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。

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.

Traditionally, data analysis and theory have been viewed as separate disciplines, each feeding into fundamentally different types of models. Modern deep learning technology is beginning to unify these two disciplines and will produce a new class of predictively powerful space weather models that combine the physical insights gained by data and theory. We call on NASA to invest in the research and infrastructure necessary for the heliophysics' community to take advantage of these advances.

Non-invasive prostate cancer detection from MRI has the potential to revolutionize patient care by providing early detection of clinically-significant disease (ISUP grade group >= 2), but has thus far shown limited positive predictive value. To address this, we present an MRI-based deep learning method for predicting clinically significant prostate cancer applicable to a patient population with subsequent ground truth biopsy results ranging from benign pathology to ISUP grade group~5. Specifically, we demonstrate that mixed supervision via diverse histopathological ground truth improves classification performance despite the cost of reduced concordance with image-based segmentation. That is, where prior approaches have utilized pathology results as ground truth derived from targeted biopsies and whole-mount prostatectomy to strongly supervise the localization of clinically significant cancer, our approach also utilizes weak supervision signals extracted from nontargeted systematic biopsies with regional localization to improve overall performance. Our key innovation is performing regression by distribution rather than simply by value, enabling use of additional pathology findings traditionally ignored by deep learning strategies. We evaluated our model on a dataset of 973 (testing n=160) multi-parametric prostate MRI exams collected at UCSF from 2015-2018 followed by MRI/ultrasound fusion (targeted) biopsy and systematic (nontargeted) biopsy of the prostate gland, demonstrating that deep networks trained with mixed supervision of histopathology can significantly exceed the performance of the Prostate Imaging-Reporting and Data System (PI-RADS) clinical standard for prostate MRI interpretation.

In a recent paper Wunderlich and Pehle introduced the EventProp algorithm that enables training spiking neural networks by gradient descent on exact gradients. In this paper we present extensions of EventProp to support a wider class of loss functions and an implementation in the GPU enhanced neuronal networks framework which exploits sparsity. The GPU acceleration allows us to test EventProp extensively on more challenging learning benchmarks. We find that EventProp performs well on some tasks but for others there are issues where learning is slow or fails entirely. Here, we analyse these issues in detail and discover that they relate to the use of the exact gradient of the loss function, which by its nature does not provide information about loss changes due to spike creation or spike deletion. Depending on the details of the task and loss function, descending the exact gradient with EventProp can lead to the deletion of important spikes and so to an inadvertent increase of the loss and decrease of classification accuracy and hence a failure to learn. In other situations the lack of knowledge about the benefits of creating additional spikes can lead to a lack of gradient flow into earlier layers, slowing down learning. We eventually present a first glimpse of a solution to these problems in the form of `loss shaping', where we introduce a suitable weighting function into an integral loss to increase gradient flow from the output layer towards earlier layers.

Three-dimensional (3D) freehand ultrasound (US) reconstruction without a tracker can be advantageous over its two-dimensional or tracked counterparts in many clinical applications. In this paper, we propose to estimate 3D spatial transformation between US frames from both past and future 2D images, using feed-forward and recurrent neural networks (RNNs). With the temporally available frames, a further multi-task learning algorithm is proposed to utilise a large number of auxiliary transformation-predicting tasks between them. Using more than 40,000 US frames acquired from 228 scans on 38 forearms of 19 volunteers in a volunteer study, the hold-out test performance is quantified by frame prediction accuracy, volume reconstruction overlap, accumulated tracking error and final drift, based on ground-truth from an optical tracker. The results show the importance of modelling the temporal-spatially correlated input frames as well as output transformations, with further improvement owing to additional past and/or future frames. The best performing model was associated with predicting transformation between moderately-spaced frames, with an interval of less than ten frames at 20 frames per second (fps). Little benefit was observed by adding frames more than one second away from the predicted transformation, with or without LSTM-based RNNs. Interestingly, with the proposed approach, explicit within-sequence loss that encourages consistency in composing transformations or minimises accumulated error may no longer be required. The implementation code and volunteer data will be made publicly available ensuring reproducibility and further research.

