VLDB 2026 Research / reviewers in the wild / expert
Yao Zhang 0009
dblp:57/3892-9
· DBLP profile ↗
33ranked-venue papers in the field
8as first author
26since 2021 · last 2025
0000-0003-1481-8826ORCID · conflict
Domains — venue-derived; a paper can count in several
Data Mining & Knowledge Discovery · 15 (2 first)Information Retrieval & Web Search · 12 (4 first)Database Systems & Data Management · 6 (2 first)
| Year | Publication | Venue | Position |
|---|---|---|---|
| 2025 | Deep reinforcement learning for community architectural layout generation
Yun Xiong, Haofen Wang, Yao Zhang 0009, Weinan Zhang 0001 |
Knowl. Inf. Syst. | 4 |
| 2025 | CauseRuDi: Explaining Behavior Sequence Models by Causal Statistics Generation and Rule DistillationabstractRisk scoring systems have been widely deployed in many applications, which assign risk scores to users according to their behavior sequences. Though many deep learning methods with sophisticated designs have achieved promising results, the black-box nature hinders their applications due to fairness, explainability, and compliance consideration. Rule-based systems are considered reliable in these sensitive scenarios. However, building a rule system is labor-intensive. Experts need to find informative statistics from user behavior sequences, design rules based on statistics and assign weights to each rule. In this paper, we bridge the gap between effective but black-box models and transparent rule models. We propose a two-stage framework, CauseRuDi, that distills the knowledge of black-box teacher models into rule-based student models. We design a Monte Carlo tree search-based statistics generation method that maximizes the correlation or dependence between the generated statistics and the teacher model's outputs. We formulate a sequential move game and a simultaneous move coalitional game to generate multiple statistics. Then statistics are composed into logical rules with our proposed neural logical networks by mimicking the outputs of teacher models. We evaluate CauseRuDi on three real-world public datasets and an industrial dataset to demonstrate its effectiveness. Yao Zhang 0009, Yun Xiong, Yiheng Sun, Tian Lu 0002, Shengli Sun |
IEEE Trans. Knowl. Data Eng. | 1 |
| 2024 | DTFormer: A Transformer-Based Method for Discrete-Time Dynamic Graph Representation LearningabstractDiscrete-Time Dynamic Graphs (DTDGs), which are prevalent in real-world implementations and notable for their ease of data acquisition, have garnered considerable attention from both academic researchers and industry practitioners. The representation learning of DTDGs has been extensively applied to model the dynamics of temporally changing entities and their evolving connections. Currently, DTDG representation learning predominantly relies on GNN+RNN architectures, which manifest the inherent limitations of both Graph Neural Networks (GNNs) and Recurrent Neural Networks (RNNs). GNNs suffer from the over-smoothing issue as the models architecture goes deeper, while RNNs struggle to capture long-term dependencies effectively. GNN+RNN architectures also grapple with scaling to large graph sizes and long sequences. Additionally, these methods often compute node representations separately and focus solely on individual node characteristics, thereby overlooking the behavior intersections between the two nodes whose link is being predicted, such as instances where the two nodes appear together in the same context or share common neighbors. Xi Chen 0072, Yun Xiong, Siwei Zhang 0001, Jiawei Zhang 0001, Yao Zhang 0009, Xixi Wu, Mingyang Zhang 0004, Tengfei Liu 0007, Weiqiang Wang 0002 |
CIKM | 5 |
| 2024 | Towards Adaptive Neighborhood for Advancing Temporal Interaction Graph ModelingabstractTemporal Graph Networks (TGNs) have demonstrated their remarkable performance in modeling temporal interaction graphs. These works can generate temporal node representations by encoding the surrounding neighborhoods for the target node. However, an inherent limitation of existing TGNs is their reliance onfixed, hand-crafted rules for neighborhood encoding, overlooking the necessity for an adaptive and learnable neighborhood that can accommodate both personalization and temporal evolution across different timestamps. In this paper, we aim to enhance existing TGNs by introducing anadaptive neighborhood encoding mechanism. We present SEAN (Selective Encoding for Adaptive Neighborhood), a flexible plug-and-play model that can be seamlessly integrated with existing TGNs, effectively boosting their performance. To achieve this, we decompose the adaptive neighborhood encoding process into two phases: (i) representative neighbor selection, and (ii) temporal-aware neighborhood information aggregation. Specifically, we propose the Representative Neighbor Selector component, which automatically pinpoints the most important neighbors for the target node. It offers a tailored understanding of each node's unique surrounding context, facilitating personalization. Subsequently, we propose a Temporal-aware Aggregator, which synthesizes neighborhood aggregation by selectively determining the utilization of aggregation routes and decaying the outdated information, allowing our model to adaptively leverage both the contextually significant and current information during aggregation. We conduct extensive experiments by integrating SEAN into three representative TGNs, evaluating their performance on four public datasets and one financial benchmark dataset introduced in this paper. The results demonstrate that SEAN consistently leads to performance improvements across all models, achieving SOTA performance and exceptional robustness. Siwei Zhang 0001, Xi Chen 0072, Yun Xiong, Xixi Wu, Yao Zhang 0009, Yongrui Fu, Yinglong Zhao, Jiawei Zhang 0001 |
