EDBT 2026 Demo / reviewers in the wild / expert
Hongjun Wang 0007
dblp:65/3627-7
· DBLP profile ↗
22ranked-venue papers
11as first author
22since 2021 · last 2026
0000-0002-5396-7659ORCID · conflict
Domains — the database's venue-derived domains; a paper can count in several
Artificial intelligence and machine learning · 10 · 6 first-author · 10 since 2021Graphics, computer vision, multimedia, augmented reality and games · 8 · 5 first-author · 8 since 2021Databases, data management, data science and information retrieval · 6 · 3 first-author · 6 since 2021Computer networks · 5 · 2 first-author · 5 since 2021Applied, interdisciplinary, general and emerging computing · 2 · 1 first-author · 2 since 2021
| Year | Publication | Venue | Position |
|---|---|---|---|
| 2026 | Resilience Inference for Supply Chains with Hypergraph Neural NetworkabstractSupply chains are integral to global economic stability, yet disruptions can swiftly propagate through interconnected networks, resulting in substantial economic impacts. Accurate and timely inference of supply chain resilience—the capability to maintain core functions during disruptions—is crucial for proactive risk mitigation and robust network design. However, existing approaches lack effective mechanisms to infer supply chain resilience without explicit system dynamics and struggle to represent the higher-order, multi-entity dependencies inherent in supply chain networks. These limitations motivate the definition of a novel problem and the development of targeted modeling solutions. To address these challenges, we formalize a novel problem: Supply Chain Resilience Inference (SCRI), defined as predicting supply chain resilience using hypergraph topology and observed inventory trajectories without explicit dynamic equations. To solve this problem, we propose the Supply Chain Resilience Inference Hypergraph Network (SC-RIHN), a novel hypergraph-based model leveraging set-based encoding and hypergraph message passing to capture multi-party firm-product interactions. Comprehensive experiments demonstrate that SC-RIHN significantly outperforms traditional MLP, representative graph neural network variants, and ResInf baselines across synthetic benchmarks, underscoring its potential for practical, early-warning risk assessment in complex supply chain systems. Zetian Shen, Hongjun Wang 0007, Jiyuan Chen, Xuan Song 0001 |
AAAI | 2 |
| 2026 | HarmoQ: Harmonized Post-Training Quantization for High-Fidelity Image Super-ResolutionabstractPost-training quantization offers an efficient pathway to deploy super-resolution models, yet existing methods treat weight and activation quantization independently, missing their critical interplay. Through controlled experiments on SwinIR, we uncover a striking asymmetry: weight quantization primarily degrades structural similarity, while activation quantization disproportionately affects pixel-level accuracy. This stems from their distinct roles—weights encode learned restoration priors for textures and edges, whereas activations carry input-specific intensity information. Building on this insight, we propose HarmoQ, a unified framework that harmonizes quantization across components through three synergistic steps: structural residual calibration proactively adjusts weights to compensate for activation-induced detail loss, harmonized scale optimization analytically balances quantization difficulty via closed-form solutions, and adaptive boundary refinement iteratively maintains this balance during optimization. Experiments show HarmoQ achieves substantial gains under aggressive compression, outperforming prior art by 0.46 dB on Set5 at 2-bit while delivering 3.2× speedup and 4× memory reduction on A100 GPUs. This work provides the first systematic analysis of weight-activation coupling in super-resolution quantization and establishes a principled solution for efficient high-quality image restoration. Hongjun Wang 0007, Jiyuan Chen, Xuan Song 0001, Yinqiang Zheng |
AAAI | 1 |
| 2026 | Towards Resilient Transportation: A Conditional Transformer for Accident-Informed Traffic ForecastingabstractTraffic prediction remains a key challenge in spatio-temporal data mining, despite progress in deep learning. Accurate forecasting is hindered by the complex influence of external factors such as traffic accidents and regulations, often overlooked by existing models due to limited data integration. To address these limitations, we present two enriched traffic datasets from Tokyo and California, incorporating traffic accident and regulation data. Leveraging these datasets, we propose ConFormer (Conditional Transformer), a novel framework that integrates graph propagation with guided normalization layer. This design dynamically adjusts spatial and temporal node relationships based on historical patterns, enhancing predictive accuracy. Our model surpasses the state-of-the-art STAEFormer in both predictive performance and efficiency, achieving lower computational costs and reduced parameter demands. Extensive evaluations demonstrate that ConFormer consistently outperforms mainstream spatio-temporal baselines across multiple metrics, underscoring its potential to advance traffic prediction research. The code is released in https://github.com/Dreamzz5/ConFormer. Hongjun Wang 0007, Jiawei Yong, Jiawei Wang 0005, Shintaro Fukushima, Renhe Jiang |
