← Search

Charalampos Tsourakakis

6 accepted papers

2025

Estimating Hitting Times Locally at Scale

NeurIPS 2025poster

Hitting times provide a fundamental measure of distance in random processes, quantifying the expected number of steps for a random walk starting at node $u$ to reach node $v$. They have broad applications across domains such as network centrality analysis, ranking and recommendation systems, and epi…

Cited by 0SourceScholar
2024

On the Role of Edge Dependency in Graph Generative Models

ICML 2024poster

We investigate the trade-off between the representation power of graph generative models and model *overlap*, i.e., the degree to which the model generates diverse outputs versus regurgitating its training data. In particular, we delineate a nested hierarchy of graph generative models categorized in…

Cited by 1SourcePDFScholar
2022

Practical Almost-Linear-Time Approximation Algorithms for Hybrid and Overlapping Graph Clustering

ICML 2022spotlight

Detecting communities in real-world networks and clustering similarity graphs are major data mining tasks with a wide range of applications in graph mining, collaborative filtering, and bioinformatics. In many such applications, overwhelming empirical evidence suggests that communities and clusters…

Cited by 9SourcePDFScholar
2021

DeepWalking Backwards: From Embeddings Back to Graphs

ICML 2021spotlight

Low-dimensional node embeddings play a key role in analyzing graph datasets. However, little work studies exactly what information is encoded by popular embedding methods, and how this information correlates with performance in downstream learning tasks. We tackle this question by studying whether e…

2021

On the Power of Edge Independent Graph Models

NeurIPS 2021poster

Why do many modern neural-network-based graph generative models fail to reproduce typical real-world network characteristics, such as high triangle density? In this work we study the limitations of $edge\ independent\ random\ graph\ models$, in which each edge is added to the graph independently…

2020

Node Embeddings and Exact Low-Rank Representations of Complex Networks

NeurIPS 2020poster

Low-dimensional embeddings, from classical spectral embeddings to modern neural-net-inspired methods, are a cornerstone in the modeling and analysis of complex networks. Recent work by Seshadhri et al. (PNAS 2020) suggests that such embeddings cannot capture local structure arising in complex networ…