KDD | 5 |
| 2024 | ProCom: A Few-shot Targeted Community Detection AlgorithmabstractTargeted community detection aims to distinguish a particular type of community in the network. This is an important task with a lot of real-world applications, e.g., identifying fraud groups in transaction networks. Traditional community detection methods fail to capture the specific features of the targeted community and detect all types of communities indiscriminately. Semi-supervised community detection algorithms, emerged as a feasible alternative, are inherently constrained by their limited adaptability and substantial reliance on a large amount of labeled data, which demands extensive domain knowledge and manual effort. Xixi Wu, Kaiyu Xiong, Yun Xiong, Xiao-Xin He, Yao Zhang 0009, Yizhu Jiao, Jiawei Zhang 0001 |
KDD | 5 |
| 2024 | Microservice Root Cause Analysis With Limited Observability Through Intervention Recognition in the Latent SpaceabstractMany failure root cause analysis (RCA) algorithms for microservices have been proposed with the widespread adoption of microservices systems. Existing algorithms generally focus on RCA with ranking single-level (e.g. metric-level or service-level) root cause candidates (RCCs) with comprehensive monitoring metrics. However, many heterogeneous RCCs exist with limited observability in real-world microservices systems. Further, we find that the limited observability may result in inaccurate RCA through real-world failures in eBay. In this paper, for the first time, we propose to "model RCCs as latent variables". The core idea is to infer the status of RCCs as latent variables with related monitoring metrics instead of directly extracting features from only the observable metrics. Based on this, we propose LatentScope, an unsupervised RCA framework with heterogeneous RCCs under limited observability. A dual-space graph is proposed to model both observable and unobservable variables, with many-to-many relationships between spaces. To achieve fast inference of latent variables and RCA, we propose the LatentRegressor algorithm, which includes Regression-based Latent-space Intervention Recognition (RLIR) to achieve intervention recognition-based RCA in latent space. LatentScope has been deployed in eBay's production environment and evaluated on both eBay's real-world failures and a testbed dataset. The evaluation results show that, compared with baseline algorithms, our model significantly improves the Top-1 recall by 9.7%-57.9%. The source code of LatentScope and the dataset are available at https://github.com/NetManAIOps/LatentScope. Zhe Xie, Shenglin Zhang, Yitong Geng, Yao Zhang 0009, Minghua Ma, Xiaohui Nie, Zhenhe Yao, Longlong Xu, Yongqian Sun, Dan Pei |
KDD | 4 |
| 2023 | Dual Intents Graph Modeling for User-centric Group DiscoveryabstractOnline groups have become increasingly prevalent, providing users with space to share experiences and explore interests. Therefore, user-centric group discovery task, i.e., recommending groups to users can help both users' online experiences and platforms' long-term developments. Existing recommender methods can not deal with this task as modeling user-group participation into a bipartite graph overlooks their item-side interests. Although there exist a few works attempting to address this task, they still fall short in fully preserving the social context and ensuring effective interest representation learning. Xixi Wu, Yun Xiong, Yao Zhang 0009, Yizhu Jiao, Jiawei Zhang 0001 |
CIKM | 3 |
| 2023 | iLoRE: Dynamic Graph Representation with Instant Long-term Modeling and Re-occurrence PreservationabstractContinuous-time dynamic graph modeling is a crucial task for many real-world applications, such as financial risk management and fraud detection. Though existing dynamic graph modeling methods have achieved satisfactory results, they still suffer from three key limitations, hindering their scalability and further applicability. i) Indiscriminate updating. For incoming edges, existing methods would indiscriminately deal with them, which may lead to more time consumption and unexpected noisy information. ii) Ineffective node-wise long-term modeling. They heavily rely on recurrent neural networks (RNNs) as a backbone, which has been demonstrated to be incapable of fully capturing node-wise long-term dependencies in event sequences. iii) Neglect of re-occurrence patterns. Dynamic graphs involve the repeated occurrence of neighbors that indicates their importance, which is disappointedly neglected by existing methods. Siwei Zhang 0001, Yun Xiong, Yao Zhang 0009, Xixi Wu, Yiheng Sun, Jiawei Zhang 0001 |
