Recommender Systems

I work on recommendation problems where user behavior, retrieval spaces, and deployment constraints change over time.

Signals, retrieval, and prediction

How can recommendation systems model returning users, retrieve efficiently, and remain reliable under industrial-scale constraints?

Scope

User reactivation, generative recommendation, Semantic-ID interface diagnostics, dynamic retrieval, graph embedding, counterfactual watch-time prediction, and efficient CTR modeling form the main technical line.

User reactivation

Recalibrating recommendation when returning users have pre-gap history but no observed behavior during long inactivity gaps.

Generative recommendation

Representing long histories, structured intent, and preference-aware generation.

Dynamic retrieval

Efficient item retrieval and graph embedding under changing user and item behavior.

Code and artifact diagnostics

Inspecting recommendation artifacts such as Semantic-ID interfaces before downstream training, refresh, and deployment.

Trustworthy prediction and efficiency

Counterfactual watch-time prediction and efficient CTR modeling for deployment.

Papers in this area

Recommender Systems

SIDScope: A Diagnostic Resource for Semantic-ID Interfaces in Generative Recommendation

J Ding, H Qin, T Wu, Y Cao arXiv 2026

Towards Practical Large-scale Dynamic Heterogeneous Graph Embedding: Cold-start Resilient Recommendation

M Long, J Liu, Y Li, H Xiong, J Yan, K Wang, Y Cao, J Ding TKDE 2026

Personalized Task Dependency Graphs for Mitigating Signal Erosion in Multi-Task Recommendation

F Liu, T Wu, Y Fang, W Zhou, Z Zhou, W Chen, Q Mei, J Zhou, H Chang, Y Cao, J Ding CIKM 2026

SIDInspector: A Mapping-First Diagnostic Resource for Semantic-ID Tokenizers

J Ding, H Chang, H Qin, T Liu CIKM 2026

Zero-Observation User Reactivation with Gap-Driven Dimensional Gating

J Ding, T Liu, F Liu, H Qin, T Wu RecSys 2026

Beyond the Flat Sequence: Hierarchical and Preference-Aware Generative Recommendations

Z Chen, H Chang, T Liu, C Zhou, Y Cao, J Ding, M Liu, B Qin WWW 2026

Invariant feature learning for counterfactual watch-time prediction in video recommendation

C Jin, Y Ren, H Ma, Y Xia, Y Guan, H Zhang, J Ding, J Guan, S Zhou AAAI 2026

RPE4Rec: Enhancing Dynamic Node Retrieval with Efficient Relative Position Encoding for Recommendation Systems

K Cheng, H Chang, P Wang, L Gu, J Ding, Y Cao, J Ye, B Du WSDM 2026

Unified Low-rank Compression Framework for Click-through Rate Prediction

H Yu, M Fu, J Ding, Y Zhou, J Wu KDD 2024

Related patents

Patents

Method and device for recommending playing time of video playing platform and electronic equipment

CN-115080791-A 2022 / Recommendation and user modeling
CN Application