We introduce camouflaged data poisoning attacks, a new attack vector that arises in the context of machine unlearning and other settings when model retraining may be induced. An adversary first adds a few carefully crafted points to the training dataset such that the impact on the model's predictions is minimal. The adversary subsequently triggers a request to remove a subset of the introduced points at which point the attack is unleashed and the model's predictions are negatively affected. In particular, we consider clean-label targeted attacks (in which the goal is to cause the model to misclassify a specific test point) on datasets including CIFAR-10, Imagenette, and Imagewoof. This attack is realized by constructing camouflage datapoints that mask the effect of a poisoned dataset.
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在线学习和决策中的一个核心问题 - 从土匪到强化学习 - 是要了解哪种建模假设会导致样本有效的学习保证。我们考虑了一个普遍的对抗性决策框架,该框架涵盖了(结构化的)匪徒问题,这些问题与对抗性动力学有关。我们的主要结果是通过新的上限和下限显示决策估计系数,这是Foster等人引入的复杂度度量。在与我们环境的随机对应物中,对于对抗性决策而言是必要和足够的遗憾。但是,与随机设置相比,必须将决策估计系数应用于所考虑的模型类(或假设)的凸壳。这就确定了容纳对抗奖励或动态的价格受凸层化模型类的行为的约束,并恢复了许多现有结果 - 既积极又负面。在获得这些保证的途径中,我们提供了新的结构结果,将决策估计系数与其他众所周知的复杂性度量的变体联系起来,包括Russo和Van Roy的信息比以及Lattimore和Gy的探索目标\“ {o} rgy。
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我们研究了通过功能近似的强化学习,以部分可观察到的马尔可夫决策过程(POMDP),其中状态空间和观察空间很大甚至连续。特别是,我们考虑了POMDP的Hilbert空间嵌入,其中潜在状态的特征和观察的特征允许观测发射过程的有条件的希尔伯特空间嵌入,而潜在状态过渡是确定性的。在函数近似设置下,最佳潜在状态行动$ q $函数在状态功能中是线性的,而最佳$ q $ - 功能具有差距,我们提供了\ emph {计算和统计上有效} algorithm查找\ emph {确切的最佳}策略。我们在观察空间上的算法和特征的固有维度上,在多项式上显示了算法的计算和统计复杂性。此外,我们显示了确定性的潜在过渡和差距假设对于避免统计复杂性指数在地平线或维度中是必要的。由于我们的保证对状态和观察空间的大小没有明确的依赖性,因此我们的算法可证明对大规模POMDPS。
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我们研究使用功能近似的部分可观察到的动力学系统的增强学习。我们提出了一个新的\ textit {部分可观察到的双线性actor-Critic-Critic框架},它足以包括可观察到的图表部分可观察到的Markov决策过程(POMDPS),可观察到的线性Quadratic-Quadratic-Gaussian(LQG)(LQG),预测状态表示(POMDPS)( PSRS),以及新引入的模型Hilbert空间嵌入POMDPS和可观察到的POMDP,具有潜在的低级过渡。在此框架下,我们提出了一种能够执行不可知论政策学习的参与者批评算法。给定一个由基于内存的策略组成的策略类别(查看最近观察的固定长度窗口),以及一个值得将内存和未来观察作为输入的功能组成的值函数类别,我们的算法学会了与最佳的最佳竞争在给定策略类中基于内存的策略。对于某些示例,例如可观察到的表格pomdps,可观察到的LQG和可观察到的具有潜在低级过渡的可观察到的POMDP,通过隐式利用其特殊特性,我们的算法甚至能够与全球最佳策略竞争,而无需支付对高度依赖的依赖,以竞争全球最佳的策略。它的样本复杂性。
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Epsilon-Greedy,SoftMax或Gaussian噪声等近视探索政策在某些强化学习任务中无法有效探索,但是在许多其他方面,它们的表现都很好。实际上,实际上,由于简单性,它们通常被选为最佳选择。但是,对于哪些任务执行此类政策成功?我们可以为他们的有利表现提供理论保证吗?尽管这些政策具有显着的实际重要性,但这些关键问题几乎没有得到研究。本文介绍了对此类政策的理论分析,并为通过近视探索提供了对增强学习的首次遗憾和样本复杂性。我们的结果适用于具有有限的Bellman Eluder维度的情节MDP中的基于价值功能的算法。我们提出了一种新的复杂度度量,称为近视探索差距,用Alpha表示,该差距捕获了MDP的结构属性,勘探策略和给定的值函数类别。我们表明,近视探索的样品复杂性与该数量的倒数1 / alpha^2二次地量表。我们通过具体的例子进一步证明,由于相应的动态和奖励结构,在近视探索成功的几项任务中,近视探索差距确实是有利的。
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State-of-the-art pre-trained language models (PLMs) outperform other models when applied to the majority of language processing tasks. However, PLMs have been found to degrade in performance under distribution shift, a phenomenon that occurs when data at test-time does not come from the same distribution as the source training set. Equally as challenging is the task of obtaining labels in real-time due to issues like long-labeling feedback loops. The lack of adequate methods that address the aforementioned challenges constitutes the need for approaches that continuously adapt the PLM to a distinct distribution. Unsupervised domain adaptation adapts a source model to an unseen as well as unlabeled target domain. While some techniques such as data augmentation can adapt models in several scenarios, they have only been sparsely studied for addressing the distribution shift problem. In this work, we present an approach (MEMO-CL) that improves the performance of PLMs at test-time under distribution shift. Our approach takes advantage of the latest unsupervised techniques in data augmentation and adaptation to minimize the entropy of the PLM's output distribution. MEMO-CL operates on a batch of augmented samples from a single observation in the test set. The technique introduced is unsupervised, domain-agnostic, easy to implement, and requires no additional data. Our experiments result in a 3% improvement over current test-time adaptation baselines.