CIKM | 3 |
| 2023 | RDGSL: Dynamic Graph Representation Learning with Structure LearningabstractTemporal Graph Networks (TGNs) have shown remarkable performance in learning representation for continuous-time dynamic graphs. However, real-world dynamic graphs typically contain diverse and intricate noise. Noise can significantly degrade the quality of representation generation, impeding the effectiveness of TGNs in downstream tasks. Though structure learning is widely applied to mitigate noise in static graphs, its adaptation to dynamic graph settings poses two significant challenges. i) Noise dynamics. Existing structure learning methods are ill-equipped to address the temporal aspect of noise, hampering their effectiveness in such dynamic and ever-changing noise patterns. ii) More severe noise. Noise may be introduced along with multiple interactions between two nodes, leading to the re-pollution of these nodes and consequently causing more severe noise compared to static graphs. Siwei Zhang 0001, Yun Xiong, Yao Zhang 0009, Yiheng Sun, Xi Chen 0072, Yizhu Jiao, Yangyong Zhu |
CIKM | 3 |
| 2023 | Automatic ICD Coding Based on Segmented ClinicalBERT with Hierarchical Tree Structure Learning
Beichen Kang, Xiaosu Wang, Yun Xiong, Yao Zhang 0009, Chaofan Zhou, Yangyong Zhu, Jiawei Zhang 0001, Chunlei Tang |
DASFAA (4) | 4 |
| 2023 | MulEA: Multi-type Entity Alignment of Heterogeneous Medical Knowledge Graphs
Mingxia Wang, Yun Xiong, Jingwen Yue, Yao Zhang 0009, Chunlei Tang |
DASFAA (2) | 5 |
| 2023 | Hierarchical Encoder-Decoder with Addressable Memory Network for Diagnosis Prediction
Mingxia Wang, Yun Xiong, Yao Zhang 0009, Philip S. Yu, Yangyong Zhu |
DASFAA (4) | 3 |
| 2023 | DynamiSE: Dynamic Signed Network Embedding for Link PredictionabstractIn real-world scenarios, dynamic signed networks are ubiquitous where edges have positive and negative sign semantics and evolve over time. Encoding the dynamics and sign semantics of the network simultaneously is challenging. Moreover, over-smoothing is inevitably introduced by the learning of network dynamics. Targeting this gap, we propose Dynamic Signed Network Embedding (DynamiSE), which effectively integrates the balance theory and ordinary differential equation (ODE) into node representation learning to construct a deeper dynamic signed graph neural network and capture the complex sign semantics formed by the two types of edges. Haiting Sun, Yun Xiong, Yao Zhang 0009, Yali Xiang, Xing Jia, Haofen Wang |
DSAA | 4 |
| 2023 | Reducing Negative Effects of the Biases of Language Models in Zero-Shot SettingabstractPre-trained language models (PLMs) such as GPTs have been revealed to be biased towards certain target classes because of the prompt and the model's intrinsic biases. In contrast to the fully supervised scenario where there are a large number of costly labeled samples that can be used to fine-tune model parameters to correct for biases, there are no labeled samples available for the zero-shot setting. We argue that a key to calibrating the biases of a PLM on a target task in zero-shot setting lies in detecting and estimating the biases, which remains a challenge. In this paper, we first construct probing samples with the randomly generated token sequences, which are simple but effective in detecting inputs for stimulating GPTs to show the biases; and we pursue an in-depth research on the plausibility of utilizing class scores for the probing samples to reflect and estimate the biases of GPTs on a downstream target task. Furtherly, in order to effectively utilize the probing samples and thus reduce negative effects of the biases of GPTs, we propose a lightweight model Calibration Adapter (CA) along with a self-guided training strategy that carries out distribution-level optimization, which enables us to take advantage of the probing samples to fine-tune and select only the proposed CA, respectively, while keeping the PLM encoder frozen. To demonstrate the effectiveness of our study, we have conducted extensive experiments, where the results indicate that the calibration ability acquired by CA on the probing samples can be successfully transferred to reduce negative effects of the biases of GPTs on a downstream target task, and our approach can yield better performance than state-of-the-art (SOTA) models in zero-shot settings. Xiaosu Wang, Yun Xiong, Beichen Kang, Yao Zhang 0009, Philip S. Yu, Yangyong Zhu |
WSDM | 4 |
| 2023 | ConsRec: Learning Consensus Behind Interactions for Group RecommendationabstractSince group activities have become very common in daily life, there is an urgent demand for generating recommendations for a group of users, referred to as group recommendation task. Existing group recommendation methods usually infer groups’ preferences via aggregating diverse members’ interests. Actually, groups’ ultimate choice involves compromises between members, and finally, an agreement can be reached. However, existing individual information aggregation lacks a holistic group-level consideration, failing to capture the consensus information. Besides, their specific aggregation strategies either suffer from high computational costs or become too coarse-grained to make precise predictions. Xixi Wu, Yun Xiong, Yao Zhang 0009, Yizhu Jiao, Jiawei Zhang 0001, Yangyong Zhu, Philip S. Yu |
