activity
20202024
most citedA Critical Study on Data Leakage in Recommender System Offline Evaluation

82 citations · 141 across the 5 of their papers we have counts for

collaborators

6 papers

cs.IR2024

Hesitation and Tolerance in Recommender Systems

Kuan Zou, Aixin Sun, Yitong Ji +5

Users' interactions with recommender systems often involve more than simple acceptance or rejection. We highlight two overlooked states: hesitation, when people deliberate without…

cs.IR2023★ 1 cited

Our Model Achieves Excellent Performance on MovieLens: What Does it Mean?

Yu-chen Fan, Yitong Ji, Jie Zhang +1

A typical benchmark dataset for recommender system (RecSys) evaluation consists of user-item interactions generated on a platform within a time period. The interaction generation m…

cs.IR2023★ 1 cited

Retraining A Graph-based Recommender with Interests Disentanglement

Yitong Ji, Aixin Sun, Jie Zhang

In a practical recommender system, new interactions are continuously observed. Some interactions are expected, because they largely follow users' long-term preferences. Some other…

cs.IR2022★ 3 cited

Do Loyal Users Enjoy Better Recommendations? Understanding Recommender Accuracy from a Time Perspective

Yitong Ji, Aixin Sun, Jie Zhang +1

In academic research, recommender systems are often evaluated on benchmark datasets, without much consideration about the global timeline. Hence, we are unable to answer questions…

cs.IR2020★ 82 cited

A Critical Study on Data Leakage in Recommender System Offline Evaluation

Yitong Ji, Aixin Sun, Jie Zhang +1

Recommender models are hard to evaluate, particularly under offline setting. In this paper, we provide a comprehensive and critical analysis of the data leakage issue in recommende…

cs.IR2020★ 54 cited

A Re-visit of the Popularity Baseline in Recommender Systems

Yitong Ji, Aixin Sun, Jie Zhang +1

Popularity is often included in experimental evaluation to provide a reference performance for a recommendation task. To understand how popularity baseline is defined and evaluated…