In recent years, Monte Carlo tree search (MCTS) has achieved widespread adoption within the game community. Its use in conjunction with deep reinforcement learning has produced success stories in many applications. While these approaches have been implemented in various games, from simple board games to more complicated video games such as StarCraft, the use of deep neural networks requires a substantial training period. In this work, we explore on-line adaptivity in MCTS without requiring pre-training. We present MCTS-TD, an adaptive MCTS algorithm improved with temporal difference learning. We demonstrate our new approach on the game miniXCOM, a simplified version of XCOM, a popular commercial franchise consisting of several turn-based tactical games, and show how adaptivity in MCTS-TD allows for improved performances against opponents.

Monte Carlo Tree Search (MCTS) is a recently proposed search method that combines the precision of tree search with the generality of random sampling. It has received considerable interest due to its spectacular success in the difficult problem of computer Go, but has also proved beneficial in a range of other domains. This paper is a survey of the literature to date, intended to provide a snapshot of the state of the art after the first five years of MCTS research. We outline the core algorithm's derivation, impart some structure on the many variations and enhancements that have been proposed, and summarise the results from the key game and non-game domains to which MCTS methods have been applied. A number of open research questions indicate that the field is ripe for future work.

蒙特卡洛树搜索（MCT）是设计游戏机器人或解决顺序决策问题的强大方法。该方法依赖于平衡探索和开发的智能树搜索。MCT以模拟的形式进行随机抽样，并存储动作的统计数据，以在每个随后的迭代中做出更有教育的选择。然而，该方法已成为组合游戏的最新技术，但是，在更复杂的游戏（例如那些具有较高的分支因素或实时系列的游戏）以及各种实用领域（例如，运输，日程安排或安全性）有效的MCT应用程序通常需要其与问题有关的修改或与其他技术集成。这种特定领域的修改和混合方法是本调查的主要重点。最后一项主要的MCT调查已于2012年发布。自发布以来出现的贡献特别感兴趣。

使用规划算法和神经网络模型的基于模型的强化学习范例最近在不同的应用中实现了前所未有的结果，导致现在被称为深度增强学习的内容。这些代理非常复杂，涉及多个组件，可能会为研究产生挑战的因素。在这项工作中，我们提出了一个适用于这些类型代理的新模块化软件架构，以及一组建筑块，可以轻松重复使用和组装，以构建基于模型的增强学习代理。这些构建块包括规划算法，策略和丢失功能。我们通过将多个这些构建块组合实现和测试经过针对三种不同的测试环境的代理来说明这种架构的使用：Cartpole，Minigrid和Tictactoe。在我们的实施中提供的一个特定的规划算法，并且以前没有用于加强学习，我们称之为Imperage Minimax，在三个测试环境中取得了良好的效果。用这种架构进行的实验表明，规划算法，政策和损失函数的最佳组合依赖性严重问题。该结果提供了证据表明，拟议的架构是模块化和可重复使用的，对想要研究新环境和技术的强化学习研究人员有用。

强化学习最近已成为解决棋盘游戏领域中复杂问题的非常强大的工具，其中通常需要代理来根据其自身的经验和收到的奖励来学习复杂的策略和移动。尽管RL胜过用于玩简单视频游戏和受欢迎的棋盘游戏的现有最新方法，但它尚未证明其在古代游戏中的能力。在这里，我们解决了一个这样的问题，在该问题中，我们使用不同的方法来训练代理商，即蒙特卡洛，Qlearning和Hir Hir Hight Sarsa能够学习最佳政策来发挥战略性的UR皇家游戏。我们游戏的状态空间很复杂，但是我们的代理商在玩游戏和学习重要的战略动作方面表现出令人鼓舞的结果。尽管很难得出结论，当接受有限的资源培训时，算法总体上的表现更好，但预计SARSA在学习最快的学习方面表现出了令人鼓舞的结果。