KDD (1) | 1 |
| 2026 | Taming Spatial Heterophily and Temporal Irregularity: A Curriculum Learning Approach for Traffic Forecasting
Hongjun Wang 0007, Zhiwen Zhang 0004, Jiyuan Chen, Zipei Fan, Renhe Jiang, Wei Yuan 0004, Ryosuke Shibasaki, Xuan Song 0001 |
IEEE Trans. Intell. Transp. Syst. | 1 |
| 2026 | MobileLLM: Semantic-Enhanced Large Language Model for Multimodal Cellular Traffic Prediction in Urban NetworksabstractThe rapid densification of 5G deployments and the emergence of 6G-era services demand accurate cellular traffic forecasting across heterogeneous communication modalities at fine spatiotemporal resolutions. Existing approaches primarily rely on numerical time-series analysis and often underutilize contextual information related to urban function, temporal routines, and external events. This paper presents MobileLLM, a dual-pathway framework that integrates numerical spatiotemporal signals with semantic contextual conditioning for multimodal cellular traffic prediction. The numerical pathway encodes historical traffic observations into node-level tokens, while the semantic pathway transforms structured contextual descriptions into text embeddings. These pathways are fused through a partially frozen GPT-2 backbone and a cross-modal decoder, enabling parameter-efficient adaptation while preserving useful pre-trained priors. Rather than using language models for raw numerical regression, our framework uses the semantic pathway to provide context-aware conditioning for numerical forecasting. Comprehensive evaluation on three real-world datasets-Milan, Trentino, and Shanghai-demonstrates consistent performance improvements across SMS, voice call, and Internet traffic prediction. MobileLLM achieves MAE improvements ranging from 0.88% to 32.62% over strong baselines, with particularly pronounced gains for Internet traffic where contextual dependence is strongest. These results show that combining numerical modeling with semantic contextual representations provides a practical and effective direction for next-generation cellular traffic forecasting. Hongjun Wang 0007, Jiyuan Chen, Xuan Song 0001 |
IEEE Trans. Mob. Comput. | 1 |
| 2026 | Tiered Spatio-Temporal Difficulty: Curriculum Scheduler for Multi-Sensor Traffic Flow PredictionabstractThe development of the Internet of Things (IoT) has enhanced smart city services for traffic monitoring, leading to numerous schemes for accurate flow prediction based on traffic sensors. However, existing approaches primarily capture spatio-temporal (ST) dependencies from traffic graphs and train their models using randomly ordered data. This overlooks the fact that the modeling difficulty of each sensor/node in the ST traffic graph can vary significantly due to its spatial dependencies and temporal trends, resulting in unreliable and unstable predictions in IoT scenarios. In this context, we argue that a well-designed curriculum with an easy-to-difficult order can improve the training of ST models. Therefore, this paper introduces an ST difficulty measurer to score the node-level difficulty of traffic graph from both spatial and temporal aspects, and then implements a curriculum in the ST model training process. More specifically, based on the tiered ST difficulty score, the ST model training begins with a subgraph consisting of “easy” nodes characterized by relatively consistent spatial relationships and regular temporal patterns. Gradually, more difficult nodes are incorporated into the subgraph and participate in subsequent training stages. Comprehensive experiments and analysis on two real-world traffic flow datasets confirm the effectiveness of our proposed approach. Zhiwen Zhang 0004, Hongjun Wang 0007, Zipei Fan, Renhe Jiang, Wei Yuan 0004, Xuan Song 0001, Ryosuke Shibasaki |
IEEE Trans. Mob. Comput. | 2 |
