A sizeable proportion of currently deployed models make their decisions in a black box manner. Such decision-making procedures are susceptible to intrinsic biases, which has led to a call for accountability in deployed decision systems. In this work, we focus on user-specified accountability of decision-making processes of black box systems. Previous work has formulated this problem as run time fairness monitoring over decision functions. However, formulating appropriate specifications for situation-appropriate fairness metrics is challenging. We construct AVOIR, an automated inference-based optimization system that improves bounds for and generalizes prior work across a wide range of fairness metrics. AVOIR offers an interactive and iterative process for exploring fairness violations aligned with governance and regulatory requirements. Our bounds improve over previous probabilistic guarantees for such fairness grammars in online settings. We also construct a novel visualization mechanism that can be used to investigate the context of reported fairness violations and guide users towards meaningful and compliant fairness specifications. We then conduct case studies with fairness metrics on three different datasets and demonstrate how the visualization and improved optimization can detect fairness violations more efficiently and ameliorate the issues with faulty fairness metric design.
Grassmannian Class Representation in Deep Learning
Authors: Haoqi Wang; Zhizhong Li; Wayne Zhang
Venue: ICLR 2023 (Submitted to ICLR 2023)

Abstract: We generalize the class representative vector found in deep classification networks to linear subspaces and show that the new formulation enables the simultaneous enhancement of the inter-class discrimination and intra-class feature variation. Traditionally, the logit is computed by the inner product between a feature and the class vector. In our modeling, classes are subspaces and the logit is defined as the norm of the projection from a feature onto the subspace. Since the set of subspaces forms Grassmann manifolds, finding the optimal subspace representation for classes is to optimize the loss on a Grassmannian. We integrate the Riemannian SGD into existing deep learning frameworks such that the class subspaces in a Grassmannian are jointly optimized with other model parameters in Euclidean. Compared to the vector form, subspaces have two appealing properties: they can be multi-dimensional and they are scaleless. Empirically, we reveal that these distinct characteristics improve various tasks. (1) Image classification. The new formulation brings the top-1 accuracy of ResNet50-D on ImageNet-1K from 78.04% to 79.37% using the standard augmentation in 100 training epochs. This confirms that the representative capability of subspaces is more powerful than vectors. (2) Feature transfer. Subspaces provide freedom for features to vary and we observed that the intra-class variability of features increases when the subspace dimensions are larger. Consequently, the quality of features is better for downstream tasks. The average transfer accuracy across 6 datasets improves from 77.98% to 80.12% compared to the strong baseline of vanilla softmax. (3) Long-tail classification. The scaleless property of subspaces benefits classification in the long-tail scenario and improves the accuracy of ImageNet-LT from 46.83% to 48.94% compared to the standard formulation. With these encouraging results, we believe that more applications could benefit from the Grassmannian class representation. Codes will be released.
Explicitly Maintaining Diverse Playing Styles in Self-Play
Authors: Yuan Liu; Ruimin Shen; Miqing Li; Yingfeng Chen; Juan Zou; Changjie Fan
Venue: ICLR 2023 (Submitted to ICLR 2023)

Abstract: Self-play has proven to be an effective training schema to obtain a high-level agent in complex games through iteratively playing against an opponent from its historical versions. However, its training process may prevent it from generating a well-generalised policy since the trained agent rarely encounters diversely-behaving opponents along its own historical path. In this paper, we aim to improve the generalisation of the policy by maintaining a population of agents with diverse playing styles and high skill levels throughout the training process. Specifically, we propose a bi-objective optimisation model to simultaneously optimise the agents' skill level and playing style. A feature of this model is that we do not regard the skill level and playing style as two objectives to maximise directly since they are not equally important (i.e., agents with diverse playing styles but low skill levels are meaningless). Instead, we create a meta bi-objective model to enable high-level agents with diverse playing styles more likely to be incomparable (i.e. Pareto non-dominated), thereby playing against each other through the training process. We then present an evolutionary algorithm working with the proposed model. Experiments in a classic table tennis game Pong and a commercial role-playing game Justice Online show that our algorithm can learn a well generalised policy and at the same time is able to provide a set of high-level policies with various playing styles.
SARNET: SARCASM VS TRUE-HATE DETECTION NETWORK
Authors: Harsh Mittal; Kartikeya Singh Chauhan; Anil Singh Parihar; Kavinder Singh; Ashutosh Pandey
Venue: ICLR 2023 (Submitted to ICLR 2023)

