Stochastic gradient descent methods and uncertainty quantification in extended CLSNA models

Xiaojing Zhu Co-Author
Boston University
 
Cantay Caliskan Co-Author
University of Rochester
 
Dino Christenson Co-Author
Washington University in St. Louis
 
Konstantinos Spiliopoulos Co-Author
Boston University
 
Dylan Walker Co-Author
Chapman University
 
Eric Kolaczyk Co-Author
McGill University
 
Hancong Pan First Author
 
Hancong Pan Presenting Author
 
Monday, Aug 5: 9:50 AM - 10:05 AM
2654 
Contributed Papers 
Oregon Convention Center 
Coevolving Latent Space Networks with Attractors (CLSNA), introduced by Zhu et al. (2023; JRSS-A), model dynamic networks where nodes in a latent space represent social actors, and edges indicate their interactions. Attractors are added at the latent level to capture the notion of attractive and repulsive forces between nodes, borrowing ideas from dynamical systems theory. The reliance of previous work on MCMC and the requirement for nodes to be present throughout the study period make scaling difficult. We address these issues by (i) introducing an SGD-based parameter estimation method, (ii) developing a novel approach for uncertainty quantification using SGD, and (iii) extending the model to allow nodes to join and leave. Simulation results suggest that our approach results in little loss of accuracy compared to MCMC, but can scale to much larger networks. We revisit Zhu et al.'s analysis of longitudinal social networks for the US Congress from social media X and reinvestigate positive and negative forces among political elites. We now overcome an important selection bias in the previous study and reveal a negative force at play within the Republican Party.

Keywords

Longitudinal social networks

Attractors

Partisan polarization

Dynamic networks analysis

Co-evolving network model 

Main Sponsor

Social Statistics Section