GenAI4ELab/papercli-papers huggingface dataset:
Cross-Level Distillation and Feature Denoising for Cross-Domain Few-Shot Classification
Authors: Hao ZHENG; Runqi Wang; Jianzhuang Liu; Asako Kanezaki
Venue: ICLR 2023 (ICLR 2023 poster)

Abstract: The conventional few-shot classification aims at learning a model on a large labeled base dataset and rapidly adapting to a target dataset that is from the same distribution as the base dataset. However, in practice, the base and the target datasets of few-shot classification are usually from different domains, which is the problem of cross-domain few-shot classification. We tackle this problem by making a small proportion of unlabeled images in the target domain accessible in the training stage. In this setup, even though the base data are sufficient and labeled, the large domain shift still makes transferring the knowledge from the base dataset difficult. We meticulously design a cross-level knowledge distillation method, which can strengthen the ability of the model to extract more discriminative features in the target dataset by guiding the network's shallow layers to learn higher-level information. Furthermore, in order to alleviate the overfitting in the evaluation stage, we propose a feature denoising operation which can reduce the feature redundancy and mitigate overfitting. Our approach can surpass the previous state-of-the-art method, Dynamic-Distillation, by 5.44% on 1-shot and 1.37% on 5-shot classification tasks on average in the BSCD-FSL benchmark. The implementation code will be available at https://gitee.com/mindspore/models/tree/master/research/cv/CLDFD.
Out-of-Distribution Detection based on In-Distribution Data Patterns Memorization with Modern Hopfield Energy
Authors: Jinsong Zhang; Qiang Fu; Xu Chen; Lun Du; Zelin Li; Gang Wang; xiaoguang Liu; Shi Han; Dongmei Zhang
Venue: ICLR 2023 (ICLR 2023 poster)

Abstract: Out-of-Distribution (OOD) detection is essential for safety-critical applications of deep neural networks. OOD detection is challenging since DNN models may produce very high logits value even for OOD samples. Hence, it is of great difficulty to discriminate OOD data by directly adopting Softmax on output logits as the confidence score. Differently, we detect the OOD sample with Hopfield energy in a store-then-compare paradigm. In more detail, penultimate layer outputs on the training set are considered as the representations of in-distribution (ID) data. Thus they can be transformed into stored patterns that serve as anchors to measure the discrepancy of unseen data for OOD detection. Starting from the energy function defined in Modern Hopfield Network for the discrepancy score calculation, we derive a simplified version SHE with theoretical analysis. In SHE, we utilize only one stored pattern to present each class, and these patterns can be obtained by simply averaging the penultimate layer outputs of training samples within this class. SHE has the advantages of hyperparameterfree
and high computational efficiency. The evaluations of nine widely-used OOD datasets show the promising performance of such a simple yet effective approach and its superiority over State-of-the-Art models. Code is available at https://github.com/zjs975584714/SHE ood detection.
Fair Federated Learning via Bounded Group Loss
Authors: Shengyuan Hu; Steven Wu; Virginia Smith
Venue: ICLR 2023 (Submitted to ICLR 2023)

Abstract: In federated learning, fair prediction across protected groups is an important constraint for many applications. Unfortunately, prior work studying group fair federated learning lacks formal convergence or fairness guarantees. In this work we propose a general framework for provably fair federated learning. In particular, we explore and extend the notion of Bounded Group Loss as a theoretically-grounded approach for group fairness. Using this setup, we propose a scalable federated optimization method that optimizes the empirical risk under a number of group fairness constraints. We provide convergence guarantees for the method as well as fairness guarantees for the resulting solution. Empirically, we evaluate our method across common benchmarks from fair ML and federated learning, showing that it can provide both fairer and more accurate predictions than baseline approaches.
The Power of Feel-Good Thompson Sampling: A Unified Framework for Linear Bandits
Authors: Zhiyuan Fan; Quanquan Gu
Venue: ICLR 2023 (Submitted to ICLR 2023)