| 2025 | Not All Degradations are Equal: A Targeted Feature Denoising Framework for Generalizable Image Super-ResolutionabstractGeneralizable Image Super-Resolution aims to enhance model generalization capabilities under unknown degradations. To achieve this goal, the models are expected to focus only on image content-related features instead of overfitting degradations. Recently, numerous approaches such as Dropout and Feature Alignment have been proposed to suppress models' natural tendency to overfit degradations and yield promising results. Nevertheless, these works have assumed that models overfit to all degradation types (e.g., blur, noise, JPEG), while through careful investigations in this paper, we discover that models predominantly overfit to noise, largely attributable to its distinct degradation pattern compared to other degradation types. In this paper, we propose a targeted feature denoising framework, comprising noise detection and denoising modules. Our approach presents a general solution that can be seamlessly integrated with existing super-resolution models without requiring architectural modifications. Our framework demonstrates superior performance compared to previous regularization-based methods across five traditional benchmarks and datasets, encompassing both synthetic and real-world scenarios. Hongjun Wang 0007, Jiyuan Chen, Zhengwei Yin, Xuan Song 0001, Yinqiang Zheng |
ICCV | 1 |
| 2025 | Random Is All You Need: Random Noise Injection on Feature Statistics for Generalizable Deep Image DenoisingabstractRecent advancements in generalizable deep image denoising have catalyzed the development of robust noise-handling models. The current state-of-the-art, Masked Training (MT), constructs a masked swinir model which is trained exclusively on Gaussian noise ($\sigma$=15) but can achieve commendable denoising performance across various noise types (*i.e.* speckle noise, poisson noise). However, this method, while focusing on content reconstruction, often produces over-smoothed images and poses challenges in mask ratio optimization, complicating its integration with other methodologies. In response, this paper introduces RNINet, a novel architecture built on a streamlined encoder-decoder framework to enhance both efficiency and overall performance. Initially, we train a pure RNINet (only simple encoder-decoder) on individual noise types, observing that feature statistics such as mean and variance shift in response to different noise conditions. Leveraging these insights, we incorporate a noise injection block that injects random noise into feature statistics within our framework, significantly improving generalization across unseen noise types. Our framework not only simplifies the architectural complexity found in MT but also delivers superior performance. Comprehensive experimental evaluations demonstrate that our method outperforms MT in various unseen noise conditions in terms of denoising effectiveness and computational efficiency (lower MACs and GPU memory usage), achieving up to 10 times faster inference speeds and underscoring it's capability for large scale deployments. Zhengwei Yin, Hongjun Wang 0007, Guixu Lin, Weihang Ran, Yinqiang Zheng |
ICLR | 2 |
| 2025 | Assessing the Spatial-Temporal Causal Impact of COVID-19-Related Policies on Epidemic SpreadabstractAnalyzing the causal impact of various government-related policies on the epidemic spread is of critical importance. This article aims to investigate the problem of assessing the causal effects of different COVID-19-related policies on the USA epidemic spread in different counties at any given time period, while eliminating biased interference from unobserved confounders (e.g., the vigilance of residents). However, the infection outcome of each region is influenced not only by its own confounding factors but also by policy interventions implemented in neighboring regions. Furthermore, the government policy index may exhibit a time-delay influence on outbreak dynamics. To this end, we implement observational data about different COVID-19-related policies (treatment) and outbreak dynamics (outcome) across different U.S. counties over time and develop a causal framework that learns the representations of time-varying confounders to tackle the aforementioned issues. More specifically, we employ one recurrent structure to capture the accumulative effects stemming from the policy history and then utilize hypergraph neural network to model the interactions among spatial regions. Our experimental results demonstrate the effectiveness of the proposed framework in quantifying the causal impact of different policy types on epidemics. Compared with baseline methods, our assessment provides valuable insights for future policy-making endeavors. Zhiwen Zhang 0004, Hongjun Wang 0007, Zipei Fan, Xuan Song 0001, Ryosuke Shibasaki |
ACM Trans. Knowl. Discov. Data | 2 |