Abstract: At times hate speech detection classifiers miss the context of a sentence and flag a sarcastic tweet incorrectly. To tackle this problem by emphasising on the context of a tweet we propose SarNet. SarNet is a two-fold deep learning based model which follows a quasi-ternary labelling strategy and contextually classifies a tweet as hate, sarcastic or neither. The first module of SarNet is an ANN-BiLSTM based Pyramid Network used to calculate the hate and sarcastic probabilities of a sentence. The second module of the SarNet is the Nash Equalizer which stems from the concept of game theory and prisoner’s dilemma. It treats hate and sarcasm as two prisoners. A payoff matrix is constructed to calculate the true hate of the tweet. True hate considers the hate part of a tweet excluding the sarcastic part of the tweet. Thus, this gives a true estimate of the hate content in a tweet thereby decreasing the number of sarcastic tweets being falsely flagged as hate. Our proposed model is trained on state-of-the-art hate speech and sarcasm datasets in the English language. The precision, recall and F1 score of our proposed model is 0.93, 0.84 and 0.88 respectively. Comparison with state-of-the-art architectures demonstrated better performance of SarNet by a significant margin.
Homotopy Learning of Parametric Solutions to Constrained Optimization Problems
Authors: Shimiao Li; Jan Drgona; Aaron R Tuor; Larry Pileggi; Draguna L Vrabie
Venue: ICLR 2023 (Submitted to ICLR 2023)

Abstract: Building deep learning (DL) alternatives to constrained optimization problems has been proposed as a cheaper solution approach than classical constrained optimization solvers. However, these approximate learning-based solutions still suffer from constraint violations. From this perspective, reaching a reliable convergence remains an open challenge to DL models even with state-of-the-art methods to impose constraints, especially when facing a large set of nonlinear constraints forming a non-convex feasible set. In this paper, we propose the use of homotopy meta-optimization heuristics which creates a continuous transformation of the objective and constraints during training, to promote a more reliable convergence where the solution feasibility can be further improved. The method developed in this work includes 1) general-purpose homotopy heuristics based on the relaxation of objectives and constraint bounds to enlarge the basin of attraction and 2) physics-informed transformation of domain problem leading to trivial starting points lying within the basin of attraction.  Experimentally, we demonstrate the efficacy of the proposed method on a set of abstract constrained optimization problems and real-world power grid optimal power flow problems with increasing complexity. Results show that constrained deep learning models with homotopy heuristics can improve the feasibility of the resulting solutions while achieving near-optimal objective values when compared with non-homotopy counterparts.
AutoGT: Automated Graph Transformer Architecture Search
Authors: Zizhao Zhang; Xin Wang; Chaoyu Guan; Ziwei Zhang; Haoyang Li; Wenwu Zhu
Venue: ICLR 2023 (ICLR 2023 notable top 5%)

