We study a multi-agent reinforcement learning (MARL) problem where the agents interact over a given network. The goal of the agents is to cooperatively maximize the average of their entropy-regularized long-term rewards. To overcome the curse of dimensionality and to reduce communication, we propose a Localized Policy Iteration (LPI) algorithm that provably learns a near-globally-optimal policy using only local information. In particular, we show that, despite restricting each agent's attention to only its $\kappa$-hop neighborhood, the agents are able to learn a policy with an optimality gap that decays polynomially in $\kappa$. In addition, we show the finite-sample convergence of LPI to the global optimal policy, which explicitly captures the trade-off between optimality and computational complexity in choosing $\kappa$. Numerical simulations demonstrate the effectiveness of LPI.

This paper introduces a new few-shot learning pipeline that casts relevance ranking for image retrieval as binary ranking relation classification. In comparison to image classification, ranking relation classification is sample efficient and domain agnostic. Besides, it provides a new perspective on few-shot learning and is complementary to state-of-the-art methods. The core component of our deep neural network is a simple MLP, which takes as input an image triplet encoded as the difference between two vector-Kronecker products, and outputs a binary relevance ranking order. The proposed RankMLP can be built on top of any state-of-the-art feature extractors, and our entire deep neural network is called the ranking deep neural network, or RankDNN. Meanwhile, RankDNN can be flexibly fused with other post-processing methods. During the meta test, RankDNN ranks support images according to their similarity with the query samples, and each query sample is assigned the class label of its nearest neighbor. Experiments demonstrate that RankDNN can effectively improve the performance of its baselines based on a variety of backbones and it outperforms previous state-of-the-art algorithms on multiple few-shot learning benchmarks, including miniImageNet, tieredImageNet, Caltech-UCSD Birds, and CIFAR-FS. Furthermore, experiments on the cross-domain challenge demonstrate the superior transferability of RankDNN.The code is available at: https://github.com/guoqianyu-alberta/RankDNN.

基于内部语言模型估计（ILME）语言模型（LM）融合已显示出明显改善的识别结果，而识别域内和跨域语音识别任务的常规浅融合。在本文中，我们试图将ILME方法应用于跨域代码转换语音识别（CSSR）工作。具体而言，我们的好奇心来自几个方面。首先，我们很好奇基于ILME的LM融合对内域和跨域CSSR任务的有效性。我们在不合并两个代码转换域的情况下对此进行验证。更重要的是，我们通过合并两个单语言数据集训练端到端（E2E）语音识别模型，并观察到拟议的基于ILME的LM Fusion对CSSR的功效。来自东南亚和另一个中国大陆CS数据集的SEAME的实验结果证明了拟议的基于ILME的LM融合方法的有效性。

尽管深入学习算法已被深入开发用于计算机辅助结核病诊断（CTD），但它们主要依赖于精心注释的数据集，从而导致了大量时间和资源消耗。弱监督的学习（WSL）利用粗粒标签来完成精细的任务，具有解决此问题的潜力。在本文中，我们首先提出了一个新的大规模结核病（TB）胸部X射线数据集，即结核病胸部X射线属性数据集（TBX-ATT），然后建立一个属性辅助的弱点监督的框架来分类并通过利用属性信息来克服WSL方案中的监督不足来定位结核病。具体而言，首先，TBX-ATT数据集包含2000个X射线图像，其中具有七种用于TB关系推理的属性，这些属性由经验丰富的放射科医生注释。它还包括带有11200 X射线图像的公共TBX11K数据集，以促进弱监督检测。其次，我们利用一个多尺度特征交互模型，用于TB区域分类和属性关系推理检测。在TBX-ATT数据集上评估了所提出的模型，并将作为未来研究的稳固基准。代码和数据将在https://github.com/gangmingzhao/tb-attribute-weak-localization上获得。

Explaining machine learning models is an important and increasingly popular area of research interest. The Shapley value from game theory has been proposed as a prime approach to compute feature importance towards model predictions on images, text, tabular data, and recently graph neural networks (GNNs) on graphs. In this work, we revisit the appropriateness of the Shapley value for GNN explanation, where the task is to identify the most important subgraph and constituent nodes for GNN predictions. We claim that the Shapley value is a non-ideal choice for graph data because it is by definition not structure-aware. We propose a Graph Structure-aware eXplanation (GStarX) method to leverage the critical graph structure information to improve the explanation. Specifically, we define a scoring function based on a new structure-aware value from the cooperative game theory proposed by Hamiache and Navarro (HN). When used to score node importance, the HN value utilizes graph structures to attribute cooperation surplus between neighbor nodes, resembling message passing in GNNs, so that node importance scores reflect not only the node feature importance, but also the node structural roles. We demonstrate that GStarX produces qualitatively more intuitive explanations, and quantitatively improves explanation fidelity over strong baselines on chemical graph property prediction and text graph sentiment classification.