Abstract: Linear contextual bandit is one of the most popular models in online decision-making with bandit feedback. Prior work has studied different variants of this model, e.g., misspecified, non-stationary, and multi-task/life-long linear contextual bandits. However, there is no single framework that can unify the algorithm design and analysis for these variants. In this paper, we propose a unified framework for linear contextual bandits based on feel-good Thompson sampling (Zhang, 2021). The algorithm derived from our framework achieves nearly minimax optimal regret in various settings and resolves the respective open problem in each setting. Specifically, let $d$ be the dimension of the context and $T$ be the length of the horizon, our algorithm achieves an $\widetilde{\mathcal{O}}(d\sqrt{ST})$ regret bound for non-stationary linear bandits with at most $S$ switches, $\widetilde{\mathcal{O}}(d^{\frac{5}{6}} T^{\frac{2}{3}} P^{\frac{1}{3}})$ regret for non-stationary linear bandits with bounded path length $P$, and $\widetilde{\mathcal{O}}(d\sqrt{kT} + \sqrt{dkMT})$ regret for (generalized) lifelong linear bandits over $M$ tasks that share an unknown representation of dimension $k$. We believe our framework will shed light on the design and analysis of other linear contextual bandit variants.
Joint Attention-Driven Domain Fusion and Noise-Tolerant Learning for Multi-Source Domain Adaptation
Authors: Tong Xu; Lin Wang; Wu Ning; Chunyan Lyu; Kejun Wang
Venue: ICLR 2023 (Submitted to ICLR 2023)

Abstract: Multi-source Unsupervised Domain Adaptation (MUDA) transfers knowledge from multiple source domains with labeled data to an unlabeled target domain.
Recently, endeavours have been made in establishing connections among different domains to enable feature interaction. However, these approaches essentially enhance category information and thus lack the transfer of the domain-specific information. Moreover, few research has explored the connection between pseudo-label generation and the framework’s learning capabilities, crucial for ensuring robust MUDA. In this paper, we propose a novel framework, which significantly reduces the domain discrepancy and demonstrates new state-of-the-art performance. In particular, we first propose a Contrary Attention-based Domain Merge (CADM) module to enable the interaction among the features so as to achieve the mixture of domain-specific information instead of focusing on the category information. Secondly, to enable the network to correct the pseudo labels during training, we propose an adaptive and reverse cross-entropy loss, which can adaptively impose constraints on the pseudo-label generation process. We conduct experiments on four benchmark datasets, showing that our approach can efficiently fuse all domains for MUDA while showing much better performance than the prior methods.
Uncertainty and Traffic Light Aware Pedestrian Crossing Intention Prediction
Authors: Minali Upreti; Jayanth Ramesh; Chandan R Kumar; Bodhisattwa Chakraborty; VIKRAM BALISAVIRA; Phillip Czech; Vitali Kaiser; Markus Roth
Venue: ICLR 2023 (Submitted to ICLR 2023)

Abstract: Predicting Vulnerable Road User (VRU) crossing intention is one of the major challenges in automated driving. Crossing intention prediction systems trained only on pedestrian features underperform in situations that are most obvious to humans, as the latter take additional context features into consideration. Moreover, such systems tend to be over-confident for out-of-distribution samples, therefore making them less reliable to be used by downstream tasks like sensor fusion and trajectory planning for automated vehicles. In this work, we demonstrate that the results of crossing intention prediction systems can be improved by incorporating traffic light status as an additional input. Further, we make the model robust and interpretable by estimating uncertainty. Experiments on the PIE dataset show that the F1-score improved from 0.77 to 0.82 and above for three different baseline systems when considering traffic-light context. By adding uncertainty, we show increased uncertainty values for out-of-distribution samples, therefore leading to interpretable and reliable predictions of crossing intention.
Scaling Pareto-Efficient Decision Making via Offline Multi-Objective RL
Authors: Baiting Zhu; Meihua Dang; Aditya Grover
Venue: ICLR 2023 (ICLR 2023 poster)