2048 is a single-player stochastic puzzle game. This intriguing and addictive game has been popular worldwide and has attracted researchers to develop game-playing programs. Due to its simplicity and complexity, 2048 has become an interesting and challenging platform for evaluating the effectiveness of machine learning methods. This dissertation conducts comprehensive research on reinforcement learning and computer game algorithms for 2048. First, this dissertation proposes optimistic temporal difference learning, which significantly improves the quality of learning by employing optimistic initialization to encourage exploration for 2048. Furthermore, based on this approach, a state-of-the-art program for 2048 is developed, which achieves the highest performance among all learning-based programs, namely an average score of 625377 points and a rate of 72% for reaching 32768-tiles. Second, this dissertation investigates several techniques related to 2048, including the n-tuple network ensemble learning, Monte Carlo tree search, and deep reinforcement learning. These techniques are promising for further improving the performance of the current state-of-the-art program. Finally, this dissertation discusses pedagogical applications related to 2048 by proposing course designs and summarizing the teaching experience. The proposed course designs use 2048-like games as materials for beginners to learn reinforcement learning and computer game algorithms. The courses have been successfully applied to graduate-level students and received well by student feedback.

在加强学习的背景下，我们介绍了一个国家的关键性的概念，这表明在该特定状态下采取行动的选择程度影响预期的回报。也就是说，采取行动的选择更容易影响最终结果的状态被认为比它不太可能影响最终结果的国家更为重要。我们制定了基于临界的不同步骤编号算法（CVS） - 一种灵活的步骤编号算法，其利用人类提供的临界功能，或直接从环境中学到。我们在包括Atari Pong环境，道路树环境和射击环境的三个不同领域中测试它。我们展示了CVS能够优于流行的学习算法，如深Q-Learning和Monte Carlo。

本文涵盖了基于N组的加强学习（RL）算法。我们为TD-，Sarsa-and Q-Learning提供了新的算法，这些算法在各种游戏中无缝工作，任意数量的玩家。这是通过采用以球员为中心的视图来实现的，其中每个玩家将他/她的奖励传播到以前的轮次。我们将称为最终适应RL（Farl）的新元素添加到所有这些算法。我们的主要贡献是，Farl是一项最重要的成分，可以在各种游戏中以可爱的球员为中心的观点实现成功。我们向七个棋盘游戏报告结果1,2和3名球员，包括奥赛罗，Connectfour和Hex。在大多数情况下，发现Farl非常重要，无法学习近乎完美的竞争策略。所有算法都在GitHub上的GBG框架中提供。

传统的增强学习（RL）环境通常在培训和测试阶段都相同。因此，当前的RL方法在很大程度上不能推广到概念上相似但与已训练的方法不同的测试环境，我们将其称为新型测试环境。为了将RL研究推向可以推广到新的测试环境的算法，我们介绍了砖Tic-TAC-TOE（BTTT）测试床，其中在测试环境中的砖位与训练环境中的砖位不同。使用BTTT环境上的圆形锦标赛，我们表明传统的RL国家搜索方法，例如Monte Carlo Tree Search（MCTS）和Minimax，比Alphazero更广泛地对新型测试环境更具概括性。令人惊讶的是，Alphazero已被证明可以在GO，Chess和Shogi等环境中实现超人的性能，这可能会导致人们认为它在新颖的测试环境中的性能很好。我们的结果表明，BTTT虽然很简单，但足够丰富，可以探索Alphazero的普遍性。我们发现，仅增加MCT的lookahead迭代是不足以使Alphazero推广到一些新型的测试环境。相反，增加各种培训环境有助于逐步改善所有可能的起始砖配置中的普遍性。

最近，开创性算法Alphago和Alphazero在游戏学习和深入的强化学习方面开始了一个新时代。尽管Alphago和Alphazero的成就 - 在超级人类层面上玩的GO和其他复杂游戏 - 确实令人印象深刻，但这些架构的缺点是它们需要高度的计算资源。许多研究人员正在寻找类似于alphazero但计算需求较低的方法，因此更容易重现。在本文中，我们选择了Alphazero的重要元素 - 蒙特卡洛树搜索（MCTS）计划阶段 - 并将其与时间差异（TD）学习剂相结合。我们首次将MCT包裹在TD N培训网络上，我们仅在测试时间使用此包装来创建多功能代理，从而使计算需求保持较低。我们将这种新体系结构应用于多个复杂游戏（Othello，Connectfour，Rubik的Cube），并显示了这种受alphazero启发的MCTS包装器所获得的优势。特别是，我们提出的结果是，该代理是第一个在标准硬件（无GPU或TPU）上训练的代理商，击败非常强大的Othello计划EDAX到包括7级（大多数其他学习中的学习中，从而只能失败EDAX至2级）。

