集中式培训（CT）是许多受欢迎的多代理增强学习（MARL）方法的基础，因为它允许代理商快速学习高性能的政策。但是，CT依靠代理人从对特定州对其他代理商的行为的一次性观察中学习。由于MARL代理商在培训期间探索和更新其政策，因此这些观察结果通常会为其他代理商的行为和预期的给定行动回报提供不良的预测。因此，CT方法患有较高的差异和容易出错的估计，从而损害了学习。除非施加了强大的分解限制，否则CT方法还遭受了复杂性爆炸性增长（例如，QMIX的单调奖励函数）。我们通过一个新的半居中的MAL框架来应对这些挑战，该框架执行政策安装的培训和分散的执行。我们的方法是嵌入式增强学习算法（PERLA），是参与者批评的MARL算法的增强工具，它利用了一种新型参数共享协议和策略嵌入方法来维持对其他代理商的行为的估计。我们的理论证明，佩拉大大降低了价值估计的差异。与各种CT方法不同，Perla无缝地采用MARL算法，它可以轻松地与代理数量缩放，而无需限制性分解假设。我们展示了Perla在基准环境中的出色经验表现和有效的缩放，包括Starcraft Micromagement II和Multi-Agent Mujoco

学习协作对于多机构增强学习（MARL）至关重要。以前的作品通过最大化代理行为的相关性来促进协作，该行为的相关性通常以不同形式的相互信息（MI）为特征。但是，我们揭示了次最佳的协作行为，也出现了强烈的相关性，并且简单地最大化MI可以阻碍学习的学习能力。为了解决这个问题，我们提出了一个新颖的MARL框架，称为“渐进式信息协作（PMIC）”，以进行更有效的MI驱动协作。 PMIC使用全球国家和联合行动之间MI测量的新协作标准。基于此标准，PMIC的关键思想是最大程度地提高与优越的协作行为相关的MI，并最大程度地减少与下等方面相关的MI。这两个MI目标通过促进更好的合作，同时避免陷入次级优势，从而扮演互补的角色。与其他算法相比，在各种MARL基准测试的实验表明，PMIC的表现出色。

虽然深增强学习已成为连续决策问题的有希望的机器学习方法，但对于自动驾驶或医疗应用等高利害域来说仍然不够成熟。在这种情况下，学习的政策需要例如可解释，因此可以在任何部署之前检查它（例如，出于安全性和验证原因）。本调查概述了各种方法，以实现加固学习（RL）的更高可解释性。为此，我们将解释性（作为模型的财产区分开来和解释性（作为HOC操作后的讲话，通过代理的干预），并在RL的背景下讨论它们，并强调前概念。特别是，我们认为可译文的RL可能会拥抱不同的刻面：可解释的投入，可解释（转型/奖励）模型和可解释的决策。根据该计划，我们总结和分析了与可解释的RL相关的最近工作，重点是过去10年来发表的论文。我们还简要讨论了一些相关的研究领域并指向一些潜在的有前途的研究方向。

基于模型的强化学习方法在许多任务中实现了显着的样本效率，但它们的性能通常受模型错误的存在限制。为减少模型错误，以前的作品使用单一设计的网络来符合整个环境动态，将环境动态视为黑匣子。然而，这些方法缺乏考虑动态可能包含多个子动态的环境分解性，这可以单独建模，允许我们更准确地构建世界模型。在本文中，我们提出了环境动态分解（ED2），这是一种以分解方式模拟环境的新型世界模型施工框架。 ED2包含两个关键组件：子动力学发现（SD2）和动态分解预测（D2P）。 SD2发现环境中的子动力学，然后D2P构建子动力学后的分解世界模型。 ED2可以容易地与现有的MBRL算法和经验结果表明，ED2显着降低了模型误差，并提高了各种任务上最先进的MBRL算法的性能。

深度强化学习（DRL）和深度多机构的强化学习（MARL）在包括游戏AI，自动驾驶汽车，机器人技术等各种领域取得了巨大的成功。但是，众所周知，DRL和Deep MARL代理的样本效率低下，即使对于相对简单的问题设置，通常也需要数百万个相互作用，从而阻止了在实地场景中的广泛应用和部署。背后的一个瓶颈挑战是众所周知的探索问题，即如何有效地探索环境和收集信息丰富的经验，从而使政策学习受益于最佳研究。在稀疏的奖励，吵闹的干扰，长距离和非平稳的共同学习者的复杂环境中，这个问题变得更加具有挑战性。在本文中，我们对单格和多代理RL的现有勘探方法进行了全面的调查。我们通过确定有效探索的几个关键挑战开始调查。除了上述两个主要分支外，我们还包括其他具有不同思想和技术的著名探索方法。除了算法分析外，我们还对一组常用基准的DRL进行了全面和统一的经验比较。根据我们的算法和实证研究，我们终于总结了DRL和Deep Marl中探索的公开问题，并指出了一些未来的方向。