Abstract: The goal of multi-objective reinforcement learning (MORL) is to learn policies that simultaneously optimize multiple competing objectives. In practice, an agent's preferences over the objectives may not be known apriori, and hence, we require policies that can generalize to arbitrary preferences at test time. In this work, we propose a new data-driven setup for offline MORL, where we wish to learn a preference-agnostic policy agent using only a finite dataset of offline demonstrations of other agents and their preferences. The key contributions of this work are two-fold. First, we introduce D4MORL, (D)atasets for MORL that are specifically designed for offline settings. It contains 1.8 million annotated demonstrations obtained by rolling out reference policies that optimize for randomly sampled preferences on 6 MuJoCo environments with 2-3 objectives each. Second, we propose Pareto-Efficient Decision Agents (PEDA), a family of offline MORL algorithms that builds and extends Decision Transformers via a novel preference-and-return-conditioned policy. Empirically, we show that PEDA closely approximates the behavioral policy on the D4MORL benchmark and provides an excellent approximation of the Pareto-front with appropriate conditioning, as measured by the hypervolume and sparsity metrics.
Automating Nearest Neighbor Search Configuration with Constrained Optimization
Authors: Philip Sun; Ruiqi Guo; Sanjiv Kumar
Venue: ICLR 2023 (ICLR 2023 poster)

Abstract: The approximate nearest neighbor (ANN) search problem is fundamental to efficiently serving many real-world machine learning applications. A number of techniques have been developed for ANN search that are efficient, accurate, and scalable. However, such techniques typically have a number of parameters that affect the speed-recall tradeoff, and exhibit poor performance when such parameters aren't properly set. Tuning these parameters has traditionally been a manual process, demanding in-depth knowledge of the underlying search algorithm. This is becoming an increasingly unrealistic demand as ANN search grows in popularity. To tackle this obstacle to ANN adoption, this work proposes a constrained optimization-based approach to tuning quantization-based ANN algorithms. Our technique takes just a desired search cost or recall as input, and then generates tunings that, empirically, are very close to the speed-recall Pareto frontier and give leading performance on standard benchmarks.
CANIFE: Crafting Canaries for Empirical Privacy Measurement in Federated Learning
Authors: Samuel Maddock; Alexandre Sablayrolles; Pierre Stock
Venue: ICLR 2023 (ICLR 2023 poster)

Abstract: Federated Learning (FL) is a setting for training machine learning models in distributed environments where the clients do not share their raw data but instead send model updates to a server. However, model updates can be subject to attacks and leak private information. Differential Privacy (DP) is a leading mitigation strategy which involves adding noise to clipped model updates, trading off performance for strong theoretical privacy guarantees. Previous work has shown that the threat model of DP is conservative and that the obtained guarantees may be vacuous or may overestimate information leakage in practice. In this paper, we aim to achieve a tighter measurement of the model exposure by considering a realistic threat model. We propose a novel method, CANIFE, that uses canaries - carefully crafted samples by a strong adversary to evaluate the empirical privacy of a training round. We apply this attack to vision models trained on CIFAR-10 and CelebA and to language models trained on Sent140 and Shakespeare. In particular, in realistic FL scenarios, we demonstrate that the empirical per-round epsilon obtained with CANIFE is 4 -- 5$\times$ lower than the theoretical bound.
Statistical Inference for Fisher Market Equilibrium
Authors: Luofeng Liao; Yuan Gao; Christian Kroer
Venue: ICLR 2023 (ICLR 2023 poster)

Abstract: Statistical inference under market equilibrium effects has attracted increasing attention recently. In this paper we focus on the specific case of linear Fisher markets. They have been widely use in fair resource allocation of food/blood donations and budget management in large-scale Internet ad auctions. In resource allocation, it is crucial to quantify the variability of the resource received by the agents (such as blood banks and food banks) in addition to fairness and efficiency properties of the systems. For ad auction markets, it is important to establish statistical properties of the platform's revenues in addition to their expected values. To this end, we propose a statistical framework based on the concept of infinite-dimensional Fisher markets. In our framework, we observe a market formed by a finite number of items sampled from an underlying distribution (the ``observed market'') and aim to infer several important equilibrium quantities of the underlying long-run market. These equilibrium quantities include individual utilities, social welfare, and pacing multipliers. Through the lens of sample average approximation (SSA), we derive a collection of statistical results and show that the observed market provides useful statistical information of the long-run market. In other words, the equilibrium quantities of the observed market converge to the true ones of the long-run market with strong statistical guarantees. These include consistency, finite sample bounds, asymptotics, and confidence. As an extension, we discuss revenue inference in quasilinear Fisher markets.
High-Precision Regressors for Particle Physics
Authors: Fady Bishara; Ayan Paul; Jennifer Dy
Venue: ICLR 2023 (Submitted to ICLR 2023)

