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20212026
most citedFast Density Estimation for Density-based Clustering Methods

1 citations · 1 across the 6 of their papers we have counts for

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7 papers

cs.AI2026

Adam under Generalized Smoothness with Second-Moment-Type Stochastic Gradients

Ruinan Jin, Difei Cheng, Ling Chen +3

Adam is widely observed to remain stable even when the objective deviates significantly from global smoothness. Under the generalized smoothness framework, however, existing analys…

cs.LG2026

A Decomposition Framework for Certifiably Optimal Orthogonal Sparse PCA

Difei Cheng, Qiao Hu

Sparse Principal Component Analysis (SPCA) is an important technique for high-dimensional data analysis, improving interpretability by imposing sparsity on principal components. Ho…

cs.LG2025

Online AUC Optimization Based on Second-order Surrogate Loss

JunRu Luo, Difei Cheng, Bo Zhang

The Area Under the Curve (AUC) is an important performance metric for classification tasks, particularly in class-imbalanced scenarios. However, minimizing the AUC presents signifi…

math.OC2025

Convergence Analysis of the Last Iterate in Distributed Stochastic Gradient Descent with Momentum

Difei Cheng, Ruinan Jin, Hong Qiao +1

Distributed stochastic gradient methods are widely used to preserve data privacy and ensure scalability in large-scale learning tasks. While existing theory on distributed momentum…

cs.LG2025

Stochastic Gradient Descent in Non-Convex Problems: Asymptotic Convergence with Relaxed Step-Size via Stopping Time Methods

Ruinan Jin, Difei Cheng, Hong Qiao +3

Stochastic Gradient Descent (SGD) is widely used in machine learning research. Previous convergence analyses of SGD under the vanishing step-size setting typically require Robbins-…

cs.LG2022

Careful Seeding for k-Medois Clustering with Incremental k-Means++ Initialization

Difei Cheng, Yunfeng Zhang, Ruinan Jin

K-medoids clustering is a popular variant of k-means clustering and widely used in pattern recognition and machine learning. A main drawback of k-medoids clustering is that an impr…

cs.LG2021★ 1 cited

Fast Density Estimation for Density-based Clustering Methods

Difei Cheng, Ruihang Xu, Bo Zhang +1

Density-based clustering algorithms are widely used for discovering clusters in pattern recognition and machine learning since they can deal with non-hyperspherical clusters and ar…