In many real-world applications of reinforcement learning (RL), performing actions requires consuming certain types of resources that are non-replenishable in each episode. Typical applications include robotic control with limited energy and video games with consumable items. In tasks with non-replenishable resources, we observe that popular RL methods such as soft actor critic suffer from poor sample efficiency. The major reason is that, they tend to exhaust resources fast and thus the subsequent exploration is severely restricted due to the absence of resources. To address this challenge, we first formalize the aforementioned problem as a resource-restricted reinforcement learning, and then propose a novel resource-aware exploration bonus (RAEB) to make reasonable usage of resources. An appealing feature of RAEB is that, it can significantly reduce unnecessary resource-consuming trials while effectively encouraging the agent to explore unvisited states. Experiments demonstrate that the proposed RAEB significantly outperforms state-of-the-art exploration strategies in resource-restricted reinforcement learning environments, improving the sample efficiency by up to an order of magnitude.

Model-free deep reinforcement learning (RL) algorithms have been demonstrated on a range of challenging decision making and control tasks. However, these methods typically suffer from two major challenges: very high sample complexity and brittle convergence properties, which necessitate meticulous hyperparameter tuning. Both of these challenges severely limit the applicability of such methods to complex, real-world domains. In this paper, we propose soft actor-critic, an offpolicy actor-critic deep RL algorithm based on the maximum entropy reinforcement learning framework. In this framework, the actor aims to maximize expected reward while also maximizing entropy. That is, to succeed at the task while acting as randomly as possible. Prior deep RL methods based on this framework have been formulated as Q-learning methods. By combining off-policy updates with a stable stochastic actor-critic formulation, our method achieves state-of-the-art performance on a range of continuous control benchmark tasks, outperforming prior on-policy and off-policy methods. Furthermore, we demonstrate that, in contrast to other off-policy algorithms, our approach is very stable, achieving very similar performance across different random seeds.

Reinforcement learning (RL) gained considerable attention by creating decision-making agents that maximize rewards received from fully observable environments. However, many real-world problems are partially or noisily observable by nature, where agents do not receive the true and complete state of the environment. Such problems are formulated as partially observable Markov decision processes (POMDPs). Some studies applied RL to POMDPs by recalling previous decisions and observations or inferring the true state of the environment from received observations. Nevertheless, aggregating observations and decisions over time is impractical for environments with high-dimensional continuous state and action spaces. Moreover, so-called inference-based RL approaches require large number of samples to perform well since agents eschew uncertainty in the inferred state for the decision-making. Active inference is a framework that is naturally formulated in POMDPs and directs agents to select decisions by minimising expected free energy (EFE). This supplies reward-maximising (exploitative) behaviour in RL, with an information-seeking (exploratory) behaviour. Despite this exploratory behaviour of active inference, its usage is limited to discrete state and action spaces due to the computational difficulty of the EFE. We propose a unified principle for joint information-seeking and reward maximization that clarifies a theoretical connection between active inference and RL, unifies active inference and RL, and overcomes their aforementioned limitations. Our findings are supported by strong theoretical analysis. The proposed framework's superior exploration property is also validated by experimental results on partial observable tasks with high-dimensional continuous state and action spaces. Moreover, the results show that our model solves reward-free problems, making task reward design optional.

基于模型的增强学习算法，其目的是学习环境模型，以制定决策，比其无模型的对应物更高。基于模型的方法的样本效率依赖于该模型是否能够良好地近似环境。然而，学习准确的模型是具有挑战性的，特别是在复杂和嘈杂的环境中。为了解决这个问题，我们提出了基于保守的模型的演员 - 评论家（CMBAC），这是一种新的方法，可以实现高样本效率，而无需强烈依赖准确学习模型。具体地，CMBAC从一组不准确模型中了解Q值函数的多个估计，并使用底部K估计的平均值 - 保守估计 - 以优化策略。 CMBAC的吸引人特征是，保守估计有效地鼓励代理人避免不可靠的“有希望的行动” - 其价值在仅小部分模型中。实验表明，CMBAC在几个具有挑战性任务的样本效率方面显着优于最先进的方法，并且该方法比嘈杂环境中的先前方法更强大。