WWW | 3 |
| 2023 | TIGER: Temporal Interaction Graph Embedding with RestartsabstractTemporal interaction graphs (TIGs), consisting of sequences of timestamped interaction events, are prevalent in fields like e-commerce and social networks. To better learn dynamic node embeddings that vary over time, researchers have proposed a series of temporal graph neural networks for TIGs. However, due to the entangled temporal and structural dependencies, existing methods have to process the sequence of events chronologically and consecutively to ensure node representations are up-to-date. This prevents existing models from parallelization and reduces their flexibility in industrial applications. To tackle the above challenge, in this paper, we propose TIGER, a TIG embedding model that can restart at any timestamp. We introduce a restarter module that generates surrogate representations acting as the warm initialization of node representations. By restarting from multiple timestamps simultaneously, we divide the sequence into multiple chunks and naturally enable the parallelization of the model. Moreover, in contrast to previous models that utilize a single memory unit, we introduce a dual memory module to better exploit neighborhood information and alleviate the staleness problem. Extensive experiments on four public datasets and one industrial dataset are conducted, and the results verify both the effectiveness and the efficiency of our work. Yao Zhang 0009, Yun Xiong, Yongxiang Liao, Yiheng Sun, Xuehao Zheng, Yangyong Zhu |
WWW | 1 |
| 2023 | Temporal super-resolution traffic flow forecasting via continuous-time network dynamics
Yi Xie 0003, Yun Xiong, Jiawei Zhang 0001, Chao Chen 0004, Yao Zhang 0009, Jie Zhao 0022, Yizhu Jiao, Jinjing Zhao, Yangyong Zhu |
Knowl. Inf. Syst. | 5 |
| 2022 | RuDi: Explaining Behavior Sequence Models by Automatic Statistics Generation and Rule DistillationabstractRisk scoring systems have been widely deployed in many applications, which assign risk scores to users according to their behavior sequences. Though many deep learning methods with sophisticated designs have achieved promising results, the black-box nature hinders their applications due to fairness, explainability, and compliance consideration. Rule-based systems are considered reliable in these sensitive scenarios. However, building a rule system is labor-intensive. Experts need to find informative statistics from user behavior sequences, design rules based on statistics and assign weights to each rule. In this paper, we bridge the gap between effective but black-box models and transparent rule models. We propose a two-stage method, RuDi, that distills the knowledge of black-box teacher models into rule-based student models. We design a Monte Carlo tree search-based statistics generation method that can provide a set of informative statistics in the first stage. Then statistics are composed into logical rules with our proposed neural logical networks by mimicking the outputs of teacher models. We evaluate RuDi on three real-world public datasets and an industrial dataset to demonstrate its effectiveness. Yao Zhang 0009, Yun Xiong, Yiheng Sun, Tian Lu 0002, Yangyong Zhu |
CIKM | 1 |
| 2022 | CLARE: A Semi-supervised Community Detection AlgorithmabstractCommunity detection refers to the task of discovering closely related subgraphs to understand the networks. However, traditional community detection algorithms fail to pinpoint a particular kind of community. This limits its applicability in real-world networks, e.g., distinguishing fraud groups from normal ones in transaction networks. Recently, semi-supervised community detection emerges as a solution. It aims to seek other similar communities in the network with few labeled communities as training data. Existing works can be regarded as seed-based: locate seed nodes and then develop communities around seeds. However, these methods are quite sensitive to the quality of selected seeds since communities generated around a mis-detected seed may be irrelevant. Besides, they have individual issues, e.g., inflexibility and high computational overhead. To address these issues, we propose CLARE, which consists of two key components, Community Locator and Community Rewriter. Our idea is that we can locate potential communities and then refine them. Therefore, the community locator is proposed for quickly locating potential communities by seeking subgraphs that are similar to training ones in the network. To further adjust these located communities, we devise the community rewriter. Enhanced by deep reinforcement learning, it suggests intelligent decisions, such as adding or dropping nodes, to refine community structures flexibly. Extensive experiments verify both the effectiveness and efficiency of our work compared with prior state-of-the-art approaches on multiple real-world datasets. Xixi Wu, Yun Xiong, Yao Zhang 0009, Yizhu Jiao, Yiheng Sun, Yangyong Zhu, Philip S. Yu |
KDD | 3 |