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Building an AI agent that can design on its own has been a goal since the 1980s. Recently, deep learning has shown the ability to learn from large-scale data, enabling significant advances in data-driven design. However, learning over prior data limits us only to solve problems that have been solved before and biases data-driven learning towards existing solutions. The ultimate goal for a design agent is the ability to learn generalizable design behavior in a problem space without having seen it before. We introduce a self-learning agent framework in this work that achieves this goal. This framework integrates a deep policy network with a novel tree search algorithm, where the tree search explores the problem space, and the deep policy network leverages self-generated experience to guide the search further. This framework first demonstrates an ability to discover high-performing generative strategies without any prior data, and second, it illustrates a zero-shot generalization of generative strategies across various unseen boundary conditions. This work evaluates the effectiveness and versatility of the framework by solving multiple versions of two engineering design problems without retraining. Overall, this paper presents a methodology to self-learn high-performing and generalizable problem-solving behavior in an arbitrary problem space, circumventing the needs for expert data, existing solutions, and problem-specific learning.
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Large language models (LLMs) have been shown to be able to perform new tasks based on a few demonstrations or natural language instructions. While these capabilities have led to widespread adoption, most LLMs are developed by resource-rich organizations and are frequently kept from the public. As a step towards democratizing this powerful technology, we present BLOOM, a 176B-parameter open-access language model designed and built thanks to a collaboration of hundreds of researchers. BLOOM is a decoder-only Transformer language model that was trained on the ROOTS corpus, a dataset comprising hundreds of sources in 46 natural and 13 programming languages (59 in total). We find that BLOOM achieves competitive performance on a wide variety of benchmarks, with stronger results after undergoing multitask prompted finetuning. To facilitate future research and applications using LLMs, we publicly release our models and code under the Responsible AI License.
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Privacy, security, and bandwidth constraints have led to federated learning (FL) in wireless systems, where training a machine learning (ML) model is accomplished collaboratively without sharing raw data. Often, such collaborative FL strategies necessitate model aggregation at a server. On the other hand, decentralized FL necessitates that participating clients reach a consensus ML model by exchanging parameter updates. In this work, we propose the over-the-air clustered wireless FL (CWFL) strategy, which eliminates the need for a strong central server and yet achieves an accuracy similar to the server-based strategy while using fewer channel uses as compared to decentralized FL. We theoretically show that the convergence rate of CWFL per cluster is O(1/T) while mitigating the impact of noise. Using the MNIST and CIFAR datasets, we demonstrate the accuracy performance of CWFL for the different number of clusters across communication rounds.
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Recent developments in the methods of explainable AI (XAI) methods allow researchers to explore the inner workings of deep neural networks (DNNs), revealing crucial information about input-output relationships and realizing how data connects with machine learning models. In this paper we explore interpretability of DNN models designed to identify jets coming from top quark decay in high energy proton-proton collisions at the Large Hadron Collider (LHC). We review a subset of existing top tagger models and explore different quantitative methods to identify which features play the most important roles in identifying the top jets. We also investigate how and why feature importance varies across different XAI metrics, how feature correlations impact their explainability, and how latent space representations encode information as well as correlate with physically meaningful quantities. Our studies uncover some major pitfalls of existing XAI methods and illustrate how they can be overcome to obtain consistent and meaningful interpretation of these models. We additionally illustrate the activity of hidden layers as Neural Activation Pattern (NAP) diagrams and demonstrate how they can be used to understand how DNNs relay information across the layers and how this understanding can help to make such models significantly simpler by allowing effective model reoptimization and hyperparameter tuning. By incorporating observations from the interpretability studies, we obtain state-of-the-art top tagging performance from augmented implementation of existing network
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