使用神经网络编码HyperGraphs的HyperGraph神经网络（HNNS）为建模数据中的高阶关系提供了一种有希望的方法，并进一步解决了基于此类高阶关系的相关预测任务。但是，实践中的高阶关系包含复杂的模式，通常是高度不规则的。因此，设计一个足以表达这些关系的HNN在保持计算效率的同时，通常是一项挑战。受到超图扩散算法的启发，这项工作提出了一种名为ED-HNN的新型HNN体系结构，该结构可证明可以代表任何可以建模广泛的高阶关系的连续均值超差扩散算子。 ED-HNN可以通过将超图的星形扩展与传递神经网络的标准消息相结合来有效地实现。 ED-HNN进一步在处理异性超图和建造深层模型方面表现出了极大的优势。我们评估了在9个现实世界中的HyperGraph数据集上进行节点分类的ED-HNN。 ED-HNN均匀地胜过这9个数据集的最佳基线，并在其中四个数据集中获得了超过2 \％$ \ uparrow $的预测准确性。

Graph-based learning is a rapidly growing sub-field of machine learning with applications in social networks, citation networks, and bioinformatics. One of the most popular models is graph attention networks. They were introduced to allow a node to aggregate information from features of neighbor nodes in a non-uniform way, in contrast to simple graph convolution which does not distinguish the neighbors of a node. In this paper, we study theoretically this expected behaviour of graph attention networks. We prove multiple results on the performance of graph attention mechanism for the problem of node classification for a contextual stochastic block model. Here the node features are obtained from a mixture of Gaussians and the edges from a stochastic block model. We show that in an "easy" regime, where the distance between the means of the Gaussians is large enough, graph attention is able to distinguish inter-class from intra-class edges, and thus it maintains the weights of important edges and significantly reduces the weights of unimportant edges. Consequently, we show that this implies perfect node classification. In the "hard" regime, we show that every attention mechanism fails to distinguish intra-class from inter-class edges. We evaluate our theoretical results on synthetic and real-world data.

以自我为中心的视频为人类行为的高保真建模提供了细粒度的信息。手和互动对象是理解观众的行为和意图的一个关键方面。我们提供了一个标记的数据集，该数据集由11,243张以egentric的图像组成，并在各种日常活动中与手动和物体相互作用的每个像素分割标签。我们的数据集是第一个标记详细的手动触点边界的数据集。我们介绍了一种上下文感知的组成数据增强技术，以适应YouTube Eginbecentric视频的分布。我们表明，我们的强大手动分割模型和数据集可以作为基础工具，以提高或启用几个下游视觉应用程序，包括手状态分类，视频活动识别，3D网格对手相互作用的3D网格重建以及视频的视频介绍。 - 以自我为中心的视频中的对象前景。数据集和代码可在以下网址找到：https：//github.com/owenzlz/egohos

Incorporating knowledge graph as side information has become a new trend in recommendation systems. Recent studies regard items as entities of a knowledge graph and leverage graph neural networks to assist item encoding, yet by considering each relation type individually. However, relation types are often too many and sometimes one relation type involves too few entities. We argue that it is not efficient nor effective to use every relation type for item encoding. In this paper, we propose a VRKG4Rec model (Virtual Relational Knowledge Graphs for Recommendation), which explicitly distinguish the influence of different relations for item representation learning. We first construct virtual relational graphs (VRKGs) by an unsupervised learning scheme. We also design a local weighted smoothing (LWS) mechanism for encoding nodes, which iteratively updates a node embedding only depending on the embedding of its own and its neighbors, but involve no additional training parameters. We also employ the LWS mechanism on a user-item bipartite graph for user representation learning, which utilizes encodings of items with relational knowledge to help training representations of users. Experiment results on two public datasets validate that our VRKG4Rec model outperforms the state-of-the-art methods. The implementations are available at https://github.com/lulu0913/VRKG4Rec.

昂贵的边界盒注释限制了对象检测任务的开发。因此，有必要专注于更具挑战性的对象检测的更具挑战性的任务。它要求检测器只有几个训练样本识别新型类别的对象。如今，许多采用类似于元学习的培训方式的现有流行方法已经达到了有希望的表现，例如meta r-CNN系列。但是，支持数据仅用作类的注意，以指导每次查询图像的检测。它们彼此的相关性仍未得到解释。此外，许多最近的作品将支持数据和查询图像视为独立分支，而无需考虑它们之间的关系。为了解决这个问题，我们提出了一个动态相关性学习模型，该模型利用查询图像上所有支持图像与目标区域（ROI）之间的关系来构建动态图卷积网络（GCN）。通过使用此GCN的输出调整基本检测器的预测分布，提出的模型是一项硬辅助分类任务，该任务指导检测器隐含地改进类表示。对Pascal VOC和MS-Coco数据集进行了全面的实验。拟议的模型达到了最佳的整体性能，这表明了其学习更多广义特征的有效性。我们的代码可在https://github.com/liuweijie19980216/drl-for-fsod上找到。

