Nowadays, fake news easily propagates through online social networks and becomes a grand threat to individuals and society. Assessing the authenticity of news is challenging due to its elaborately fabricated contents, making it difficult to obtain large-scale annotations for fake news data. Due to such data scarcity issues, detecting fake news tends to fail and overfit in the supervised setting. Recently, graph neural networks (GNNs) have been adopted to leverage the richer relational information among both labeled and unlabeled instances. Despite their promising results, they are inherently focused on pairwise relations between news, which can limit the expressive power for capturing fake news that spreads in a group-level. For example, detecting fake news can be more effective when we better understand relations between news pieces shared among susceptible users. To address those issues, we propose to leverage a hypergraph to represent group-wise interaction among news, while focusing on important news relations with its dual-level attention mechanism. Experiments based on two benchmark datasets show that our approach yields remarkable performance and maintains the high performance even with a small subset of labeled news data.

The number of international benchmarking competitions is steadily increasing in various fields of machine learning (ML) research and practice. So far, however, little is known about the common practice as well as bottlenecks faced by the community in tackling the research questions posed. To shed light on the status quo of algorithm development in the specific field of biomedical imaging analysis, we designed an international survey that was issued to all participants of challenges conducted in conjunction with the IEEE ISBI 2021 and MICCAI 2021 conferences (80 competitions in total). The survey covered participants' expertise and working environments, their chosen strategies, as well as algorithm characteristics. A median of 72% challenge participants took part in the survey. According to our results, knowledge exchange was the primary incentive (70%) for participation, while the reception of prize money played only a minor role (16%). While a median of 80 working hours was spent on method development, a large portion of participants stated that they did not have enough time for method development (32%). 25% perceived the infrastructure to be a bottleneck. Overall, 94% of all solutions were deep learning-based. Of these, 84% were based on standard architectures. 43% of the respondents reported that the data samples (e.g., images) were too large to be processed at once. This was most commonly addressed by patch-based training (69%), downsampling (37%), and solving 3D analysis tasks as a series of 2D tasks. K-fold cross-validation on the training set was performed by only 37% of the participants and only 50% of the participants performed ensembling based on multiple identical models (61%) or heterogeneous models (39%). 48% of the respondents applied postprocessing steps.

Machine learning algorithms typically assume that the training and test samples come from the same distributions, i.e., in-distribution. However, in open-world scenarios, streaming big data can be Out-Of-Distribution (OOD), rendering these algorithms ineffective. Prior solutions to the OOD challenge seek to identify invariant features across different training domains. The underlying assumption is that these invariant features should also work reasonably well in the unlabeled target domain. By contrast, this work is interested in the domain-specific features that include both invariant features and features unique to the target domain. We propose a simple yet effective approach that relies on correlations in general regardless of whether the features are invariant or not. Our approach uses the most confidently predicted samples identified by an OOD base model (teacher model) to train a new model (student model) that effectively adapts to the target domain. Empirical evaluations on benchmark datasets show that the performance is improved over the SOTA by ~10-20%

词汇嵌入在很大程度上仅限于个人和独立的社会类别。但是，现实世界中的语料库通常提出可能相互关联或相交的多个社会类别。例如，“头发编织”与非洲裔美国女性刻板印象相关，但非洲裔美国人也不是女性。因此，这项工作研究与多个社会类别相关的偏见：由不同类别和交叉偏见的联合引起的联合偏见，这些偏见与组成类别的偏见不重叠。我们首先从经验上观察到，单个偏见是非琐事相交的（即在一维子空间上）。从社会科学和语言理论中的交叉理论中，我们使用单个偏见的非线性几何形状为多个社会类别构建了一个交叉子空间。经验评估证实了我们方法的功效。数据和实现代码可以在https://github.com/githublucheng/implementation-of-josec-coling-22下载。

磁共振图像（MRI）中的脑肿瘤分割（BTS）对于脑肿瘤诊断，癌症管理和研究目的至关重要。随着十年小型挑战的巨大成功以及CNN和Transformer算法的进步，已经提出了许多出色的BTS模型来解决BTS在不同技术方面的困难。但是，现有研究几乎没有考虑如何以合理的方式融合多模式图像。在本文中，我们利用了放射科医生如何从多种MRI模态诊断脑肿瘤的临床知识，并提出了一种称为CKD-TRANSBTS的临床知识驱动的脑肿瘤分割模型。我们没有直接串联所有模式，而是通过根据MRI的成像原理将输入方式分为两组来重新组织输入方式。具有拟议模态相关的跨意义块（MCCA）的双支支混合式编码器旨在提取多模式图像特征。所提出的模型以局部特征表示能力的能力来继承来自变压器和CNN的强度，以提供精确的病变边界和3D体积图像的远程特征提取。为了弥合变压器和CNN功能之间的间隙，我们提出了解码器中的反式和CNN功能校准块（TCFC）。我们将提出的模型与五个基于CNN的模型和六个基于Transformer的模型在Brats 2021挑战数据集上进行了比较。广泛的实验表明，与所有竞争对手相比，所提出的模型可实现最先进的脑肿瘤分割性能。