| 2025 | Evaluating the Generalization Ability of Spatiotemporal Model in Urban ScenarioabstractSpatiotemporal neural networks have shown great promise in urban scenarios by effectively capturing temporal and spatial correlations. However, urban environments are constantly evolving, and current model evaluations are often limited to traffic scenarios and use data mainly collected only a few weeks after training period to evaluate model performance. The generalization ability of these models remains largely unexplored. To address this, we propose a Spatiotemporal Out-of-Distribution (ST-OOD) benchmark, which comprises six urban scenario: bike-sharing, 311 services, pedestrian counts, traffic speed, traffic flow, ride-hailing demand, and bike-sharing, each with in-distribution (same year) and out-of-distribution (next years) settings. We extensively evaluate state-of-the-art spatiotemporal models and find that their performance degrades significantly in out-of-distribution settings, with most models performing even worse than a simple Multi-Layer Perceptron (MLP). Our findings suggest that current leading methods tend to over-rely on parameters to overfit training data, which may lead to good performance on in-distribution data but often results in poor generalization. We also investigated whether dropout could mitigate the negative effects of overfitting. Our results showed that a slight dropout rate could significantly improve generalization performance on most datasets, with minimal impact on in-distribution performance. However, balancing in-distribution and out-of-distribution performance remains a challenging problem. We hope that the proposed benchmark will encourage further research on this critical issue. Hongjun Wang 0007, Jiyuan Chen, Tong Pan, Zheng Dong 0006, Renhe Jiang, Xuan Song 0001 |
IEEE Trans. Mob. Comput. | 1 |
| 2024 | Navigating Beyond Dropout: An Intriguing Solution Towards Generalizable Image Super ResolutionabstractDeep learning has led to a dramatic leap on Single Image Super-Resolution (SISR) performances in recent years. While most existing work assumes a simple and fixed degradation model (e.g., bicubic downsampling), the research of Blind SR seeks to improve model generalization ability with unknown degradation. Recently, Kong et al. [37] pioneer the investigation of a more suitable training strategy for Blind SR using Dropout [63]. Although such method indeed brings substantial generalization improvements via mitigating overfitting, we argue that Dropout simultaneously introduces undesirable side-effect that compromises model's capacity to faithfully reconstruct fine details. We show both the theoretical and experimental analyses in our paper, and furthermore, we present another easy yet effective training strategy that enhances the generalization ability of the model by simply modulating its first and second-order features statistics. Experimental results have shown that our method could serve as a model-agnostic regularization and outperforms Dropout on seven benchmark datasets including both synthetic and real-world scenarios. Hongjun Wang 0007, Jiyuan Chen, Yinqiang Zheng, Tieyong Zeng |
CVPR | 1 |
| 2024 | TrafPS: A shapley-based visual analytics approach to interpret trafficabstractRecent achievements in deep learning (DL) have demonstrated its potential in predicting traffic flows. Such predictions are beneficial for understanding the situation and making traffic control decisions. However, most state-of-the-art DL models are considered “black boxes” with little to no transparency of the underlying mechanisms for end users. Some previous studies attempted to “open the black box” and increase the interpretability of generated predictions. However, handling complex models on large-scale spatiotemporal data and discovering salient spatial and temporal patterns that significantly influence traffic flow remain challenging. To overcome these challenges, we present TrafPS , a visual analytics approach for interpreting traffic prediction outcomes to support decision-making in traffic management and urban planning. The measurements region SHAP and trajectory SHAP are proposed to quantify the impact of flow patterns on urban traffic at different levels. Based on the task requirements from domain experts, we employed an interactive visual interface for the multi-aspect exploration and analysis of significant flow patterns. Two real-world case studies demonstrate the effectiveness of TrafPS in identifying key routes and providing decision-making support for urban planning. Zezheng Feng, Hongjun Wang 0007, Zipei Fan, Shuang-Hua Yang, Huamin Qu, Xuan Song 0001 |
Comput. Vis. Media | 3 |
