Speaker: 
Zoe Christoff

Title:
From DeGroot processes to liquid democracy

Abstract:
We study a special case of opinion diffusion in networks where each agent holds binary opinions and follows a unique influencer. These simple “follow your guru” processes, which we name “Boolean DeGroot processes”, lie at the intersection of two more general frameworks for opinion diffusion: the stochastic model proposed by DeGroot, and the more recent approach, stemming from the literature on judgment aggregation, of “Propositional Opinion Diffusion”. We establish conditions for convergence of opinions in Boolean DeGroot processes and in a simple generalization of them, we show how these conditions can be captured by modal logics, and we apply the convergence results to gain a novel insight into the collective decision-making system known as “liquid democracy”. This is joint work with Davide Grossi.