arXiv Machine Learning

Variational Estimators for Node Popularity Models

The paper introduces a variational expectation‑maximization (VEM) framework for estimating node popularity in bipartite networks, specifically targeting the Two‑Way Node Popularity Model (TNPM). It demonstrates label consistency for community assignments and shows through simulations that the method outperforms existing algorithms in both bipartite and undirected networks. Real‑world experiments confirm the approach’s practical effectiveness and robustness.

arXiv Machine Learning
Oct 23

Optimal Clustering of Multi-layer Networks under Mixture Block Models

The paper investigates clustering of multi‑layer networks generated under a mixture multi‑layer stochastic block model (MMSBM). It derives the minimax optimal clustering error rate, expressed via Chernoff information between component edge‑probability distributions, and introduces a two‑stage estimator that achieves this rate even under extreme sparsity. The method is extended to count‑weighted networks using a mixture multi‑layer Poisson block model, with numerical experiments and real‑data analyses demonstrating its practical performance.

By Zhongyuan Lyu, Ting Li, Dong Xia
arXiv Machine Learning
Oct 3

Degree-Corrected Joint Matrix Factorization for Multilayer Community Detection

The paper introduces a degree‑corrected joint matrix factorization technique for detecting communities in multilayer networks. It uses a nonnegative symmetric matrix trifactorization that enforces disjoint, shared communities across layers while allowing each layer to have distinct connectivity patterns and node degrees. An efficient algorithm is presented and evaluated on a multilayer degree‑corrected stochastic block model, showing superior performance compared to existing methods.

By Alexandra Dache, Manon Rustin, Arnaud Vandaele, Nicolas Gillis
arXiv Machine Learning
Aug 12

Stay or Stray - A Dynamical Systems Viewpoint of Popularity Bias

arXiv:2608. 10474v1 Announce Type: cross Abstract: Popularity bias in recommendation systems arises when a majority user class generates disproportionate interaction data, causing the system to increasingly favour it while degrading recommendation quality for niche users.

By Sarvesh Shashidhar, Lankireddy Prabhat, Arpit Agarwal, D. Manjunath, Karan Bhukar, Tanmay Khandelwal
arXiv AI
Sep 10

LLMs for Social Network Modeling: From Network Generation to Dynamic Processes

The paper reviews how large language models (LLMs) are being used to model social networks, highlighting their ability to represent users, relationships, and interactions through natural language. It categorizes existing work into network generative models—split into selection‑based and interaction‑based approaches—and dynamic process models, which cover opinion dynamics, information diffusion, and rumor propagation. The survey also discusses the advantages of LLMs for realistic, context‑aware social behavior, while noting limitations such as social biases and prompt sensitivity, and outlines open research challenges and future directions.

By Shikha Mallick, Alex Thomo, Akrati Saxena