Bad local minima exist in the stochastic block model

Fuente: arXiv
Salvato in:
Dettagli Bibliografici
Autori principali: Coja-Oghlan, Amin, Krieg, Lena, Lawnik, Johannes Christian, Scheftelowitsch, Olga
Natura: Preprint
Pubblicazione: 2024
Soggetti:
Accesso online:
Tags: Aggiungi Tag
Nessun Tag, puoi essere il primo ad aggiungerne!!
_version_ 1866914886624215040
author Coja-Oghlan, Amin
Krieg, Lena
Lawnik, Johannes Christian
Scheftelowitsch, Olga
author_facet Coja-Oghlan, Amin
Krieg, Lena
Lawnik, Johannes Christian
Scheftelowitsch, Olga
contents We study the disassortative stochastic block model with three communities, a well-studied model of graph partitioning and Bayesian inference for which detailed predictions based on the cavity method exist [Decelle et al. (2011)]. We provide strong evidence that for a part of the phase where efficient algorithms exist that approximately reconstruct the communities, inference based on maximum a posteriori (MAP) fails. In other words, we show that there exist modes of the posterior distribution that have a vanishing agreement with the ground truth. The proof is based on the analysis of a graph colouring algorithm from [Achlioptas and Moore (2003)].
format Preprint
id arxiv_https___arxiv_org_abs_2407_17851
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle Bad local minima exist in the stochastic block model
Coja-Oghlan, Amin
Krieg, Lena
Lawnik, Johannes Christian
Scheftelowitsch, Olga
Statistics Theory
Discrete Mathematics
Information Theory
Mathematical Physics
Probability
05C80 (Primary) 62B10, 68R10 (Secondary)
We study the disassortative stochastic block model with three communities, a well-studied model of graph partitioning and Bayesian inference for which detailed predictions based on the cavity method exist [Decelle et al. (2011)]. We provide strong evidence that for a part of the phase where efficient algorithms exist that approximately reconstruct the communities, inference based on maximum a posteriori (MAP) fails. In other words, we show that there exist modes of the posterior distribution that have a vanishing agreement with the ground truth. The proof is based on the analysis of a graph colouring algorithm from [Achlioptas and Moore (2003)].
title Bad local minima exist in the stochastic block model
topic Statistics Theory
Discrete Mathematics
Information Theory
Mathematical Physics
Probability
05C80 (Primary) 62B10, 68R10 (Secondary)
url https://arxiv.org/abs/2407.17851