DeepMind的游戏理论与多代理团队研究多学科学习的几个方面，从计算近似值到游戏理论中的基本概念，再到在富裕的空间环境中模拟社会困境，并在困难的团队协调任务中培训3-D类人动物。我们小组的一个签名目的是使用DeepMind在DeepMind中提供的资源和专业知识，以深入强化学习来探索复杂环境中的多代理系统，并使用这些基准来提高我们的理解。在这里，我们总结了我们团队的最新工作，并提出了一种分类法，我们认为这重点介绍了多代理研究中许多重要的开放挑战。

大图通常出现在社交网络，知识图，推荐系统，生命科学和决策问题中。通过其高级别属性总结大图有助于解决这些设置中的问题。在光谱聚类中，我们旨在确定大多数边缘落在簇内的节点簇，而在簇之间只有很少的边缘。此任务对于许多下游应用和探索性分析很重要。光谱聚类的核心步骤是执行相应图的拉普拉斯矩阵（或等效地，奇异值分解，SVD）的特征分类。迭代奇异值分解方法的收敛取决于给定矩阵的光谱的特征，即连续特征值之间的差异。对于对应于群集图的图形的图形拉普拉斯，特征值将是非负的，但很小（小于$ 1 $）的减慢收敛性。本文引入了一种可行的方法，用于扩张光谱以加速SVD求解器，然后又是光谱群集。这是通过对矩阵操作的多项式近似来实现的，矩阵操作有利地改变矩阵的光谱而不更改其特征向量。实验表明，这种方法显着加速了收敛，我们解释了如何并行化和随机近似于可用的计算。

研究多层合作研究中的一个关键挑战是不仅需要有效合作的个人代理，而且需要与谁合作。当其他代理人隐藏的情况下，可能是错误的动机和目标时，这在局势中特别关键。社交扣除游戏提供途径来研究个人如何学习如何综合有关其他人的潜在不可靠的信息，并阐明其真正的动机。在这项工作中，我们展示了隐藏的议程，这是一个双队的社交扣除游戏，为在未知团队对齐的情况下学习学习代理的2D环境。环境承认两支球队的丰富战略。在隐藏议程中培训的强化学习代理表明，代理商可以学习各种行为，包括合作和投票，而无需以自然语言沟通。

与人类合作需要迅速适应他们的个人优势，缺点和偏好。遗憾的是，大多数标准的多智能经纪增强学习技术，如自助（SP）或人口剧（PP），产生培训合作伙伴的代理商，并且对人类不完全概括。或者，研究人员可以使用行为克隆收集人体数据，培训人类模型，然后使用该模型培训“人类感知”代理（“行为克隆播放”或BCP）。虽然这种方法可以改善代理商的概括到新的人类共同球员，但它涉及首先收集大量人体数据的繁重和昂贵的步骤。在这里，我们研究如何培训与人类合作伙伴合作的代理的问题，而无需使用人类数据。我们认为这个问题的症结是制作各种培训伙伴。从竞争域中取得成功的多智能经纪人方法绘制灵感，我们发现令人惊讶的简单方法非常有效。我们培养我们的代理商合作伙伴作为对自行发行代理人口的最佳反应及其过去培训的过去检查点，这是我们呼叫虚构共同扮演（FCP）的方法。我们的实验专注于两位运动员协作烹饪模拟器，最近被提议作为与人类协调的挑战问题。我们发现，与新的代理商和人类合作伙伴配对时，FCP代理商会显着高于SP，PP和BCP。此外，人类还报告了强烈的主观偏好，以与所有基线与FCP代理合作。

深度加强学习（RL）的最新进展导致许多2人零和游戏中的相当大的进展，如去，扑克和星际争霸。这种游戏的纯粹对抗性质允许概念上简单地应用R1方法。然而，现实世界的设置是许多代理商，代理交互是复杂的共同利益和竞争方面的混合物。我们认为外交，一个旨在突出由多种代理交互导致的困境的7人棋盘游戏。它还具有大型组合动作空间和同时移动，这对RL算法具有具有挑战性。我们提出了一个简单但有效的近似最佳响应操作员，旨在处理大型组合动作空间并同时移动。我们还介绍了一系列近似虚构游戏的政策迭代方法。通过这些方法，我们成功地将RL申请到外交：我们认为我们的代理商令人信服地令人信服地表明，游戏理论均衡分析表明新过程产生了一致的改进。