多臂匪徒（MAB）提供了一种原则性的在线学习方法，以达到探索和剥削之间的平衡。由于表现出色和反馈学习低，没有学习在多种情况下采取行动，因此多臂匪徒在诸如推荐系统等应用程序中引起了广泛的关注。同样，在推荐系统中，协作过滤（CF）可以说是推荐系统中最早，最具影响力的方法。至关重要的是，新用户和不断变化的推荐项目池是推荐系统需要解决的挑战。对于协作过滤，经典方法是训练模型离线，然后执行在线测试，但是这种方法无法再处理用户偏好的动态变化，即所谓的冷启动。那么，如何在没有有效信息的情况下有效地向用户推荐项目？为了解决上述问题，已经提出了一个基于多臂强盗的协作过滤推荐系统，名为BanditMF。 BANDITMF旨在解决多军强盗算法和协作过滤中的两个挑战：（1）如何在有效信息稀缺的条件下解决冷启动问题以进行协作过滤，（2）强大社会关系域中的强盗算法问题是由独立估计与每个用户相关的未知参数并忽略用户之间的相关性引起的。

Dataset distillation has emerged as a prominent technique to improve data efficiency when training machine learning models. It encapsulates the knowledge from a large dataset into a smaller synthetic dataset. A model trained on this smaller distilled dataset can attain comparable performance to a model trained on the original training dataset. However, the existing dataset distillation techniques mainly aim at achieving the best trade-off between resource usage efficiency and model utility. The security risks stemming from them have not been explored. This study performs the first backdoor attack against the models trained on the data distilled by dataset distillation models in the image domain. Concretely, we inject triggers into the synthetic data during the distillation procedure rather than during the model training stage, where all previous attacks are performed. We propose two types of backdoor attacks, namely NAIVEATTACK and DOORPING. NAIVEATTACK simply adds triggers to the raw data at the initial distillation phase, while DOORPING iteratively updates the triggers during the entire distillation procedure. We conduct extensive evaluations on multiple datasets, architectures, and dataset distillation techniques. Empirical evaluation shows that NAIVEATTACK achieves decent attack success rate (ASR) scores in some cases, while DOORPING reaches higher ASR scores (close to 1.0) in all cases. Furthermore, we conduct a comprehensive ablation study to analyze the factors that may affect the attack performance. Finally, we evaluate multiple defense mechanisms against our backdoor attacks and show that our attacks can practically circumvent these defense mechanisms.

Blind image quality assessment (BIQA) remains challenging due to the diversity of distortion and image content variation, which complicate the distortion patterns crossing different scales and aggravate the difficulty of the regression problem for BIQA. However, existing BIQA methods often fail to consider multi-scale distortion patterns and image content, and little research has been done on learning strategies to make the regression model produce better performance. In this paper, we propose a simple yet effective Progressive Multi-Task Image Quality Assessment (PMT-IQA) model, which contains a multi-scale feature extraction module (MS) and a progressive multi-task learning module (PMT), to help the model learn complex distortion patterns and better optimize the regression issue to align with the law of human learning process from easy to hard. To verify the effectiveness of the proposed PMT-IQA model, we conduct experiments on four widely used public datasets, and the experimental results indicate that the performance of PMT-IQA is superior to the comparison approaches, and both MS and PMT modules improve the model's performance.

The development of social media user stance detection and bot detection methods rely heavily on large-scale and high-quality benchmarks. However, in addition to low annotation quality, existing benchmarks generally have incomplete user relationships, suppressing graph-based account detection research. To address these issues, we propose a Multi-Relational Graph-Based Twitter Account Detection Benchmark (MGTAB), the first standardized graph-based benchmark for account detection. To our knowledge, MGTAB was built based on the largest original data in the field, with over 1.55 million users and 130 million tweets. MGTAB contains 10,199 expert-annotated users and 7 types of relationships, ensuring high-quality annotation and diversified relations. In MGTAB, we extracted the 20 user property features with the greatest information gain and user tweet features as the user features. In addition, we performed a thorough evaluation of MGTAB and other public datasets. Our experiments found that graph-based approaches are generally more effective than feature-based approaches and perform better when introducing multiple relations. By analyzing experiment results, we identify effective approaches for account detection and provide potential future research directions in this field. Our benchmark and standardized evaluation procedures are freely available at: https://github.com/GraphDetec/MGTAB.

Given the increasingly intricate forms of partial differential equations (PDEs) in physics and related fields, computationally solving PDEs without analytic solutions inevitably suffers from the trade-off between accuracy and efficiency. Recent advances in neural operators, a kind of mesh-independent neural-network-based PDE solvers, have suggested the dawn of overcoming this challenge. In this emerging direction, Koopman neural operator (KNO) is a representative demonstration and outperforms other state-of-the-art alternatives in terms of accuracy and efficiency. Here we present KoopmanLab, a self-contained and user-friendly PyTorch module of the Koopman neural operator family for solving partial differential equations. Beyond the original version of KNO, we develop multiple new variants of KNO based on different neural network architectures to improve the general applicability of our module. These variants are validated by mesh-independent and long-term prediction experiments implemented on representative PDEs (e.g., the Navier-Stokes equation and the Bateman-Burgers equation) and ERA5 (i.e., one of the largest high-resolution data sets of global-scale climate fields). These demonstrations suggest the potential of KoopmanLab to be considered in diverse applications of partial differential equations.