在这项工作中，我们提出了一种初步调查一种名为DYNA-T的新算法。在钢筋学习（RL）中，规划代理有自己的环境表示作为模型。要发现与环境互动的最佳政策，代理商会收集试验和错误时尚的经验。经验可用于学习更好的模型或直接改进价值函数和政策。通常是分离的，Dyna-Q是一种混合方法，在每次迭代，利用真实体验更新模型以及值函数，同时使用模拟数据从其模型中的应用程序进行行动。然而，规划过程是计算昂贵的并且强烈取决于国家行动空间的维度。我们建议在模拟体验上构建一个上置信树（UCT），并在在线学习过程中搜索要选择的最佳动作。我们证明了我们提出的方法对来自Open AI的三个测试平台环境的一系列初步测试的有效性。与Dyna-Q相比，Dyna-T通过选择更强大的动作选择策略来优于随机环境中的最先进的RL代理。

除了独奏游戏外，棋盘游戏至少需要其他玩家才能玩。因此，当对手失踪时，我们创建了人工智能（AI）代理商来对抗我们。这些AI代理是通过多种方式创建的，但是这些代理的一个挑战是，与我们相比，代理可以具有较高的能力。在这项工作中，我们描述了如何创建玩棋盘游戏的较弱的AI代理。我们使用Tic-Tac-toe，九名成员的莫里斯和曼卡拉，我们的技术使用了增强学习模型，代理商使用Q学习算法来学习这些游戏。我们展示了这些代理商如何学会完美地玩棋盘游戏，然后我们描述了制作这些代理商较弱版本的方法。最后，我们提供了比较AI代理的方法。

This paper surveys the eld of reinforcement learning from a computer-science perspective. It is written to be accessible to researchers familiar with machine learning. Both the historical basis of the eld and a broad selection of current work are summarized. Reinforcement learning is the problem faced by an agent that learns behavior through trial-and-error interactions with a dynamic environment. The work described here has a resemblance to work in psychology, but di ers considerably in the details and in the use of the word \reinforcement." The paper discusses central issues of reinforcement learning, including trading o exploration and exploitation, establishing the foundations of the eld via Markov decision theory, learning from delayed reinforcement, constructing empirical models to accelerate learning, making use of generalization and hierarchy, and coping with hidden state. It concludes with a survey of some implemented systems and an assessment of the practical utility of current methods for reinforcement learning.

Deep reinforcement learning is poised to revolutionise the field of AI and represents a step towards building autonomous systems with a higher level understanding of the visual world. Currently, deep learning is enabling reinforcement learning to scale to problems that were previously intractable, such as learning to play video games directly from pixels. Deep reinforcement learning algorithms are also applied to robotics, allowing control policies for robots to be learned directly from camera inputs in the real world. In this survey, we begin with an introduction to the general field of reinforcement learning, then progress to the main streams of value-based and policybased methods. Our survey will cover central algorithms in deep reinforcement learning, including the deep Q-network, trust region policy optimisation, and asynchronous advantage actor-critic. In parallel, we highlight the unique advantages of deep neural networks, focusing on visual understanding via reinforcement learning. To conclude, we describe several current areas of research within the field.