奖励成型（RS）是克服稀疏或不信息奖励问题的强大方法（RL）。但是，RS通常依赖于手动设计的成型奖励功能，其构造耗时且容易出错。它还需要与自主学习目标相反的领域知识。我们介绍了增强学习优化塑造算法（ROSA）的增强型，这是一个自动化的RS框架，其中塑造奖励函数是在两个代理之间的新型马尔可夫游戏中构建的。奖励塑料代理（Shaper）使用切换控件来确定在其他代理（控制器）使用这些形状奖励的任务中学习任务的最佳策略，以确定要添加形状奖励及其最佳值的状态。我们证明，Rosa很容易采用现有的RL算法，学会了构建针对任务的塑造奖励功能，从而确保有效地收敛到高性能策略。我们在三个经过精心设计的实验中展示了罗莎（Rosa）在挑战稀疏奖励环境中对最先进的RS算法的优越性能。

Dataset distillation has emerged as a prominent technique to improve data efficiency when training machine learning models. It encapsulates the knowledge from a large dataset into a smaller synthetic dataset. A model trained on this smaller distilled dataset can attain comparable performance to a model trained on the original training dataset. However, the existing dataset distillation techniques mainly aim at achieving the best trade-off between resource usage efficiency and model utility. The security risks stemming from them have not been explored. This study performs the first backdoor attack against the models trained on the data distilled by dataset distillation models in the image domain. Concretely, we inject triggers into the synthetic data during the distillation procedure rather than during the model training stage, where all previous attacks are performed. We propose two types of backdoor attacks, namely NAIVEATTACK and DOORPING. NAIVEATTACK simply adds triggers to the raw data at the initial distillation phase, while DOORPING iteratively updates the triggers during the entire distillation procedure. We conduct extensive evaluations on multiple datasets, architectures, and dataset distillation techniques. Empirical evaluation shows that NAIVEATTACK achieves decent attack success rate (ASR) scores in some cases, while DOORPING reaches higher ASR scores (close to 1.0) in all cases. Furthermore, we conduct a comprehensive ablation study to analyze the factors that may affect the attack performance. Finally, we evaluate multiple defense mechanisms against our backdoor attacks and show that our attacks can practically circumvent these defense mechanisms.

Blind image quality assessment (BIQA) remains challenging due to the diversity of distortion and image content variation, which complicate the distortion patterns crossing different scales and aggravate the difficulty of the regression problem for BIQA. However, existing BIQA methods often fail to consider multi-scale distortion patterns and image content, and little research has been done on learning strategies to make the regression model produce better performance. In this paper, we propose a simple yet effective Progressive Multi-Task Image Quality Assessment (PMT-IQA) model, which contains a multi-scale feature extraction module (MS) and a progressive multi-task learning module (PMT), to help the model learn complex distortion patterns and better optimize the regression issue to align with the law of human learning process from easy to hard. To verify the effectiveness of the proposed PMT-IQA model, we conduct experiments on four widely used public datasets, and the experimental results indicate that the performance of PMT-IQA is superior to the comparison approaches, and both MS and PMT modules improve the model's performance.

The development of social media user stance detection and bot detection methods rely heavily on large-scale and high-quality benchmarks. However, in addition to low annotation quality, existing benchmarks generally have incomplete user relationships, suppressing graph-based account detection research. To address these issues, we propose a Multi-Relational Graph-Based Twitter Account Detection Benchmark (MGTAB), the first standardized graph-based benchmark for account detection. To our knowledge, MGTAB was built based on the largest original data in the field, with over 1.55 million users and 130 million tweets. MGTAB contains 10,199 expert-annotated users and 7 types of relationships, ensuring high-quality annotation and diversified relations. In MGTAB, we extracted the 20 user property features with the greatest information gain and user tweet features as the user features. In addition, we performed a thorough evaluation of MGTAB and other public datasets. Our experiments found that graph-based approaches are generally more effective than feature-based approaches and perform better when introducing multiple relations. By analyzing experiment results, we identify effective approaches for account detection and provide potential future research directions in this field. Our benchmark and standardized evaluation procedures are freely available at: https://github.com/GraphDetec/MGTAB.

Given the increasingly intricate forms of partial differential equations (PDEs) in physics and related fields, computationally solving PDEs without analytic solutions inevitably suffers from the trade-off between accuracy and efficiency. Recent advances in neural operators, a kind of mesh-independent neural-network-based PDE solvers, have suggested the dawn of overcoming this challenge. In this emerging direction, Koopman neural operator (KNO) is a representative demonstration and outperforms other state-of-the-art alternatives in terms of accuracy and efficiency. Here we present KoopmanLab, a self-contained and user-friendly PyTorch module of the Koopman neural operator family for solving partial differential equations. Beyond the original version of KNO, we develop multiple new variants of KNO based on different neural network architectures to improve the general applicability of our module. These variants are validated by mesh-independent and long-term prediction experiments implemented on representative PDEs (e.g., the Navier-Stokes equation and the Bateman-Burgers equation) and ERA5 (i.e., one of the largest high-resolution data sets of global-scale climate fields). These demonstrations suggest the potential of KoopmanLab to be considered in diverse applications of partial differential equations.