钢筋学习的最新进展证明了其在超级人类水平上解决硬质孕代环境互动任务的能力。然而，由于大多数RL最先进的算法的样本低效率，即，需要大量培训集，因此在实际和现实世界任务中的应用目前有限。例如，在Dota 2中击败人类参与者的Openai五种算法已经训练了数千年的游戏时间。存在解决样本低效问题的几种方法，可以通过更好地探索环境来提供更有效的使用或旨在获得更相关和多样化的经验。然而，为了我们的知识，没有用于基于模型的算法的这种方法，其在求解具有高维状态空间的硬控制任务方面的高采样效率。这项工作连接了探索技术和基于模型的加强学习。我们设计了一种新颖的探索方法，考虑了基于模型的方法的特征。我们还通过实验证明我们的方法显着提高了基于模型的算法梦想家的性能。

在本文中，我们提出了一种用于增强学习（RL）的最大熵框架，以克服在无模型基于样本的学习中实现最大熵RL的软演员 - 评论权（SAC）算法的限制。尽管在未来的最大熵RL指南学习政策中，未来的高熵达到国家，所提出的MAX-MIN熵框架旨在学会访问低熵的国家，并最大限度地提高这些低熵状态的熵，以促进更好的探索。对于一般马尔可夫决策过程（MDP），基于勘探和剥削的解剖学，在提议的MAX-MIN熵框架下构建了一种有效的算法。数值结果表明，该算法对目前最先进的RL算法产生了剧烈性能改进。

Hierarchical Reinforcement Learning (HRL) algorithms have been demonstrated to perform well on high-dimensional decision making and robotic control tasks. However, because they solely optimize for rewards, the agent tends to search the same space redundantly. This problem reduces the speed of learning and achieved reward. In this work, we present an Off-Policy HRL algorithm that maximizes entropy for efficient exploration. The algorithm learns a temporally abstracted low-level policy and is able to explore broadly through the addition of entropy to the high-level. The novelty of this work is the theoretical motivation of adding entropy to the RL objective in the HRL setting. We empirically show that the entropy can be added to both levels if the Kullback-Leibler (KL) divergence between consecutive updates of the low-level policy is sufficiently small. We performed an ablative study to analyze the effects of entropy on hierarchy, in which adding entropy to high-level emerged as the most desirable configuration. Furthermore, a higher temperature in the low-level leads to Q-value overestimation and increases the stochasticity of the environment that the high-level operates on, making learning more challenging. Our method, SHIRO, surpasses state-of-the-art performance on a range of simulated robotic control benchmark tasks and requires minimal tuning.

探索对于具有高维观察和稀疏奖励的复杂环境中的深度强化学习至关重要。为了解决这个问题，最新的方法旨在利用内在的奖励来改善勘探，例如基于新颖的探索和基于预测的探索。但是，许多固有的奖励模块需要复杂的结构和表示学习，从而导致了过度的计算复杂性和不稳定的性能。在本文中，我们提出了一种有益的情节访问差异（REVD），这是一种计算有效且量化的探索方法。更具体地说，REVD通过评估情节之间的基于R \'Enyi Divergence的访问差异来提供内在的奖励。为了进行有效的差异估计，使用随机定义状态编码器使用K-Nearest邻居估计器。最后，在Pybullet机器人环境和Atari游戏上测试了REVD。广泛的实验表明，REVD可以显着提高强化学习算法的样本效率，并优于基准测定方法。

深度加强学习（DRL）的框架为连续决策提供了强大而广泛适用的数学形式化。本文提出了一种新的DRL框架，称为\ emph {$ f $-diveliventcence加强学习（frl）}。在FRL中，通过最大限度地减少学习政策和采样策略之间的$ F $同时执行策略评估和政策改进阶段，这与旨在最大化预期累计奖励的传统DRL算法不同。理论上，我们证明最小化此类$ F $ - 可以使学习政策会聚到最佳政策。此外，我们将FRL框架中的培训代理程序转换为通过Fenchel Concugate的特定$ F $函数转换为鞍点优化问题，这构成了政策评估和政策改进的新方法。通过数学证据和经验评估，我们证明FRL框架有两个优点：（1）政策评估和政策改进过程同时进行，（2）高估价值函数的问题自然而缓解。为了评估FRL框架的有效性，我们对Atari 2600的视频游戏进行实验，并显示在FRL框架中培训的代理匹配或超越基线DRL算法。