Abstract: Although Transformer architectures have been successfully applied to graph data with the advent of Graph Transformer, current design of Graph Transformer still heavily relies on human labor and expertise knowledge to decide proper neural architectures and suitable graph encoding strategies at each Transformer layer. In literature, there have been some works on automated design of Transformers focusing on non-graph data such as texts and images without considering graph encoding strategies, which fail to handle the non-euclidean graph data. In this paper, we study the problem of automated graph Transformer, for the first time. However, solving these problems poses the following challenges: i) how can we design a unified search space for graph Transformer, and ii) how to deal with the coupling relations between Transformer architectures and the graph encodings of each Transformer layer. To address these challenges, we propose Automated Graph Transformer (AutoGT), a neural architecture search framework that can automatically discover the optimal graph Transformer architectures by joint optimization of Transformer architecture and graph encoding strategies. Specifically, we first propose a unified graph Transformer formulation that can represent most of state-of-the-art graph Transformer architectures. Based upon the unified formulation, we further design the graph Transformer search space that includes both candidate architectures and various graph encodings. To handle the coupling relations, we propose a novel encoding-aware performance estimation strategy by gradually training and splitting the supernets according to the correlations between graph encodings and architectures. The proposed strategy can provide a more consistent and fine-grained performance prediction when evaluating the jointly optimized graph encodings and architectures. Extensive experiments and ablation studies show that our proposed AutoGT gains sufficient improvement over state-of-the-art hand-crafted baselines on all datasets, demonstrating its effectiveness and wide applicability.
Towards Skilled Population Curriculum for MARL
Authors: Rundong Wang; Longtao Zheng; Wei Qiu; Bowei He; Bo An; Zinovi Rabinovich; Yujing Hu; Yingfeng Chen; Tangjie Lv; Changjie Fan
Venue: ICLR 2023 (Submitted to ICLR 2023)

Abstract: Recent advances in multi-agent reinforcement learning (MARL) allow agents to coordinate their behaviors in complex environments. However, common MARL algorithms still suffer from scalability and sparse reward issues. One promising approach to resolve them is automated curriculum learning (ACL), where a student (curriculum learner) train on tasks of increasing difficulty controlled by a teacher (curriculum generator). Unfortunately, in spite of its success, ACL’s applicability is restricted due to: (1) lack of a general student framework to deal with the varying number of agents across tasks and the sparse reward problem, and (2) the non-stationarity in the teacher’s task due to the ever-changing student strategies. As a remedy for ACL, we introduce a novel automatic curriculum learning framework, Skilled Population Curriculum (SPC), adapting curriculum learning to multi-agent coordination. To be specific, we endow the student with population-invariant communication and a hierarchical skill set. Thus, the student can learn cooperation and behavior skills from distinct tasks with a varying number of agents. In addition, we model the teacher as a contextual bandit conditioned by student policies. As a result, a team of agents can change its size while retaining previously acquired skills. We also analyze the inherent non-stationarity of this multi-agent automatic curriculum teaching problem, and provide a corresponding regret bound. Empirical results show that our method improves scalability, sample efficiency, and generalization in multiple MARL environments. The source code and the video can be found at https://sites.google.com/view/marl-spc/.
Context Autoencoder for Self-Supervised Representation Learning
Authors: Xiaokang Chen; Mingyu Ding; Xiaodi Wang; Ying Xin; Shentong Mo; Yunhao Wang; Shumin Han; Ping Luo; Gang Zeng; Jingdong Wang
Venue: ICLR 2023 (Submitted to ICLR 2023)

Abstract: We present a novel masked image modeling (MIM) approach, context autoencoder (CAE), for self-supervised representation pretraining. The goal is to pretrain an encoder by solving the pretext task: estimate the masked patches from the visible patches in an image. Our approach first feeds the visible patches into the encoder, extracting the representations. Then, we make predictions from visible patches to masked patches in the encoded representation space. We introduce an alignment constraint, encouraging that the representations for masked patches, predicted from the encoded representations of visible patches, are aligned with the masked patch presentations computed from the encoder. In other words, the predicted representations are expected to lie in the encoded representation space, which empirically shows the benefit to representation learning. Last, the predicted masked patch representations are mapped to the targets of the pretext task through a decoder.
One additional characteristic is that our approach encourages the separation of the representation learning part (encoder), and the pretext task completion part that will be replaced by the downstream task part. In contrast, previous MIM methods (e.g., BEiT and MAE) couple the two parts, potentially limiting the representation learning quality. We demonstrate the effectiveness of our CAE through superior transfer performance in downstream tasks: semantic segmentation, and object detection and instance segmentation.
Graph Signal Sampling for Inductive One-Bit Matrix Completion: a Closed-form Solution
Authors: Chao Chen; Haoyu Geng; Gang Zeng; Zhaobing Han; Hua Chai; Xiaokang Yang; Junchi Yan
Venue: ICLR 2023 (ICLR 2023 poster)