| 2024 | HoLens: A visual analytics design for higher-order movement modeling and visualizationabstractHigher-order patterns reveal sequential multistep state transitions, which are usually superior to origin-destination analyses that depict only first-order geospatial movement patterns. Conventional methods for higher-order movement modeling first construct a directed acyclic graph (DAG) of movements and then extract higher-order patterns from the DAG. However, DAG-based methods rely heavily on identifying movement keypoints, which are challenging for sparse movements and fail to consider the temporal variants critical for movements in urban environments. To overcome these limitations, we propose HoLens, a novel approach for modeling and visualizing higher-order movement patterns in the context of an urban environment. HoLens mainly makes twofold contributions: First, we designed an auto-adaptive movement aggregation algorithm that self-organizes movements hierarchically by considering spatial proximity, contextual information, and temporal variability. Second, we developed an interactive visual analytics interface comprising well-established visualization techniques, including the H-Flow for visualizing the higher-order patterns on the map and the higher-order state sequence chart for representing the higher-order state transitions. Two real-world case studies demonstrate that the method can adaptively aggregate data and exhibit the process of exploring higher-order patterns using HoLens. We also demonstrate the feasibility, usability, and effectiveness of our approach through expert interviews with three domain experts. Zezheng Feng, Hongjun Wang 0007, Jianing Hao, Shuang-Hua Yang, Wei Zeng 0004, Huamin Qu |
Comput. Vis. Media | 3 |
| 2023 | Easy Begun Is Half Done: Spatial-Temporal Graph Modeling with ST-Curriculum DropoutabstractSpatial-temporal (ST) graph modeling, such as traffic speed forecasting and taxi demand prediction, is an important task in deep learning area. However, for the nodes in the graph, their ST patterns can vary greatly in difficulties for modeling, owning to the heterogeneous nature of ST data. We argue that unveiling the nodes to the model in a meaningful order, from easy to complex, can provide performance improvements over traditional training procedure. The idea has its root in Curriculum Learning, which suggests in the early stage of training models can be sensitive to noise and difficult samples. In this paper, we propose ST-Curriculum Dropout, a novel and easy-to-implement strategy for spatial-temporal graph modeling. Specifically, we evaluate the learning difficulty of each node in high-level feature space and drop those difficult ones out to ensure the model only needs to handle fundamental ST relations at the beginning, before gradually moving to hard ones. Our strategy can be applied to any canonical deep learning architecture without extra trainable parameters, and extensive experiments on a wide range of datasets are conducted to illustrate that, by controlling the difficulty level of ST relations as the training progresses, the model is able to capture better representation of the data and thus yields better generalization. Hongjun Wang 0007, Jiyuan Chen, Tong Pan, Zipei Fan, Xuan Song 0001, Renhe Jiang, Lingyu Zhang 0001, Boyuan Zhang 0005 |
AAAI | 1 |
| 2023 | Assessing the Continuous Causal Responses of Typhoon-related Weather on Human Mobility: An Empirical Study in JapanabstractTo understand human mobility following the typhoon, analyzing the causal impact of extreme typhoon weather on human mobility is important for disaster emergency management. However, the unobserved confounders (e.g., the characteristic of each region) correlate with the strength of typhoon weather and also affect human mobility during typhoon, which may generate biased influences on the causal analysis process. Besides, these confounders may be time-varying following the dynamic movements of typhoon. In this work, we develop a neural network-based continuous causal effect estimation framework to mitigate the interference from (unobserved) confounders and assess the continuous causal responses of typhoon-related weather (treatment) on several types of human mobility (outcome) across different counties at any given period. To this end, we integrate the big data from two huge typhoons in Japan (i.e., Typhoon Faxai and Hagibis) and leverage multiple sources of covariates (i.e., residents' vigilance and basic mobility patterns) from different counties to learn the representations of time-varying confounders. The experimental results indicate the effectiveness of our proposed framework in capturing the confounders for quantifying the causal impact of extreme weather during the typhoon process, compared with several existing causal studies. Zhiwen Zhang 0004, Hongjun Wang 0007, Zipei Fan, Ryosuke Shibasaki, Xuan Song 0001 |
CIKM | 2 |