随着alphago的突破，人机游戏的AI已经成为一个非常热门的话题，吸引了世界各地的研究人员，这通常是测试人工智能的有效标准。已经开发了各种游戏AI系统（AIS），如Plibratus，Openai Five和AlphaStar，击败了专业人员。在本文中，我们调查了最近的成功游戏AIS，覆盖棋盘游戏AIS，纸牌游戏AIS，第一人称射击游戏AIS和实时战略游戏AIS。通过这项调查，我们1）比较智能决策领域的不同类型游戏之间的主要困难; 2）说明了开发专业水平AIS的主流框架和技术; 3）提高当前AIS中的挑战或缺点，以实现智能决策; 4）试图提出奥运会和智能决策技巧的未来趋势。最后，我们希望这篇简短的审查可以为初学者提供介绍，激发了在游戏中AI提交的研究人员的见解。

We present the first deep learning model to successfully learn control policies directly from high-dimensional sensory input using reinforcement learning. The model is a convolutional neural network, trained with a variant of Q-learning, whose input is raw pixels and whose output is a value function estimating future rewards. We apply our method to seven Atari 2600 games from the Arcade Learning Environment, with no adjustment of the architecture or learning algorithm. We find that it outperforms all previous approaches on six of the games and surpasses a human expert on three of them.

游戏历史悠久的历史悠久地作为人工智能进步的基准。最近，使用搜索和学习的方法在一系列完美的信息游戏中表现出强烈的表现，并且使用游戏理论推理和学习的方法对特定的不完美信息扑克变体表示了很强的性能。我们介绍游戏玩家，一个通用算法，统一以前的方法，结合导游搜索，自助学习和游戏理论推理。游戏播放器是实现大型完美和不完美信息游戏中强大实证性能的第一个算法 - 这是一项真正的任意环境算法的重要一步。我们证明了游戏玩家是声音，融合到完美的游戏，因为可用的计算时间和近似容量增加。游戏播放器在国际象棋上达到了强大的表现，然后击败了最强大的公开可用的代理商，在头上没有限制德克萨斯州扑克（Slumbot），击败了苏格兰院子的最先进的代理人，这是一个不完美的信息游戏，说明了引导搜索，学习和游戏理论推理的价值。

In fighting games, individual players of the same skill level often exhibit distinct strategies from one another through their gameplay. Despite this, the majority of AI agents for fighting games have only a single strategy for each "level" of difficulty. To make AI opponents more human-like, we'd ideally like to see multiple different strategies at each level of difficulty, a concept we refer to as "multidimensional" difficulty. In this paper, we introduce a diversity-based deep reinforcement learning approach for generating a set of agents of similar difficulty that utilize diverse strategies. We find this approach outperforms a baseline trained with specialized, human-authored reward functions in both diversity and performance.

Constructing agents with planning capabilities has long been one of the main challenges in the pursuit of artificial intelligence. Tree-based planning methods have enjoyed huge success in challenging domains, such as chess and Go, where a perfect simulator is available. However, in real-world problems the dynamics governing the environment are often complex and unknown. In this work we present the MuZero algorithm which, by combining a tree-based search with a learned model, achieves superhuman performance in a range of challenging and visually complex domains, without any knowledge of their underlying dynamics. MuZero learns a model that, when applied iteratively, predicts the quantities most directly relevant to planning: the reward, the action-selection policy, and the value function. When evaluated on 57 different Atari games -the canonical video game environment for testing AI techniques, in which model-based planning approaches have historically struggled -our new algorithm achieved a new state of the art. When evaluated on Go, chess and shogi, without any knowledge of the game rules, MuZero matched the superhuman performance of the AlphaZero algorithm that was supplied with the game rules.

In this article we introduce the Arcade Learning Environment (ALE): both a challenge problem and a platform and methodology for evaluating the development of general, domain-independent AI technology. ALE provides an interface to hundreds of Atari 2600 game environments, each one different, interesting, and designed to be a challenge for human players. ALE presents significant research challenges for reinforcement learning, model learning, model-based planning, imitation learning, transfer learning, and intrinsic motivation. Most importantly, it provides a rigorous testbed for evaluating and comparing approaches to these problems. We illustrate the promise of ALE by developing and benchmarking domain-independent agents designed using well-established AI techniques for both reinforcement learning and planning. In doing so, we also propose an evaluation methodology made possible by ALE, reporting empirical results on over 55 different games. All of the software, including the benchmark agents, is publicly available.