Abstract: Inductive one-bit matrix completion is motivated by modern applications such as recommender systems, where new users would appear at test stage with the ratings consisting of only ones and no zeros. We propose a unified graph signal sampling framework which enjoys the benefits of graph signal analysis and processing. The key idea is to transform each user's ratings on the items to a function (signal) on the vertices of an item-item graph, then learn structural graph properties to recover the function from its values on certain vertices --- the problem of graph signal sampling. We propose a class of regularization functionals that takes into account discrete random label noise in the graph vertex domain, then develop the GS-IMC approach which biases the reconstruction towards functions that vary little between adjacent vertices for noise reduction. Theoretical result shows that accurate reconstructions can be achieved under mild conditions. For the online setting, we develop a Bayesian extension, i.e., BGS-IMC which considers continuous random Gaussian noise in the graph Fourier domain and builds upon a prediction-correction update algorithm to obtain the unbiased and minimum-variance reconstruction. Both GS-IMC and BGS-IMC have closed-form solutions and thus are highly scalable in large data. Experiments show that our methods achieve state-of-the-art performance on public benchmarks.
Mixture of Quantized Experts (MoQE): Complementary Effect of Low-bit Quantization and Robustness
Authors: Young Jin Kim; Raffy Fahim; Hany Hassan
Venue: ICLR 2023 (Submitted to ICLR 2023)

Abstract: Large Mixture of Experts (MoE) models could achieve state-of-the-art quality on various language tasks, including machine translation task, thanks to the efficient model scaling capability with expert parallelism. However, it has brought a fundamental issue of larger memory consumption at deployment time. Furthermore, this results in significant inference speed degradation at auto-regressive decoding steps due to the increased memory transfers. In this paper, we propose a simple weight-only quantization method using ultra low-bit such as 2-bit, 3-bit and 4-bits to effectively mitigate the increased memory and latency issues of MoE models. We show that low-bit quantization together with the MoE architecture delivers a reliable model performance while reducing the memory size significantly even without any additional training. Especially, expert layers in MoE models are much more robust to the quantization than conventional feedforward networks (FFN) layers. In our comprehensive analysis, we show that MoE models with 2-bit and 80\% sparse expert weights can deliver better model performance than the dense model trained on the same dataset. We present how quantization of different parts of models affects the performance with various experiments using a large MoE model (5.3 B). As a result of low-bit quantization, we show the model size can be reduced by 4.9X smaller than the original half precision floating point (fp16) MoE model. This cuts down the model size of 5.3B parameters from 8.4x of the dense model to only 1.7x of the dense model after 2-bit quantization. It still preserves 1.88\% higher accuracy than the dense model. Combined with an optimized GPU runtime implementation, it also achieves 2.7X speed-up which is even slightly faster than the FLOPs equivalent dense model.
Self-Supervised Off-Policy Ranking via Crowd Layer
Authors: Pengjie Gu; Mengchen Zhao; Jianye HAO; Bo An
Venue: ICLR 2023 (Submitted to ICLR 2023)

Abstract: Off-policy evaluation (OPE) aims to estimate the online performance of target policies given dataset collected by some behavioral policies. OPE is crucial in many applications where online policy evaluation is expensive. However, existing OPE methods are far from reliable. Fortunately, in many real-world scenarios, we care only about the ranking of the evaluating policies, rather than their exact online performance. Existing works on off-policy ranking (OPR) adopt a supervised training paradigm, which assumes that there are plenty of deployed policies and the labels of their performance are available. However, this assumption does not apply to most OPE scenarios because collecting such training data might be highly expensive. In this paper, we propose a novel OPR framework called SOCCER, where the existing OPE methods are modeled as workers in a crowdsourcing system. SOCCER can be trained in a self-supervised way as it does not require any ground-truth labels of policies. Moreover, in order to capture the relative discrepancies between policies, we propose a novel transformer-based architecture to learn effective pairwise policy representations. Experimental results show that SOCCER achieves significantly high accuracy in a variety of OPR tasks. Surprisingly, SOCCER even performs better than baselines trained in a supervised way using additional labeled data, which further demonstrates the superiority of SOCCER in OPR tasks.
Estimating Treatment Effects using Neurosymbolic Program Synthesis
Authors: Abbavaram Gowtham Reddy; Vineeth N. Balasubramanian
Venue: ICLR 2023 (Submitted to ICLR 2023)

