How to Appease a Voter Majority
Prasanna Ramakrishnan (Stanford)
Monday, April 7th 2025, 2-3pm
Abstract:
In 1785, Condorcet established a frustrating property of elections and majority rule: it is possible that, no matter which candidate you pick as the winner, a majority of voters will prefer someone else. You might have the brilliant idea of picking a small set of winners instead of just one, but how do you avoid the nightmare scenario where a majority of the voters prefer some other candidate over all the ones you picked? How many candidates suffice to appease a majority of the voters? In this talk, we will explore this question. Along the way, we will roll some dice — both because the analysis involves randomness and because of a connection to the curious phenomenon of intransitive dice, that has delighted recreational and professional mathematicians alike ever since Martin Gardner popularized it in 1970.
Based on joint work with Moses Charikar, Alexandra Lassota, Adrian Vetta, and Kangning Wang