Artificial Intelligence (AI) has become commonplace to solve routine everyday tasks. Because of the exponential growth in medical imaging data volume and complexity, the workload on radiologists is steadily increasing. We project that the gap between the number of imaging exams and the number of expert radiologist readers required to cover this increase will continue to expand, consequently introducing a demand for AI-based tools that improve the efficiency with which radiologists can comfortably interpret these exams. AI has been shown to improve efficiency in medical-image generation, processing, and interpretation, and a variety of such AI models have been developed across research labs worldwide. However, very few of these, if any, find their way into routine clinical use, a discrepancy that reflects the divide between AI research and successful AI translation. To address the barrier to clinical deployment, we have formed MONAI Consortium, an open-source community which is building standards for AI deployment in healthcare institutions, and developing tools and infrastructure to facilitate their implementation. This report represents several years of weekly discussions and hands-on problem solving experience by groups of industry experts and clinicians in the MONAI Consortium. We identify barriers between AI-model development in research labs and subsequent clinical deployment and propose solutions. Our report provides guidance on processes which take an imaging AI model from development to clinical implementation in a healthcare institution. We discuss various AI integration points in a clinical Radiology workflow. We also present a taxonomy of Radiology AI use-cases. Through this report, we intend to educate the stakeholders in healthcare and AI (AI researchers, radiologists, imaging informaticists, and regulators) about cross-disciplinary challenges and possible solutions.

Rigorous guarantees about the performance of predictive algorithms are necessary in order to ensure their responsible use. Previous work has largely focused on bounding the expected loss of a predictor, but this is not sufficient in many risk-sensitive applications where the distribution of errors is important. In this work, we propose a flexible framework to produce a family of bounds on quantiles of the loss distribution incurred by a predictor. Our method takes advantage of the order statistics of the observed loss values rather than relying on the sample mean alone. We show that a quantile is an informative way of quantifying predictive performance, and that our framework applies to a variety of quantile-based metrics, each targeting important subsets of the data distribution. We analyze the theoretical properties of our proposed method and demonstrate its ability to rigorously control loss quantiles on several real-world datasets.

The broad usage of mobile devices nowadays, the sensitiveness of the information contained in them, and the shortcomings of current mobile user authentication methods are calling for novel, secure, and unobtrusive solutions to verify the users' identity. In this article, we propose TypeFormer, a novel Transformer architecture to model free-text keystroke dynamics performed on mobile devices for the purpose of user authentication. The proposed model consists in Temporal and Channel Modules enclosing two Long Short-Term Memory (LSTM) recurrent layers, Gaussian Range Encoding (GRE), a multi-head Self-Attention mechanism, and a Block-Recurrent structure. Experimenting on one of the largest public databases to date, the Aalto mobile keystroke database, TypeFormer outperforms current state-of-the-art systems achieving Equal Error Rate (EER) values of 3.25% using only 5 enrolment sessions of 50 keystrokes each. In such way, we contribute to reducing the traditional performance gap of the challenging mobile free-text scenario with respect to its desktop and fixed-text counterparts. Additionally, we analyse the behaviour of the model with different experimental configurations such as the length of the keystroke sequences and the amount of enrolment sessions, showing margin for improvement with more enrolment data. Finally, a cross-database evaluation is carried out, demonstrating the robustness of the features extracted by TypeFormer in comparison with existing approaches.

Analogical proportions compare pairs of items (a, b) and (c, d) in terms of their differences and similarities. They play a key role in the formalization of analogical inference. The paper first discusses how to improve analogical inference in terms of accuracy and in terms of computational cost. Then it indicates the potential of analogical proportions for explanation. Finally, it highlights the close relationship between analogical proportions and multi-valued dependencies, which reveals an unsuspected aspect of the former.

Algorithms that involve both forecasting and optimization are at the core of solutions to many difficult real-world problems, such as in supply chains (inventory optimization), traffic, and in the transition towards carbon-free energy generation in battery/load/production scheduling in sustainable energy systems. Typically, in these scenarios we want to solve an optimization problem that depends on unknown future values, which therefore need to be forecast. As both forecasting and optimization are difficult problems in their own right, relatively few research has been done in this area. This paper presents the findings of the ``IEEE-CIS Technical Challenge on Predict+Optimize for Renewable Energy Scheduling," held in 2021. We present a comparison and evaluation of the seven highest-ranked solutions in the competition, to provide researchers with a benchmark problem and to establish the state of the art for this benchmark, with the aim to foster and facilitate research in this area. The competition used data from the Monash Microgrid, as well as weather data and energy market data. It then focused on two main challenges: forecasting renewable energy production and demand, and obtaining an optimal schedule for the activities (lectures) and on-site batteries that lead to the lowest cost of energy. The most accurate forecasts were obtained by gradient-boosted tree and random forest models, and optimization was mostly performed using mixed integer linear and quadratic programming. The winning method predicted different scenarios and optimized over all scenarios jointly using a sample average approximation method.