Non-Convex Joint Community Detection and Group Synchronization via Generalized Power Method

Sijin Chen, Xiwei Cheng, Anthony Man-Cho So
Proceedings of The 27th International Conference on Artificial Intelligence and Statistics, PMLR 238:2899-2907, 2024.

Abstract

This paper proposes a Generalized Power Method (GPM) to simultaneously solve the joint problem of community detection and group synchronization in a direct non-convex manner, in contrast to the existing method of semidefinite programming (SDP). Under a natural extension of stochastic block model (SBM), our theoretical analysis proves that the proposed algorithm is able to exactly recover the ground truth in O(nlog2n) time for problems of size n, sharply outperforming the O(n3.5) runtime of SDP. Moreover, we give a lower bound of model parameters as a sufficient condition for the exact recovery of GPM. The new bound breaches the information-theoretic limit for pure community detection under SBM, thus demonstrating the superiority of our simultaneous optimization algorithm over any two-stage method that performs the two tasks in succession. We also conduct numerical experiments on GPM and SDP to corroborate our theoretical analysis.

Cite this Paper


BibTeX
@InProceedings{pmlr-v238-chen24e, title = {Non-Convex Joint Community Detection and Group Synchronization via Generalized Power Method}, author = {Chen, Sijin and Cheng, Xiwei and Man-Cho So, Anthony}, booktitle = {Proceedings of The 27th International Conference on Artificial Intelligence and Statistics}, pages = {2899--2907}, year = {2024}, editor = {Dasgupta, Sanjoy and Mandt, Stephan and Li, Yingzhen}, volume = {238}, series = {Proceedings of Machine Learning Research}, month = {02--04 May}, publisher = {PMLR}, pdf = {https://proceedings.mlr.press/v238/chen24e/chen24e.pdf}, url = {https://proceedings.mlr.press/v238/chen24e.html}, abstract = {This paper proposes a Generalized Power Method (GPM) to simultaneously solve the joint problem of community detection and group synchronization in a direct non-convex manner, in contrast to the existing method of semidefinite programming (SDP). Under a natural extension of stochastic block model (SBM), our theoretical analysis proves that the proposed algorithm is able to exactly recover the ground truth in $O(n\log^2 n)$ time for problems of size $n$, sharply outperforming the $O(n^{3.5})$ runtime of SDP. Moreover, we give a lower bound of model parameters as a sufficient condition for the exact recovery of GPM. The new bound breaches the information-theoretic limit for pure community detection under SBM, thus demonstrating the superiority of our simultaneous optimization algorithm over any two-stage method that performs the two tasks in succession. We also conduct numerical experiments on GPM and SDP to corroborate our theoretical analysis.} }
Endnote
%0 Conference Paper %T Non-Convex Joint Community Detection and Group Synchronization via Generalized Power Method %A Sijin Chen %A Xiwei Cheng %A Anthony Man-Cho So %B Proceedings of The 27th International Conference on Artificial Intelligence and Statistics %C Proceedings of Machine Learning Research %D 2024 %E Sanjoy Dasgupta %E Stephan Mandt %E Yingzhen Li %F pmlr-v238-chen24e %I PMLR %P 2899--2907 %U https://proceedings.mlr.press/v238/chen24e.html %V 238 %X This paper proposes a Generalized Power Method (GPM) to simultaneously solve the joint problem of community detection and group synchronization in a direct non-convex manner, in contrast to the existing method of semidefinite programming (SDP). Under a natural extension of stochastic block model (SBM), our theoretical analysis proves that the proposed algorithm is able to exactly recover the ground truth in $O(n\log^2 n)$ time for problems of size $n$, sharply outperforming the $O(n^{3.5})$ runtime of SDP. Moreover, we give a lower bound of model parameters as a sufficient condition for the exact recovery of GPM. The new bound breaches the information-theoretic limit for pure community detection under SBM, thus demonstrating the superiority of our simultaneous optimization algorithm over any two-stage method that performs the two tasks in succession. We also conduct numerical experiments on GPM and SDP to corroborate our theoretical analysis.
APA
Chen, S., Cheng, X. & Man-Cho So, A.. (2024). Non-Convex Joint Community Detection and Group Synchronization via Generalized Power Method. Proceedings of The 27th International Conference on Artificial Intelligence and Statistics, in Proceedings of Machine Learning Research 238:2899-2907 Available from https://proceedings.mlr.press/v238/chen24e.html.

Related Material