| 2022 | Triangle Graph Interest Network for Click-through Rate PredictionabstractClick-through rate prediction is a critical task in online advertising. Currently, many existing methods attempt to extract user potential interests from historical click behavior sequences. However, it is difficult to handle sparse user behaviors or broaden interest exploration. Recently, some researchers incorporate the item-item co-occurrence graph as an auxiliary. Due to the elusiveness of user interests, those works still fail to determine the real motivation of user click behaviors. Besides, those works are more biased towards popular or similar commodities. They lack an effective mechanism to break the diversity restrictions. In this paper, we point out two special properties of triangles in the item-item graphs for recommendation systems: Intra-triangle homophily and Inter-triangle heterophiy. Based on this, we propose a novel and effective framework named Triangle Graph Interest Network (TGIN). For each clicked item in user behavior sequences, we introduce the triangles in its neighborhood of the item-item graphs as a supplement. TGIN regards these triangles as the basic units of user interests, which provide the clues to capture the real motivation for a user clicking an item. We characterize every click behavior by aggregating the information of several interest units to alleviate the elusive motivation problem. The attention mechanism determines users' preference for different interest units. By selecting diverse and relative triangles, \short brings in novel and serendipitous items to expand exploration opportunities of user interests. Then, we aggregate the multi-level interests of historical behavior sequences to improve CTR prediction. Extensive experiments on both of public and industrial datasets clearly verify the effectiveness of our framework. Wensen Jiang, Yizhu Jiao, Qingqin Wang, Chuanming Liang, Yao Zhang 0009, Zhijun Sun, Yun Xiong, Yangyong Zhu |
WSDM | 6 |
| 2022 | Scalable self-supervised graph representation learning via enhancing and contrasting subgraphs
Yizhu Jiao, Yun Xiong, Jiawei Zhang 0001, Yao Zhang 0009, Yangyong Zhu |
Knowl. Inf. Syst. | 4 |
| 2021 | How Powerful is Graph Convolution for Recommendation?abstractGraph convolutional networks (GCNs) have recently enabled a popular class of algorithms for collaborative filtering (CF). Nevertheless, the theoretical underpinnings of their empirical successes remain elusive. In this paper, we endeavor to obtain a better understanding of GCN-based CF methods via the lens of graph signal processing. By identifying the critical role of smoothness, a key concept in graph signal processing, we develop a unified graph convolution-based framework for CF. We prove that many existing CF methods are special cases of this framework, including the neighborhood-based methods, low-rank matrix factorization, linear auto-encoders, and LightGCN, corresponding to different low-pass filters. Based on our framework, we then present a simple and computationally efficient CF baseline, which we shall refer to as Graph Filter based Collaborative Filtering (GF-CF). Given an implicit feedback matrix, GF-CF can be obtained in a closed form instead of expensive training with back-propagation. Experiments will show that GF-CF achieves competitive or better performance against deep learning-based methods on three well-known datasets, notably with a 70% performance gain over LightGCN on the Amazon-book dataset. Yifei Shen 0004, Yao Zhang 0009, Jun Zhang 0004, Khaled Ben Letaief, Dongsheng Li 0002 |
CIKM | 3 |
| 2021 | CoPE: Modeling Continuous Propagation and Evolution on Interaction GraphabstractHuman interactions with items are being constantly logged, which enables advanced representation learning and facilitates various tasks. Instead of generating static embeddings at the end of training, several temporal embedding methods were recently proposed to learn user and item embeddings as functions of time, where each entity has a trajectory of embedding vectors aiming to encode the full dynamics. However, these methods may not be optimal to encode the dynamical behaviors on the interaction graphs in that they can not generate "fully''-temporal embeddings and do not consider information propagation. In this paper, we tackle the issues and propose CoPE (Co ntinuous P ropagation and E volution). We use an ordinary differential equation based graph neural network to model information propagation and more sophisticated evolution patterns. We train CoPE on sequences of interactions with the help of meta-learning to ensure fast adaptation to the most recent interactions. We evaluate CoPE on three tasks and prove its effectiveness. Yao Zhang 0009, Yun Xiong, Dongsheng Li 0002, Kan Ren, Yangyong Zhu |
CIKM | 1 |