无模型的深度增强学习（RL）已成功应用于挑战连续控制域。然而，较差的样品效率可防止这些方法广泛用于现实世界领域。我们通过提出一种新的无模型算法，现实演员 - 评论家（RAC）来解决这个问题，旨在通过学习关于Q函数的各种信任的政策家庭来解决价值低估和高估之间的权衡。我们构建不确定性惩罚Q-Learning（UPQ），该Q-Learning（UPQ）使用多个批评者的合并来控制Q函数的估计偏差，使Q函数平稳地从低于更高的置信范围偏移。随着这些批评者的指导，RAC采用通用价值函数近似器（UVFA），同时使用相同的神经网络学习许多乐观和悲观的政策。乐观的政策会产生有效的探索行为，而悲观政策会降低价值高估的风险，以确保稳定的策略更新和Q函数。该方法可以包含任何违规的演员 - 评论家RL算法。我们的方法实现了10倍的样本效率和25 \％的性能改进与SAC在最具挑战性的人形环境中，获得了11107美元的集中奖励1107美元，价格为10 ^ 6美元。所有源代码都可以在https://github.com/ihuhuhu/rac获得。

Intrinsic motivation is a promising exploration technique for solving reinforcement learning tasks with sparse or absent extrinsic rewards. There exist two technical challenges in implementing intrinsic motivation: 1) how to design a proper intrinsic objective to facilitate efficient exploration; and 2) how to combine the intrinsic objective with the extrinsic objective to help find better solutions. In the current literature, the intrinsic objectives are all designed in a task-agnostic manner and combined with the extrinsic objective via simple addition (or used by itself for reward-free pre-training). In this work, we show that these designs would fail in typical sparse-reward continuous control tasks. To address the problem, we propose Constrained Intrinsic Motivation (CIM) to leverage readily attainable task priors to construct a constrained intrinsic objective, and at the same time, exploit the Lagrangian method to adaptively balance the intrinsic and extrinsic objectives via a simultaneous-maximization framework. We empirically show, on multiple sparse-reward continuous control tasks, that our CIM approach achieves greatly improved performance and sample efficiency over state-of-the-art methods. Moreover, the key techniques of our CIM can also be plugged into existing methods to boost their performances.

几乎可以肯定（或使用概率）满足安全限制对于在现实生活中的增强学习（RL）的部署至关重要。例如，理想情况下，平面降落和起飞应以概率为单位发生。我们通过引入安全增强（SAUTE）马尔可夫决策过程（MDP）来解决该问题，在该过程中，通过将其扩大到州空间并重塑目标来消除安全限制。我们表明，Saute MDP满足了Bellman方程，并使我们更加接近解决安全的RL，几乎可以肯定地满足。我们认为，Saute MDP允许从不同的角度查看安全的RL问题，从而实现新功能。例如，我们的方法具有插件的性质，即任何RL算法都可以“炒”。此外，国家扩展允许跨安全限制进行政策概括。我们最终表明，当约束满意度非常重要时，SAUTE RL算法的表现可以胜过其最先进的对应物。

在本文中，我们介绍了潜在的探索（LGE），这是一种基于探索加固学习（RL）的探索范式的简单而通用的方法。最初引入了Go-explore，并具有强大的域知识约束，以将状态空间划分为单元。但是，在大多数实际情况下，从原始观察中汲取域知识是复杂而乏味的。如果细胞分配不足以提供信息，则可以完全无法探索环境。我们认为，可以通过利用学习的潜在表示，可以将Go-explore方法推广到任何环境，而无需细胞。因此，我们表明LGE可以灵活地与学习潜在表示的任何策略相结合。我们表明，LGE虽然比Go-explore更简单，但在多个硬探索环境上纯粹的探索方面，更强大，并且优于所有最先进的算法。 LGE实现可在https://github.com/qgallouedec/lge上作为开源。

深层确定性的非政策算法的类别有效地用于解决具有挑战性的连续控制问题。但是，当前的方法使用随机噪声作为一种常见的探索方法，该方法具有多个弱点，例如需要对给定任务进行手动调整以及在训练过程中没有探索性校准。我们通过提出一种新颖的指导探索方法来应对这些挑战，该方法使用差异方向控制器来结合可扩展的探索性动作校正。提供探索性方向的蒙特卡洛评论家合奏作为控制器。提出的方法通过动态改变勘探来改善传统探索方案。然后，我们提出了一种新颖的算法，利用拟议的定向控制器进行政策和评论家修改。所提出的算法在DMControl Suite的各种问题上都优于现代增强算法的现代增强算法。

不确定性量化是现实世界应用中机器学习的主要挑战之一。在强化学习中，一个代理人面对两种不确定性，称为认识论不确定性和态度不确定性。同时解开和评估这些不确定性，有机会提高代理商的最终表现，加速培训并促进部署后的质量保证。在这项工作中，我们为连续控制任务的不确定性感知强化学习算法扩展了深层确定性策略梯度算法（DDPG）。它利用了认识论的不确定性，以加快探索和不确定性来学习风险敏感的政策。我们进行数值实验，表明我们的DDPG变体在机器人控制和功率网络优化方面的基准任务中均优于香草DDPG而没有不确定性估计。

