Speaker:     Arkadii Slinko
Affiliation: The University of Auckland
Title:       Geometric properties of voting rules
Date:        Monday, 18 Jun 2012
Time:        4:00 pm
Location:    Room 6115, Owen Glenn Building

Each axiom of voting rules considered in Economics and Political Science reflects some notion of fairness, e.g., unanimity requires that, if all voters vote for a certain candidate, this candidate should be elected; anonymity requires that it does not matter who submitted which ballot; monotonicity requires that, if support of the winner of the election grows, she should remain the winner of the election.

In a completely different vein we investigate the geometric properties of voting rules. We define a graph on the set of all elections as vertices and colour them  in a such a way that two vertices have the same colour if and only if the corresponding elections have the same winner. We determine for which classic social choice rules the monochromatic components are connected, convex, etc.

This is a work in progress in co-authorship with Edith Elkind, Svetlana Obraztsova, Piotr Faliszewski.