Abstract: Estimating treatment effects from observational data is a central problem in causal inference. Methods to solve this problem exploit inductive biases and heuristics from causal inference to design multi-head neural network architectures and regularizers. In this work, we propose to use neurosymbolic program synthesis, a data-efficient, and interpretable technique, to solve the treatment effect estimation problem. We theoretically show that neurosymbolic programming can solve the treatment effect estimation problem. By designing a Domain Specific Language (DSL) for treatment effect estimation based on the inductive biases used in literature, we argue that neurosymbolic programming is a better alternative to treatment effect estimation than traditional models. Our empirical study reveals that our model, which implicitly encodes inductive biases in a DSL, achieves better performance on benchmark datasets than the state-of-the-art models.
Teacher Guided Training: An Efficient Framework for Knowledge Transfer
Authors: Manzil Zaheer; Ankit Singh Rawat; Seungyeon Kim; Chong You; Himanshu Jain; Andreas Veit; Rob Fergus; Sanjiv Kumar
Venue: ICLR 2023 (ICLR 2023 poster)

Abstract: The remarkable performance gains realized by large pretrained models, e.g., GPT-3, hinge on the massive amounts of data they are exposed to during training. Analogously, distilling such large models to compact models for efficient deployment also necessitates a large amount of (labeled or unlabeled) training data. In this paper, we propose the teacher-guided training (TGT) framework for training a high-quality compact model that leverages the knowledge acquired by pretrained generative models, while obviating the need to go through a large volume of data. TGT exploits the fact that the teacher has acquired a good representation of the underlying data domain, which typically corresponds to a much lower dimensional manifold than the input space. Furthermore, we can use the teacher to explore input space more efficiently through sampling or gradient-based methods; thus, making TGT especially attractive for limited data or long-tail settings. We formally capture this benefit of proposed data-domain exploration in our generalization bounds. We find that TGT can improve accuracy on several image classification benchmarks as well as a range of text classification and retrieval tasks.
UNDERSTANDING HTML WITH LARGE LANGUAGE MODELS
Authors: Izzeddin Gur; Ofir Nachum; Yingjie Miao; Mustafa Safdari; Austin V Huang; Sharan Narang; Aakanksha Chowdhery; Noah Fiedel; Aleksandra Faust
Venue: ICLR 2023 (Submitted to ICLR 2023)

Abstract: Large language models (LLM) have shown exceptional performance on a variety of natural language tasks. Yet, their capabilities for HTML understanding – i.e., parsing the raw HTML of a webpage, with applications to automation of web-based tasks, crawling, and browser-assisted retrieval – have not been fully explored. We contribute HTML understanding models (fine-tuned LLMs) and an in-depth analysis of their capabilities under three tasks: (i) Semantic Classification of HTML elements, (ii) Description Generation for HTML inputs, and (iii) Autonomous Web Navigation of HTML pages. While previous work has developed dedicated architectures and training procedures for HTML understanding, we show that LLMs pretrained on standard natural language corpora transfer remarkably well to HTML understanding tasks. For instance, fine-tuned LLMs are 12% more accurate at semantic classification compared to models trained exclusively on the task dataset. Moreover, when fine-tuned on data from the MiniWoB benchmark, LLMs successfully complete 50% more tasks using 192x less data compared to the previous best supervised model. To promote further research on LLMs for HTML understanding, we create and open-source a large-scale HTML dataset distilled and auto-labeled from CommonCrawl. We show evidence that T5-based models due to the bidirectional encoder-decoder architecture are the best choice and that for practitioners larger models are not necessarily better.