  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.