解释视觉场景的含义不仅需要识别其成分对象，还需要对象相互关系的丰富语义表征。在这里，我们通过将现代计算技术应用于复杂自然场景引起的人类脑反应的大规模7T fMRI数据集，研究视觉语义转换的神经机制。使用通过将语言深度学习模型应用于人类生成的场景描述获得的语义嵌入，我们确定了编码语义场景描述的大脑区域的广泛分布网络。重要的是，这些语义嵌入比传统对象类别标签更好地解释了这些区域的活动。此外，尽管参与者没有积极从事语义任务，但它们还是活动的有效预测指标，这表明Visuo-Semantic转换是默认的视觉方式。为了支持这种观点，我们表明，可以直接通过大脑活动模式直接将场景字幕的高度精确重建。最后，经过语义嵌入训练的经常性卷积神经网络进一步超过了语义嵌入在预测大脑活动时的语义嵌入，从而提供了大脑视觉语义转换的机械模型。这些实验和计算结果在一起表明，将视觉输入转换为丰富的语义场景描述可能是视觉系统的核心目标，并且将重点放在这一新目标上可能会导致改进人类大脑中视觉信息处理的模型。

成像检查（例如胸部X射线照相）将产生一小部分常见发现和一组少数罕见的发现。虽然训练有素的放射科医生可以通过研究一些代表性的例子来学习罕见条件的视觉呈现，但是教机器从这种“长尾”分布中学习的情况更加困难，因为标准方法很容易偏向最常见的类别。在本文中，我们介绍了胸部X射线胸腔疾病特定领域的长尾学习问题的全面基准研究。我们专注于从自然分布的胸部X射线数据中学习，不仅优化了分类精度，不仅是常见的“头”类，而且还优化了罕见但至关重要的“尾巴”类。为此，我们引入了一个具有挑战性的新长尾X射线基准，以促进开发长尾学习方法进行医学图像分类。该基准由两个用于19-和20向胸部疾病分类的胸部X射线数据集组成，其中包含多达53,000的类别，只有7个标记的训练图像。我们在这种新的基准上评估了标准和最先进的长尾学习方法，分析这些方法的哪些方面对长尾医学图像分类最有益，并总结了对未来算法设计的见解。数据集，训练有素的模型和代码可在https://github.com/vita-group/longtailcxr上找到。

增强现实（AR）游戏是一个丰富的环境，用于研究和测试提供微妙的用户指导和培训的计算系统。在特定的计算机系统中，旨在增强用户状况意识的计算机系统受益于AR耳机中可用的传感器和计算功率。在这篇正在进行的论文中，我们提出了一个新的环境，以研究情况意识和注意力指导（SAAG）：棋盘游戏Carcassonne的增强现实版本。我们还介绍了生产SAAG管道的最初工作，包括创建游戏状态编码，游戏玩法AI的开发和培训以及情况建模和凝视跟踪系统的设计。

大气效应（例如湍流和背景热噪声）抑制了在开关键控自由空间光学通信中使用的相干光的传播。在这里，我们介绍并实验验证了卷积神经网络，以降低后处理中自由空间光学通信的位错误率，而自由空间光学通信的位比基于高级光学器件的现有解决方案明显简单，更便宜。我们的方法由两个神经网络组成，这是第一个确定在热噪声和湍流中存在相干位序列以及第二个解调相干位序列的存在。通过生成连贯的光线，将它们与热灯结合在一起，并通过湍流的水箱将其结合起来，通过生成开关的键入键流，可以通过实验获得我们网络的所有数据，从而获得了模拟的湍流，并将其传递给了最终的光线。高度准确性。我们的卷积神经网络提高了与阈值分类方案相比的检测准确性，并具有与当前解调和误差校正方案集成的能力。