| 2023 | Causal-Based Supervision of Attention in Graph Neural Network: A Better and Simpler Choice towards Powerful AttentionabstractRecent years have witnessed the great potential of attention mechanism in graph representation learning. However, while variants of attention-based GNNs are setting new benchmarks for numerous real-world datasets, recent works have pointed out that their induced attentions are less robust and generalizable against noisy graphs due to lack of direct supervision. In this paper, we present a new framework which utilizes the tool of causality to provide a powerful supervision signal for the learning process of attention functions. Specifically, we estimate the direct causal effect of attention to the final prediction, and then maximize such effect to guide attention attending to more meaningful neighbors. Our method can serve as a plug-and-play module for any canonical attention-based GNNs in an end-to-end fashion. Extensive experiments on a wide range of benchmark datasets illustrated that, by directly supervising attention functions, the model is able to converge faster with a clearer decision boundary, and thus yields better performances. Hongjun Wang 0007, Jiyuan Chen, Lun Du, Qiang Fu 0015, Shi Han, Xuan Song 0001 |
IJCAI | 1 |
| 2023 | Missing Road Condition Imputation Using a Multi-View Heterogeneous Graph Network From GPS TrajectoryabstractHow to generate road conditions from urban GPS trajectory is an important problem in transportation systems. However, this computation process usually suffers from serious missing value problem due to the observation uncertainty or limited reports from crowdsourcing systems. Conventional tensor factorization approaches learn the spatio-temporal dependencies in a collaborative filtering way, which ignores the complex road network structure information and temporal heterogeneity. In this study, we propose a multi-view model with multiple aspects of prior knowledge to impute traffic state computed from a real-world trajectory dataset. More specifically, in the spatial view, rather than focusing on a specific type of road segment, we take the heterogeneity of road network into consideration and model the multiple relations of adjacent road segments. Meanwhile, the temporal pattern is also viewed as a heterogeneous graphical structure that discriminates the weekly/hourly adjacency in the temporal view. Finally, we fuse the above spatio-temporal features to provide a robust estimation under different sparse conditions. Intensive experiments on two types of missing scenarios (i.e., random and non-random) demonstrate that the proposed imputation method outperforms all the other state-of-the-art approaches. In addition, our model represents interpretable patterns for spatio-temporal graph analysis. Zhiwen Zhang 0004, Hongjun Wang 0007, Zipei Fan, Xuan Song 0001, Ryosuke Shibasaki |
IEEE Trans. Intell. Transp. Syst. | 2 |
| 2023 | ST-ExpertNet: A Deep Expert Framework for Traffic PredictionabstractRecently, forecasting the crowd flows has become an important research topic, and plentiful technologies have achieved good performances. As we all know, the flow at a citywide level is in a mixed state with several basic patterns (e.g., commuting, working, and commercial) caused by the city area functional distributions (e.g., developed commercial areas, educational areas and parks). However, existing technologies have been criticized for their lack of considering the differences in the flow patterns among regions since they want to build only one comprehensive model to learn the mixed flow tensors. Recognizing this limitation, we present a new perspective on flow prediction and propose an explainable framework named ST-ExpertNet, which can adopt every spatial-temporal model and train a set of functional experts devoted to specific flow patterns. Technically, we train a bunch of experts based on the Mixture of Experts (MoE), which guides each expert to specialize in different kinds of flow patterns in sample spaces by using the gating network. We define several criteria, including comprehensiveness, sparsity, and preciseness, to construct the experts for better interpretability and performances. We conduct experiments on a wide range of real-world taxi and bike datasets in Beijing and NYC. The visualizations of the expert's intermediate results demonstrate that our ST-ExpertNet successfully disentangles the city's mixed flow tensors along with the city layout, e.g., the urban ring road structure. Different network architectures, such as ST-ResNet, ConvLSTM, and CNN, have been adopted into our ST-ExpertNet framework for experiments and the results demonstrates the superiority of our framework in both interpretability and performances. Hongjun Wang 0007, Jiyuan Chen, Zipei Fan, Zhiwen Zhang 0004, Zekun Cai, Xuan Song 0001 |
IEEE Trans. Knowl. Data Eng. | 1 |