Abstract: Monte Carlo simulations of physics processes at particle colliders like the Large Hadron Collider at CERN take up a major fraction of the computational budget. For some simulations, a single data point takes seconds, minutes, or even hours to compute from first principles. Since the necessary number of data points per simulation is on the order of $10^9$ -- $10^{12}$, machine learning regressors can be used in place of physics simulators to significantly reduce this computational burden. However, this task requires high precision regressors that can deliver data with relative errors less than 1\% or even 0.1\% over the entire domain of the function. In this paper, we develop optimal training strategies and tune various machine learning regressors to satisfy the high-precision requirement. We leverage symmetry arguments from particle physics to optimize the performance of the regressors. Inspired by ResNets, we design a Deep Neural Network with skip connections that outperform fully connected Deep Neural Networks. We find that at lower dimensions, boosted decision trees far outperform neural networks while at higher dimensions neural networks perform better. We show that these regressors can speed up simulations by a factor of $10^3$ -- $10^6$ over the first-principles computations currently used in Monte Carlo simulations. Additionally, using symmetry arguments derived from particle physics, we reduce the number of regressors necessary for each simulation by an order of magnitude. Our work can significantly reduce the training and storage burden of Monte Carlo simulations at current and future collider experiments.
Calibrating the Rigged Lottery: Making All Tickets Reliable
Authors: Bowen Lei; Ruqi Zhang; Dongkuan Xu; Bani Mallick
Venue: ICLR 2023 (ICLR 2023 poster)

Abstract: Although sparse training has been successfully used in various deep learning tasks to save memory and reduce inference time, the reliability of the produced sparse models remains unexplored. Previous research has shown that deep neural networks tend to be over-confident, and we find that sparse training exacerbates this problem. Therefore, calibrating the sparse models is crucial for reliable prediction and decision making. In this paper, we propose a new sparse training method to produce sparse models with improved confidence calibration. In contrast to previous research that uses only one mask to control the sparse topology, our method utilizes two masks, including a deterministic mask and a random mask. The former efficiently searches and activates important weights by exploiting the magnitude of weights and gradients. While the latter brings better exploration and finds more appropriate weight values by random updates. Theoretically, we prove our method can be viewed as a hierarchical variational approximation of a probabilistic deep Gaussian process. Extensive experiments on multiple datasets, model architectures, and sparsities show that our method can reduce ECE values by up to 47.8\% and simultaneously maintain or even improve accuracy with only a slight increase in computational and storage burden.
PEER: A Collaborative Language Model
Authors: Timo Schick; Jane A. Yu; Zhengbao Jiang; Fabio Petroni; Patrick Lewis; Gautier Izacard; Qingfei You; Christoforos Nalmpantis; Edouard Grave; Sebastian Riedel
Venue: ICLR 2023 (ICLR 2023 notable top 25%)

Abstract: Textual content is often the output of a collaborative writing process: We start with an initial draft, ask for suggestions, and repeatedly make changes.
Agnostic of this process, today’s language models are trained to generate only the final result. As a consequence, they lack several abilities crucial for collaborative writing: They are unable to update existing texts, difficult to control and incapable of verbally planning or explaining their actions.
To address these shortcomings, we introduce PEER, a collaborative language model that is trained to imitate the entire writing process itself. PEER can write drafts, add suggestions, propose edits and provide explanations for its actions. Crucially, we train multiple instances of PEER able to infill various parts of the writing process, enabling the use of self-training techniques for increasing the quality, amount and diversity of training data. This unlocks PEER's full potential by making it applicable in domains for which no edit histories are available and improving its ability to follow instructions, to write useful comments, and to explain its actions. We show that PEER achieves strong performance across various domains and editing tasks.
Multi-Agent Policy Transfer via Task Relationship Modeling
Authors: Rong-Jun Qin; Feng Chen; Tonghan Wang; Lei Yuan; Xiaoran Wu; Yipeng Kang; Zongzhang Zhang; Chongjie Zhang; Yang Yu
Venue: ICLR 2023 (Submitted to ICLR 2023)