| 2021 | HSGMP: Heterogeneous Scene Graph Message Passing for Cross-modal RetrievalabstractSemantic relationship information is important to the image-text retrieval task. Existing work usually extract relationship information by calculating the relationship value pairwise, which is hardly to find out a meaningful semantic relationship. A more reasonable method is to convert the modal to a scene graph, thereby explicitly modeling the relationship. Scene graph is a kind of graph data structure modeling the scene of modality. There are two concept in a scene graph, object and relationship. In image modal, object indicates the image region and relationship represents the predicate of the image regions. In text modal, object indicates the entity and relationship represents the association between entities, also known as semantic relationship. In image-text retrieval task, both object and relationship are important, and a key challenge is to obtain semantic information. In this paper, image and text are represented as two kinds of scene graphs: visual scene graph and textual scene graph, and then they are combined into Heterogeneous Scene Graph(HSG). By explicitly modeling relationships using directed graph, the information can be passed edge-wise. To further extract semantic information, we introduce the metapath, which can extract specific semantic information on specified path. Moreover, we propose Heterogeneous Message Passing(HMP) to communicate information on the metapath. After the message passing, the similarity of two modalities can be represented as the similarity of the graphs. Experiment shows that the model achieve competitive results on Flickr30K and MSCOCO, which indicates that our approach has advantages in image-text retrieval. Yun Xiong, Yao Zhang 0009, Yuwei Fu, Yangyong Zhu |
ICMR | 3 |
| 2021 | AutoCite: Multi-Modal Representation Fusion for Contextual Citation GenerationabstractCiting comprehensive and correct related work is crucial in academic writing. It can not only support the author's claims but also help readers trace other related research papers. Nowadays, with the rapid increase in the number of scientific literatures, it has become increasingly challenging to search for high-quality citations and write the manuscript. In this paper, we present an automatic writing assistant model, AutoCite, which not only infers potentially related work but also automatically generates the citation context at the same time. Specifically, AutoCite involves a novel multi-modal encoder and a multi-task decoder architecture. Based on the multi-modal inputs, the encoder in AutoCite learns paper representations with both citation network structure and textual contexts. The multi-task decoder in AutoCite couples and jointly learns citation prediction and context generation in a unified manner. To effectively join the encoder and decoder, we introduce a novel representation fusion component, i.e., gated neural fusion, which feeds the multi-modal representation inputs from the encoder and creates outputs for the downstream multi-task decoder adaptively. Extensive experiments on five real-world citation network datasets validate the effectiveness of our model. Qingqin Wang, Yun Xiong, Yao Zhang 0009, Jiawei Zhang 0001, Yangyong Zhu |
WSDM | 3 |
| 2021 | IGE+: A Framework for Learning Node Embeddings in Interaction GraphsabstractNode embedding techniques have gained prominence since they produce continuous and low-dimensional features, which are effective for various tasks. Most existing approaches learn node embeddings by exploring the structure of networks and are mainly focused on static non-attributed graphs. However, many real-world applications, such as stock markets and public review websites, involve bipartite graphs with dynamic and attributed edges, called attributed interaction graphs. Different from conventional graph data, attributed interaction graphs involve two kinds of entities (e.g. investors/stocks and users/businesses) and edges of temporal interactions with attributes (e.g. transactions and reviews). In this paper, we study the problem of node embedding in attributed interaction graphs. Learning embeddings in interaction graphs is highly challenging due to the dynamics and heterogeneous attributes of edges. Different from conventional static graphs, in attributed interaction graphs, each edge can have totally different meanings when the interaction is at different times or associated with different attributes. To tackle the above challenges, we introduce the temporal dependency and conditional proximity, which are two fundamental characteristics of interaction graphs. Then, we propose a deep node embedding method called IGE+ (Interaction Graph Embedding+). By preserving these two characteristics, IGE+ is able to produce effective node embeddings in interaction graphs. We evaluate our proposed method and various comparing methods on four real-world datasets. The experimental results prove the effectiveness of the learned embeddings by IGE+ on both node-based and edge-based tasks. Yao Zhang 0009, Yun Xiong, Xiangnan Kong, Zhuang Niu, Yangyong Zhu |
IEEE Trans. Knowl. Data Eng. | 1 |
