Optimizing Viscous Democracy

TL;DR

This paper introduces viscous democracy, a variant of liquid democracy that incorporates a viscosity factor to limit delegation influence, leading to improved decision quality and reduced super-voter dominance.

Contribution

It formalizes viscous democracy, demonstrates its benefits over liquid democracy, and explores its practical effects through simulations across various social network models.

Findings

High viscosity reduces super-voter influence.

Viscous democracy improves group decision accuracy.

Optimal delegation in viscous settings is NP-hard.

Abstract

Viscous democracy is a generalization of liquid democracy, a social choice framework in which voters may transitively delegate their votes. In viscous democracy, a "viscosity" factor decreases the weight of a delegation the further it travels, reducing the chance of excessive weight flowing between ideologically misaligned voters. We demonstrate that viscous democracy often significantly improves the quality of group decision-making over liquid democracy. We first show that finding optimal delegations within a viscous setting is NP-hard. However, simulations allow us to explore the practical effects of viscosity. Across social network structures, competence distributions, and delegation mechanisms we find high viscosity reduces the chance of "super-voters" attaining large amounts of weight and increases the number of voters that are able to affect the outcome of elections. This, in turn, improves group accuracy as a whole. As a result, we argue that viscosity should be considered a core component of liquid democracy.