Abstract: Team adaptation to new cooperative tasks is a hallmark of human intelligence, which has yet to be fully realized in learning agents. Previous works on multi-agent transfer learning accommodate teams of different sizes, but heavily rely on the generalization ability of neural networks for adapting to unseen tasks. We posit that the relationship among tasks provides the key information for policy adaptation. To utilize such relationship for efficient transfer, we try to discover and exploit the knowledge among tasks from different teams, propose to learn effect-based task representations as a common latent space among tasks, and use it to build an alternatively fixed training scheme. We demonstrate that the task representation can capture the relationship among teams and generalize to unseen tasks. As a result, the proposed method can help transfer learned cooperation knowledge to new tasks after training on a few source tasks, and the learned transferred policies can also help solve tasks that are hard to learn from scratch.
Efficient Approximations of Complete Interatomic Potentials for Crystal Property Prediction
Authors: Yuchao Lin; Keqiang Yan; Youzhi Luo; Yi Liu; Xiaoning Qian; Shuiwang Ji
Venue: ICLR 2023 (Submitted to ICLR 2023)

Abstract: We study the problem of crystal material property prediction. A crystal structure consists of a minimal unit cell that is repeated infinitely in 3D space. How to accurately represent such repetitive structures in machine learning models remains unresolved. Current methods construct graphs by establishing edges only between nearby nodes, thereby failing to faithfully capture infinite repeating patterns and distant interatomic interactions. In this work, we propose several innovations to overcome these limitations. First, we propose to model physics-principled interatomic potentials directly instead of only using distances as in existing methods. These potentials include the Coulomb potential, London dispersion potential, and Pauli repulsion potential. Second, we propose to model the complete set of potentials among all atoms, instead of only between nearby atoms as in prior methods. This is enabled by our approximations of infinite potential summations with provable error bounds. We further develop efficient algorithms to compute the approximations. Finally, we propose to incorporate our computations of complete interatomic potentials into message passing neural networks for representation learning. We perform experiments on the JARVIS and Materials Project benchmarks for evaluation. Results show that the use of complete interatomic potentials leads to consistent performance improvements with reasonable computational costs.
CEREAL: Few-Sample Clustering Evaluation
Authors: Nihal V. Nayak; Ethan R. Elenberg; Clemens Rosenbaum
Venue: ICLR 2023 (Submitted to ICLR 2023)

Abstract: Evaluating clustering quality with reliable evaluation metrics like normalized mutual information (NMI) requires labeled data that can be expensive to annotate. We focus on the underexplored problem of estimating clustering quality with limited labels. We adapt existing approaches from the few-sample model evaluation literature to actively sub-sample, with a learned surrogate model, the most informative data points for annotation to estimate the evaluation metric. However, we find that their estimation  can be biased and only relies on the labeled data. To that end, we introduce CEREAL, a comprehensive framework for few-sample clustering evaluation that extends active sampling approaches in three key ways. First, we propose novel NMI-based acquisition functions that account for the distinctive properties of clustering and uncertainties from a learned surrogate model. Next, we use ideas from semi-supervised learning and train the surrogate model with both the labeled and unlabeled data. Finally, we pseudo-label the unlabeled data with the surrogate model. We run experiments to estimate NMI in an active sampling pipeline on three datasets across vision and language. Our results show that CEREAL reduces the area under the absolute error curve by up to 57% compared to the best sampling baseline. We perform an extensive ablation study to show that our framework is agnostic to the choice of clustering algorithm and evaluation metric. We also extend CEREAL from clusterwise annotations to pairwise annotations. Overall, CEREAL can efficiently evaluate clustering with limited human annotations.