This paper revisits building machine learning algorithms that involve interactions between entities, such as those between financial assets in an actively managed portfolio, or interactions between users in a social network. Our goal is to forecast the future evolution of ensembles of multivariate time series in such applications (e.g., the future return of a financial asset or the future popularity of a Twitter account). Designing ML algorithms for such systems requires addressing the challenges of high-dimensional interactions and non-linearity. Existing approaches usually adopt an ad-hoc approach to integrating high-dimensional techniques into non-linear models and recent studies have shown these approaches have questionable efficacy in time-evolving interacting systems. To this end, we propose a novel framework, which we dub as the additive influence model. Under our modeling assumption, we show that it is possible to decouple the learning of high-dimensional interactions from the learning of non-linear feature interactions. To learn the high-dimensional interactions, we leverage kernel-based techniques, with provable guarantees, to embed the entities in a low-dimensional latent space. To learn the non-linear feature-response interactions, we generalize prominent machine learning techniques, including designing a new statistically sound non-parametric method and an ensemble learning algorithm optimized for vector regressions. Extensive experiments on two common applications demonstrate that our new algorithms deliver significantly stronger forecasting power compared to standard and recently proposed methods.

在现实世界中，签名的定向网络无处不在。但是，对于分析此类网络的方法，较少的工作提出了频谱图神经网络（GNN）方法。在这里，我们介绍了一个签名的定向拉普拉斯矩阵，我们称之为磁性签名的laplacian，作为在签名的图表上签名的laplacian的自然概括，在有向图上的磁Laplacian。然后，我们使用此矩阵来构建一种新型的光谱GNN结构，并在节点聚类和链接预测任务上进行广泛的实验。在这些实验中，我们考虑了与签名信息有关的任务，与定向信息相关的任务以及与签名和定向信息有关的任务。我们证明，我们提出的光谱GNN有效地合并了签名和定向信息，并在广泛的数据集中获得领先的性能。此外，我们提供了一种新颖的合成网络模型，我们称之为签名的定向随机块模型，以及许多基于财务时间序列中铅滞后关系的新型现实世界数据集。

网络在许多现实世界应用程序中无处不在（例如，编码信任/不信任关系的社交网络，由时间序列数据引起的相关网络）。尽管许多网络都是签名或指示的，或者两者都在图形神经网络（GNN）上缺少统一的软件包，专门为签名和定向网络设计。在本文中，我们提出了Pytorch几何签名的指示，这是一个填补此空白的软件包。在此过程中，我们还提供了简短的审查调查，以分析签名和定向网络的分析，讨论相关实验中使用的数据，提供提出的方法概述，并通过实验评估实施方法。深度学习框架包括易于使用的GNN模型，合成和现实世界数据，以及针对签名和定向网络的特定任务评估指标和损失功能。作为Pytorch几何形状的扩展库，我们提出的软件由开源版本，详细文档，连续集成，单位测试和代码覆盖范围检查维护。我们的代码可在\ url {https://github.com/sherylhyx/pytorch_geometric_signed_directed}上公开获得。

从成对比较中恢复全球排名从时间同步到运动队排名的广泛应用。对应于竞争中匹配的成对比较可以解释为有向图（Digraph）中的边缘，其节点代表例如竞争对手的排名未知。在本文中，我们通过提出所谓的Gnnrank，这是一种基于Digraph嵌入的基于训练的GNN框架，将神经网络引入排名恢复问题。此外，设计了新的目标来编码排名upsess/违规行为。该框架涉及一种排名得分估计方法，并通过展开从可学习的相似性矩阵构建的图形的fiedler矢量计算来增加电感偏差。广泛数据集的实验结果表明，我们的方法具有竞争性，并且通常对基准的表现卓越，并且表现出了有希望的转移能力。代码和预处理数据为：\ url {https://github.com/sherylhyx/gnnrank}。

我们提出了一个分散的“Local2Global”的图形表示学习方法，即可以先用来缩放任何嵌入技术。我们的Local2Global方法首先将输入图分成重叠的子图（或“修补程序”）并独立地培训每个修补程序的本地表示。在第二步中，我们通过估计使用来自贴片重叠的信息的刚性动作的一组刚性运动来将本地表示将本地表示与全局一致的表示。 Local2Global相对于现有工作的关键区别特征是，在分布式训练期间无需经常昂贵的参数同步训练曲线的培训。这允许Local2Global缩放到大规模的工业应用，其中输入图甚至可能均不适合存储器，并且可以以分布式方式存储。我们在不同大小的数据集上应用Local2Global，并表明我们的方法在边缘重建和半监督分类上的规模和准确性之间实现了良好的权衡。我们还考虑异常检测的下游任务，并展示如何使用Local2Global在网络安全网络中突出显示异常。