| 2020 | CommDGI: Community Detection Oriented Deep Graph InfomaxabstractGraph Neural Networks(GNNs), like GCN and GAT, have achieved great success in a number of supervised or semi-supervised tasks including node classification and link prediction. These existing graph neural networks can effectively encode neighborhood information of graph nodes through their message aggregating mechanisms. However, there are some unsupervised and structure-related tasks like community detection, which is a fundamental problem in network analysis that finds densely-connected groups of nodes and separates them from others in graphs. It is still difficult for these general-purposed GNNs to learn the needed structural information in these particular problems. To overcome the shortcomings of general-purposed graph representation learning methods, we propose the Community Deep Graph Infomax (CommDGI), a graph neural network designed to handle community detection problems. Inspired by the success of deep graph infomax in self-supervised graph learning, we design a novel mutual information mechanism to capture neighborhood as well as community information in graphs. A trainable clustering layer is employed to learn the community partition in an end-to-end manner. Disentangled representation learning is applied in our graph neural network so that the model can improve interpretability and generalization. Throughout the whole learning process, joint optimization is applied to learn the community-related node representations. The experimental results show that our algorithm outperforms state-of-the-art community detection methods. Yun Xiong, Jiawei Zhang 0001, Yao Zhang 0009, Yizhu Jiao, Yangyong Zhu |
CIKM | 4 |
| 2020 | Sub-graph Contrast for Scalable Self-Supervised Graph Representation LearningabstractGraph representation learning has attracted lots of attention recently. Existing graph neural networks fed with the complete graph data are not scalable due to limited computation and memory costs. Thus, it remains a great challenge to capture rich information in large-scale graph data. Besides, these methods mainly focus on supervised learning and highly depend on node label information, which is expensive to obtain in the real world. As to unsupervised network embedding approaches, they overemphasize node proximity instead, whose learned representations can hardly be used in downstream application tasks directly. In recent years, emerging self-supervised learning provides a potential solution to address the aforementioned problems. However, existing self-supervised works also operate on the complete graph data and are biased to fit either global or very local (1-hop neighborhood) graph structures in defining the mutual information based loss terms. In this paper, a novel self-supervised representation learning method via Sub-graph Contrast, namely Subg-Con, is proposed by utilizing the strong correlation between central nodes and their sampled subgraphs to capture regional structure information. Instead of learning on the complete input graph data, with a novel data augmentation strategy, Subg-Con learns node representations through a contrastive loss defined based on subgraphs sampled from the original graph instead. Compared with existing graph representation learning approaches, Subg-Con has prominent performance advantages in weaker supervision requirements, model learning scalability, and parallelization. Extensive experiments verify both the effectiveness and the efficiency of our work compared with both classic and state-of-the-art graph representation learning approaches on multiple realworld large-scale benchmark datasets from different domains. Yizhu Jiao, Yun Xiong, Jiawei Zhang 0001, Yao Zhang 0009, Yangyong Zhu |
ICDM | 4 |
| 2020 | SEAL: Learning Heuristics for Community Detection with Generative Adversarial NetworksabstractCommunity detection is an important task with many applications. However, there is no universal definition of communities, and a variety of algorithms have been proposed based on different assumptions. In this paper, we instead study the semi-supervised community detection problem where we are given several communities in a network as training data and aim to discover more communities. This setting makes it possible to learn concepts of communities from data without any prior knowledge. We propose the Seed Expansion with generative Adversarial Learning (SEAL), a framework for learning heuristics for community detection. SEAL contains a generative adversarial network, where the discriminator predicts whether a community is real or fake, and the generator generates communities that cheat the discriminator by implicitly fitting characteristics of real ones. The generator is a graph neural network specialized in sequential decision processes and gets trained by policy gradient. Moreover, a locator is proposed to avoid well-known free-rider effects by forming a dual learning task with the generator. Last but not least, a seed selector is utilized to provide promising seeds to the generator. We evaluate SEAL on 5 real-world networks and prove its effectiveness. Yao Zhang 0009, Yun Xiong, Tengfei Liu 0007, Weiqiang Wang 0002, Yangyong Zhu, Philip S. Yu |
KDD | 1 |
| 2019 | DynGraphGAN: Dynamic Graph Embedding via Generative Adversarial Networks
Yun Xiong, Yao Zhang 0009, Hanjie Fu, Wei Wang 0010, Yangyong Zhu, Philip S. Yu |
DASFAA (1) | 2 |