尽管政策梯度方法的普及日益越来越大，但它们尚未广泛用于样品稀缺应用，例如机器人。通过充分利用可用信息，可以提高样本效率。作为强化学习中的关键部件，奖励功能通常仔细设计以引导代理商。因此，奖励功能通常是已知的，允许访问不仅可以访问标量奖励信号，而且允许奖励梯度。为了从奖励梯度中受益，之前的作品需要了解环境动态，这很难获得。在这项工作中，我们开发\ Textit {奖励政策梯度}估计器，这是一种新的方法，可以在不学习模型的情况下整合奖励梯度。绕过模型动态允许我们的估算器实现更好的偏差差异，这导致更高的样本效率，如经验分析所示。我们的方法还提高了在不同的Mujoco控制任务上的近端策略优化的性能。

In contrast to the control-theoretic methods, the lack of stability guarantee remains a significant problem for model-free reinforcement learning (RL) methods. Jointly learning a policy and a Lyapunov function has recently become a promising approach to ensuring the whole system with a stability guarantee. However, the classical Lyapunov constraints researchers introduced cannot stabilize the system during the sampling-based optimization. Therefore, we propose the Adaptive Stability Certification (ASC), making the system reach sampling-based stability. Because the ASC condition can search for the optimal policy heuristically, we design the Adaptive Lyapunov-based Actor-Critic (ALAC) algorithm based on the ASC condition. Meanwhile, our algorithm avoids the optimization problem that a variety of constraints are coupled into the objective in current approaches. When evaluated on ten robotic tasks, our method achieves lower accumulated cost and fewer stability constraint violations than previous studies.

资产分配（或投资组合管理）是确定如何最佳将有限预算的资金分配给一系列金融工具/资产（例如股票）的任务。这项研究调查了使用无模型的深RL代理应用于投资组合管理的增强学习（RL）的性能。我们培训了几个RL代理商的现实股票价格，以学习如何执行资产分配。我们比较了这些RL剂与某些基线剂的性能。我们还比较了RL代理，以了解哪些类别的代理表现更好。从我们的分析中，RL代理可以执行投资组合管理的任务，因为它们的表现明显优于基线代理（随机分配和均匀分配）。四个RL代理（A2C，SAC，PPO和TRPO）总体上优于最佳基线MPT。这显示了RL代理商发现更有利可图的交易策略的能力。此外，基于价值和基于策略的RL代理之间没有显着的性能差异。演员批评者的表现比其他类型的药物更好。同样，在政策代理商方面的表现要好，因为它们在政策评估方面更好，样品效率在投资组合管理中并不是一个重大问题。这项研究表明，RL代理可以大大改善资产分配，因为它们的表现优于强基础。基于我们的分析，在政策上，参与者批评的RL药物显示出最大的希望。

近年来近年来，加固学习方法已经发展了一系列政策梯度方法，主要用于建模随机政策的高斯分布。然而，高斯分布具有无限的支持，而现实世界应用通常具有有限的动作空间。如果它提供有限支持，则该解剖会导致可以消除的估计偏差，因为它提出了有限的支持。在这项工作中，我们调查如何在Openai健身房的两个连续控制任务中训练该测试策略在训练时执行该测试策略。对于这两个任务来说，测试政策在代理人的最终预期奖励方面优于高斯政策，也显示出更多的稳定性和更快的培训过程融合。对于具有高维图像输入的卡路里环境，在高斯政策中，代理的成功率提高了63％。

We present MEM: Multi-view Exploration Maximization for tackling complex visual control tasks. To the best of our knowledge, MEM is the first approach that combines multi-view representation learning and intrinsic reward-driven exploration in reinforcement learning (RL). More specifically, MEM first extracts the specific and shared information of multi-view observations to form high-quality features before performing RL on the learned features, enabling the agent to fully comprehend the environment and yield better actions. Furthermore, MEM transforms the multi-view features into intrinsic rewards based on entropy maximization to encourage exploration. As a result, MEM can significantly promote the sample-efficiency and generalization ability of the RL agent, facilitating solving real-world problems with high-dimensional observations and spare-reward space. We evaluate MEM on various tasks from DeepMind Control Suite and Procgen games. Extensive simulation results demonstrate that MEM can achieve superior performance and outperform the benchmarking schemes with simple architecture and higher efficiency.