| 2023 | Multi-Task Weakly Supervised Learning for Origin-Destination Travel Time EstimationabstractTravel time estimation from GPS trips is of great importance to order duration, ridesharing, taxi dispatching, etc. However, the dense trajectory is not always available due to the limitation of data privacy and acquisition, while the origin-destination (OD) type of data, such as NYC taxi data, NYC bike data, and Capital Bikeshare data, is more accessible. To address this issue, this paper starts to estimate the OD trips travel time combined with the road network. Subsequently, aMulti-taskWeaklySupervisedLearning Framework forTravelTimeEstimation (MWSL-TTE) has been proposed to infer transition probability between roads segments, and the travel time on road segments and intersection simultaneously. Technically, given an OD pair, the transition probability intends to recover the most possible route. And then, the output of travel time is equal to the summation of all segments’ and intersections’ travel time in this route. A novel route recovery function has been proposed to iteratively maximize the current routes’ co-occurrence probability, and minimize the discrepancy between routes’ probability distribution and the inverse distribution of routes’ estimation loss. Moreover, the expected log-likelihood function based on a weakly-supervised framework has been deployed in optimizing the travel time from road segments and intersections concurrently. We conduct experiments on a wide range of real-world taxi datasets in Xi’an and Chengdu and demonstrate our method's effectiveness on route recovery and travel time estimation. Hongjun Wang 0007, Zhiwen Zhang 0004, Zipei Fan, Jiyuan Chen, Lingyu Zhang 0001, Ryosuke Shibasaki, Xuan Song 0001 |
IEEE Trans. Knowl. Data Eng. | 1 |
| 2022 | Route to Time and Time to Route: Travel Time Estimation from Sparse Trajectories
Zhiwen Zhang 0004, Hongjun Wang 0007, Zipei Fan, Jiyuan Chen, Xuan Song 0001, Ryosuke Shibasaki |
ECML/PKDD (6) | 2 |
| 2022 | Generative Personalized Federated Learning Framework for Travel Time EstimationabstractEstimating the travel time of a given path is an important topic for the intelligent transportation system and serves as the foundation for various real-world applications. However, building an estimation model for such a data-driven task requires a large amount of mobile users' trajectory data which directly relates to their privacy and thus is less likely to be shared. Therefore, we propose GPF-TTE, Generative Personalized Federated Learning Framework for Travel Time Estimation (poster version of our previous work [1]) based on the issue of privacy protection for the mobile user group, in which 1) utilizes the federated learning approach, allowing private data to be kept on client devices while training, 2) apart from sharing a base model, we also adapt a fine-tuned personalized model for each client to study their personal driving habits, making up for the residual error caused by the prediction of the localized global model (the base model in local device), and 3) the cloud server aggregates localized models into the global model as a generative model to infer the future road traffic state. Zipei Fan, Zhiwen Zhang 0004, Hongjun Wang 0007 |
SenSys | 3 |
| 2022 | GOF-TTE: Generative Online Federated Learning Framework for Travel Time EstimationabstractEstimating the travel time of a path is an essential topic for the intelligent transportation system. It serves as the foundation for real-world applications, such as traffic monitoring, route planning, and taxi dispatching. However, building a model for such a data-driven task requires a large amount of users’ travel information, which closely relates to their privacy and, thus, is less likely to be shared. The not independent and identically distributed (Non-IID) trajectory data across data owners also make a predictive model extremely challenging to be personalized if we directly apply federated learning. Finally, previous work on travel time estimation (TTE) does not consider the real-time traffic state of roads, which we argue, can significantly influence the prediction. To address the above challenges, we introduce GOF-TTE for the mobile user group, generative online federated learning framework for TTE, which 1) utilizes the federated learning approach, allowing private data to be kept on client devices while training, and designs the global model as an online generative model shared by all clients to infer the real-time road traffic state and 2) apart from sharing a base model at the server, adapts a fine-tuned personalized model for every client to study their personal driving habits, making up for the residual error made by localized global model prediction. We also employ a simple privacy attack to our framework and implement the differential privacy mechanism to guarantee privacy safety further. Finally, we conduct experiments on two real-world public taxi data sets of DiDi Chengdu and Xi’an. The experimental results demonstrate the effectiveness of our proposed framework. Zhiwen Zhang 0004, Hongjun Wang 0007, Zipei Fan, Jiyuan Chen, Xuan Song 0001, Ryosuke Shibasaki |
IEEE Internet Things J. | 2 |