| 2017 | Learning Node Embeddings in Interaction GraphsabstractNode embedding techniques have gained prominence since they produce continuous and low-dimensional features, which are effective for various tasks. Most existing approaches learn node embeddings by exploring the structure of networks and are mainly focused on static non-attributed graphs. However, many real-world applications, such as stock markets and public review websites, involve bipartite graphs with dynamic and attributed edges, called attributed interaction graphs. Different from conventional graph data, attributed interaction graphs involve two kinds of entities (e.g. investors/stocks and users/businesses) and edges of temporal interactions with attributes (e.g. transactions and reviews). In this paper, we study the problem of node embedding in attributed interaction graphs. Learning embeddings in interaction graphs is highly challenging due to the dynamics and heterogeneous attributes of edges. Different from conventional static graphs, in attributed interaction graphs, each edge can have totally different meanings when the interaction is at different times or associated with different attributes. We propose a deep node embedding method called IGE (Interaction Graph Embedding). IGE is composed of three neural networks: an encoding network is proposed to transform attributes into a fixed-length vector to deal with the heterogeneity of attributes; then encoded attribute vectors interact with nodes multiplicatively in two coupled prediction networks that investigate the temporal dependency by treating incident edges of a node as the analogy of a sentence in word embedding methods. The encoding network can be specifically designed for different datasets as long as it is differentiable, in which case it can be trained together with prediction networks by back-propagation. We evaluate our proposed method and various comparing methods on four real-world datasets. The experimental results prove the effectiveness of the learned embeddings by IGE on both node clustering and classification tasks. Yao Zhang 0009, Yun Xiong, Xiangnan Kong, Yangyong Zhu |
CIKM | 1 |
| 2017 | BiCycle: Item Recommendation with Life CyclesabstractRecommender systems have attracted much attention in last decades, which can help the users explore new items in many applications. As a popular technique in recommender systems, item recommendation works by recommending items to users based on their historical interactions. Conventional item recommendation methods usually assume that users and items are stationary, which is not always the case in real-world applications. Many time-aware item recommendation models have been proposed to take the temporal effects into the considerations based on the absolute time stamps associated with observed interactions. We show that using absolute time to model temporal effects can be limited in some circumstances. In this work, we propose to model the temporal dynamics of both users and items in item recommendation based on their life cycles. This problem is very challenging to solve since the users and items can co-evolve in their life cycles and the sparseness of the data become more severe when we consider the life cycles of both users and items. A novel time-aware item recommendation model called BiCycle is proposed to address these challenges. BiCycle is designed based on two important observations: 1) correlated users or items usually share similar patterns in the similar stages of their life cycles. 2) user preferences and item characters can evolve gradually over different stages of their life cycles. Extensive experiments conducted on three real-world datasets demonstrate the proposed approach can significantly improve the performance of recommendation tasks by considering the inner life cycles of both users and items. Xinyue Liu 0003, Yuanfang Song, Charu C. Aggarwal, Yao Zhang 0009, Xiangnan Kong |
ICDM | 4 |
| 2017 | Meta-Path Graphical Lasso for Learning Heterogeneous ConnectivitiesabstractSparse inverse covariance estimation has attracted lots of interests since it can recover the structure of the underlying Gaussian graphical model. This is a useful tool to demonstrate the connections among objects (nodes). Previous works on sparse inverse covariance estimation mainly focus on learning one single type of connections from the observed activities with a lasso, group lasso or tree-structure penalty. However, in many real-world applications, the observed activities on the nodes can be related to multiple types of connections. In this paper, we consider the problem of learning heterogeneous connectivities from the observed activities by incorporating meta paths extracted from a heterogeneous information network (HIN), an information network with multiple types of nodes and links, into the conventional graphical lasso framework. We aim at extracting the strongest type of relation between any pairs of entities and ignoring other minor relations. Specially, we introduce two novel kinds of constraints: meta path constraints and exclusive constraints, which ensure the unique type of relation among a pair of objects. This problem is highly challenging due to the non-convex optimization. We proposed a method based upon the alternating direction method of multipliers (ADMM) to efficiently solve the problem. The conducted experiments on both synthetic and real-world datasets illustrate the effectiveness of the proposed method. Yao Zhang 0009, Yun Xiong, Xinyue Liu 0003, Xiangnan Kong, Yangyong Zhu |
SDM | 1 |