数字医学图像的机器学习和流行的最新进展已经开辟了通过使用深卷积神经网络来解决挑战性脑肿瘤细分（BTS）任务的机会。然而，与非常广泛的RGB图像数据不同，在脑肿瘤分割中使用的医学图像数据在数据刻度方面相对稀缺，但在模态属性方面包含更丰富的信息。为此，本文提出了一种新的跨模型深度学习框架，用于从多种方式MRI数据分段脑肿瘤。核心思想是通过多模态数据挖掘丰富的模式以弥补数据量表不足。所提出的跨型号深度学习框架包括两个学习过程：跨模型特征转换（CMFT）过程和跨模型特征融合（CMFF）过程，其目的是通过跨越不同模态的知识来学习丰富的特征表示数据和融合知识分别来自不同的模态数据。在Brats基准上进行了综合实验，表明，与基线方法和最先进的方法相比，所提出的跨模型深度学习框架可以有效地提高大脑肿瘤分割性能。

数据采集​​和注释中的困难基本上限制了3D医学成像应用的训练数据集的样本尺寸。结果，在没有足够的预训练参数的情况下，构建来自划痕的高性能3D卷积神经网络仍然是一项艰巨的任务。以前关于3D预培训的努力经常依赖于自我监督的方法，它在未标记的数据上使用预测或对比学习来构建不变的3D表示。然而，由于大规模监督信息的不可用，从这些学习框架获得语义不变和歧视性表示仍然存在问题。在本文中，我们重新审视了一种创新但简单的完全监督的3D网络预训练框架，以利用来自大型2D自然图像数据集的语义监督。通过重新设计的3D网络架构，重新设计的自然图像用于解决数据稀缺问题并开发强大的3D表示。四个基准数据集上的综合实验表明，所提出的预先接受的模型可以有效地加速收敛，同时还提高了各种3D医学成像任务，例如分类，分割和检测的准确性。此外，与从头划伤的训练相比，它可以节省高达60％的注释工作。在NIH Deeplesion数据集上，它同样地实现了最先进的检测性能，优于早期的自我监督和完全监督的预训练方法，以及从头训练进行培训的方法。为了促进3D医疗模型的进一步发展，我们的代码和预先接受的模型权重在https://github.com/urmagicsmine/cspr上公开使用。

预训练为深入学习支持的X线射线分析中最近的成功奠定了基础。它通过在源域上进行大规模完全监督或自我监督的学习来学习可转移的图像表示。然而，监督的预培训需要复杂和劳动密集的两级人类辅助注释过程，而自我监督的学习不能与监督范例竞争。为了解决这些问题，我们提出了一个跨监督的方法，命名为审查监督（指的）的自由文本报告，该报告从射线照相中获取来自原始放射学报告的自由监督信号。该方法采用了视觉变压器，旨在从每个患者研究中的多种视图中学习联合表示。在极其有限的监督下，引用其在4个众所周知的X射线数据集上的转移学习和自我监督学习对应。此外，甚至是基于具有人辅助结构标签的射线照相的源区的甚至超越方法。因此，有可能取代规范的预训练方法。

目前的视觉问题应答（VQA）任务主要考虑回答自然图像的人为注释问题。然而，除了自然图像之外，在视觉理解和推理研究中仍然可以解读具有语义丰富性的抽象图。在这项工作中，我们介绍了ICON问题的新挑战（ICONQA），其目标是在图标图像上下文中回答问题。我们发布了ICONQA，这是一个由107,439个问题和三个子任务组成的大型数据集：多图像选择，多文本选择和填充空白。 ICONQA数据集是由真实世界图中的启发，突出了抽象图理解和综合认知推理的重要性。因此，ICONQA不仅需要对象识别和文本理解等感知技能，而且还需要多种认知推理技能，例如几何推理，致辞推理和算术推理。为了促进潜在的iconqa模型来学习图标图像的语义表示，我们进一步发布了一个图标数据集图标645，其中包含377级上的645,687个彩色图标。我们进行广泛的用户研究和盲目实验，并重现各种先进的VQA方法来基准iconQA任务。此外，我们开发了一个强大的ICONQA基线Patch-TRM，它应用金字塔跨模型变压器，其中包含在图标数据集上预先培训的输入图嵌入式。 iconqa和图标645可在https://iconqa.github.io提供。

Unsupervised domain adaptation (UDA) for semantic segmentation is a promising task freeing people from heavy annotation work. However, domain discrepancies in low-level image statistics and high-level contexts compromise the segmentation performance over the target domain. A key idea to tackle this problem is to perform both image-level and feature-level adaptation jointly. Unfortunately, there is a lack of such unified approaches for UDA tasks in the existing literature. This paper proposes a novel UDA pipeline for semantic segmentation that unifies image-level and feature-level adaptation. Concretely, for image-level domain shifts, we propose a global photometric alignment module and a global texture alignment module that align images in the source and target domains in terms of image-level properties. For feature-level domain shifts, we perform global manifold alignment by projecting pixel features from both domains onto the feature manifold of the source domain; and we further regularize category centers in the source domain through a category-oriented triplet loss and perform target domain consistency regularization over augmented target domain images. Experimental results demonstrate that our pipeline significantly outperforms previous methods. In the commonly tested GTA5$\rightarrow$Cityscapes task, our proposed method using Deeplab V3+ as the backbone surpasses previous SOTA by 8%, achieving 58.2% in mIoU.