节点群集是网络分析的强大工具。我们介绍了一个图形神经网络框架，以自我监督的方式获得定向网络的节点嵌入，包括一种新型的概率不平衡损失，可用于网络群集。在这里，我们提出了与方向性密切相关的定向流量不平衡度量，即使簇之间没有密度差，也可以揭示网络中的簇。与文献中的标准方法相反，在本文中，方向性不被视为滋扰，而是包含主要信号。与现有的图形神经网络方法不同，DIGRAC优化了用于聚类的有向流动不平衡无需标签监督，并且与现有的光谱方法不同，并且可以自然合并节点特征。关于合成数据的广泛实验结果，以定向随机块模型的形式，以及不同尺度的现实世界数据，证明我们的方法基于流量不平衡，在比较时在有向图聚类上获得最先进的结果针对文献中的10种最先进方法，用于广泛的噪声和稀疏度，图形结构和拓扑，甚至超过监督方法。

Models of sensory processing and learning in the cortex need to efficiently assign credit to synapses in all areas. In deep learning, a known solution is error backpropagation, which however requires biologically implausible weight transport from feed-forward to feedback paths. We introduce Phaseless Alignment Learning (PAL), a bio-plausible method to learn efficient feedback weights in layered cortical hierarchies. This is achieved by exploiting the noise naturally found in biophysical systems as an additional carrier of information. In our dynamical system, all weights are learned simultaneously with always-on plasticity and using only information locally available to the synapses. Our method is completely phase-free (no forward and backward passes or phased learning) and allows for efficient error propagation across multi-layer cortical hierarchies, while maintaining biologically plausible signal transport and learning. Our method is applicable to a wide class of models and improves on previously known biologically plausible ways of credit assignment: compared to random synaptic feedback, it can solve complex tasks with less neurons and learn more useful latent representations. We demonstrate this on various classification tasks using a cortical microcircuit model with prospective coding.

Autonomous driving is an exciting new industry, posing important research questions. Within the perception module, 3D human pose estimation is an emerging technology, which can enable the autonomous vehicle to perceive and understand the subtle and complex behaviors of pedestrians. While hardware systems and sensors have dramatically improved over the decades -- with cars potentially boasting complex LiDAR and vision systems and with a growing expansion of the available body of dedicated datasets for this newly available information -- not much work has been done to harness these novel signals for the core problem of 3D human pose estimation. Our method, which we coin HUM3DIL (HUMan 3D from Images and LiDAR), efficiently makes use of these complementary signals, in a semi-supervised fashion and outperforms existing methods with a large margin. It is a fast and compact model for onboard deployment. Specifically, we embed LiDAR points into pixel-aligned multi-modal features, which we pass through a sequence of Transformer refinement stages. Quantitative experiments on the Waymo Open Dataset support these claims, where we achieve state-of-the-art results on the task of 3D pose estimation.

We present PhoMoH, a neural network methodology to construct generative models of photorealistic 3D geometry and appearance of human heads including hair, beards, clothing and accessories. In contrast to prior work, PhoMoH models the human head using neural fields, thus supporting complex topology. Instead of learning a head model from scratch, we propose to augment an existing expressive head model with new features. Concretely, we learn a highly detailed geometry network layered on top of a mid-resolution head model together with a detailed, local geometry-aware, and disentangled color field. Our proposed architecture allows us to learn photorealistic human head models from relatively little data. The learned generative geometry and appearance networks can be sampled individually and allow the creation of diverse and realistic human heads. Extensive experiments validate our method qualitatively and across different metrics.

We introduce Structured 3D Features, a model based on a novel implicit 3D representation that pools pixel-aligned image features onto dense 3D points sampled from a parametric, statistical human mesh surface. The 3D points have associated semantics and can move freely in 3D space. This allows for optimal coverage of the person of interest, beyond just the body shape, which in turn, additionally helps modeling accessories, hair, and loose clothing. Owing to this, we present a complete 3D transformer-based attention framework which, given a single image of a person in an unconstrained pose, generates an animatable 3D reconstruction with albedo and illumination decomposition, as a result of a single end-to-end model, trained semi-supervised, and with no additional postprocessing. We show that our S3F model surpasses the previous state-of-the-art on various tasks, including monocular 3D reconstruction, as well as albedo and shading estimation. Moreover, we show that the proposed methodology allows novel view synthesis, relighting, and re-posing the reconstruction, and can naturally be extended to handle multiple input images (e.g. different views of a person, or the same view, in different poses, in video). Finally, we demonstrate the editing capabilities of our model for 3D virtual try-on applications.