盲级超分辨率（SR）旨在从低分辨率（LR）图像中恢复高质量的视觉纹理，通常通过下采样模糊内核和添加剂噪声来降解。由于现实世界中复杂的图像降解的挑战，此任务非常困难。现有的SR方法要么假定预定义的模糊内核或固定噪声，这限制了这些方法在具有挑战性的情况下。在本文中，我们提出了一个用于盲目超级分辨率（DMSR）的降解引导的元修复网络，该网络促进了真实病例的图像恢复。 DMSR由降解提取器和元修复模块组成。萃取器估计LR输入中的降解，并指导元恢复模块以预测恢复参数的恢复参数。 DMSR通过新颖的降解一致性损失和重建损失共同优化。通过这样的优化，DMSR在三个广泛使用的基准上以很大的边距优于SOTA。一项包括16个受试者的用户研究进一步验证了现实世界中的盲目SR任务中DMSR的优势。

Axie Infinity是一款复杂的纸牌游戏，具有巨大的动作空间。这使得很难使用通用增强学习（RL）算法解决这一挑战。我们提出了一个混合RL框架来学习行动表示和游戏策略。为了避免评估大型可行动作集中的每个动作，我们的方法评估使用动作表示确定的固定大小集中的动作。我们将方法的性能与其他两个基线方法的样本效率和受过训练模型的获胜率进行了比较。我们从经验上表明，我们的方法达到了三种方法中总体上最佳的获胜率和最佳样本效率。

在线评论使消费者能够与公司聘用并提供重要的反馈。由于高维文本的复杂性，这些评论通常被简化为单一数值分数，例如评级或情绪评分。这项工作经验检查了用户生成的在线评论的因果效果对粒度水平：我们考虑多个方面，例如餐厅的食品和服务。了解消费者对不同方面的意见可以帮助详细评估业务绩效并有效地战略业务运营。具体来说，我们的目标是回答介入问题，例如餐厅人气将是什么，如果质量为本。它的方面服务增加了10％？对观测数据的因果推断的定义挑战是存在“混淆”，这可能不会被观察或测量，例如消费者对食品类型的偏好，使得估计效应偏差和高方差。为了解决这一挑战，我们求助于多模态代理，例如消费者简介信息和消费者和企业之间的互动。我们展示了如何有效利用丰富的信息来识别和估算在线评论中嵌入多个方面的因果效果。对综合和现实世界数据的实证评估证实了对拟议方法的可操作洞察力的功效和脱落。

社交媒体的回声室是一个重要的问题，可以引起许多负面后果，最近影响对Covid-19的响应。回声室促进病毒的阴谋理论，发现与疫苗犹豫不决，较少遵守面具授权，以及社会疏散的实践。此外，回声室的问题与政治极化等其他相关问题相连，以及误导的传播。回声室被定义为用户网络，用户只与支持其预先存在的信仰和意见的意见相互作用，并且他们排除和诋毁其他观点。本调查旨在从社会计算的角度检查社交媒体上的回声室现象，并为可能的解决方案提供蓝图。我们调查了相关文献，了解回声室的属性以及它们如何影响个人和社会。此外，我们展示了算法和心理的机制，这导致了回声室的形成。这些机制可以以两种形式表现出：（1）社交媒体推荐系统的偏见和（2）内部偏见，如确认偏见和精梳性。虽然减轻内部偏见是非常挑战的，但努力消除推荐系统的偏见。这些推荐系统利用我们自己的偏见来个性化内容建议，以使我们参与其中才能观看更多广告。因此，我们进一步研究了回声室检测和预防的不同计算方法，主要基于推荐系统。

因果推理中的一个重要问题是分解治疗结果对不同因果途径的总效果，并量化每种途径中的因果效果。例如，在因果公平中，作为男性雇员的总效果（即治疗）构成了对年收入（即，结果）的直接影响，并通过员工的职业（即调解人）和间接效应。因果调解分析（CMA）是一个正式的统计框架，用于揭示这种潜在的因果机制。 CMA在观察研究中的一个主要挑战正在处理混淆，导致治疗，调解员和结果之间导致虚假因果关系的变量。常规方法假设暗示可以测量所有混血器的顺序忽略性，这在实践中通常是不可核法的。这项工作旨在规避严格的顺序忽略性假设，并考虑隐藏的混杂。借鉴代理策略和深度学习的最新进展，我们建议同时揭示特征隐藏混杂物的潜在变量，并估计因果效应。使用合成和半合成数据集的经验评估验证了所提出的方法的有效性。我们进一步展示了我们对因果公平分析的方法的潜力。