Coverage and Vacuity in Network Formation Games

The frameworks of coverage and vacuity in formal verification analyze the effect of mutations applied to systems or their specifications. We adopt these notions to network formation games, analyzing the effect of a change in the cost of a resource. We consider two measures to be affected: the cost of the Social Optimum and extremums of costs of Nash Equilibria. Our results offer a formal framework to the effect of mutations in network formation games and include a complexity analysis of related decision problems. They also tighten the relation between algorithmic game theory and formal verification, suggesting refined definitions of coverage and vacuity for the latter

Strategic Proxy Voting on the Line

This paper offers a framework for the study of strategic behavior in proxy voting, where non-active voters delegate their votes to active voters. We further study how proxy voting affects the strategic behavior of non-active voters and proxies (active voters) under complete and partial information. We focus on the median voting rule for single-peaked preferences. Our results show strategyproofness with respect to non-active voters. Furthermore, while strategyproofness does not extend to proxies, we show that the outcome is bounded and, under mild restrictions, strategic behavior leads to socially optimal outcomes. We further show that our results extend to partial information settings, and in particular for regret-averse agents.Comment: A preliminary version of this paper was presented in EUMAS202