Pivotal voting and the emperor's new clothes

Abstract.

A leading recent line of work in game theory applied to politics exploits the “pivotal voting” insight introduced by Austen-Smith and Banks [1]. The most prominent follow-on papers have been by Feddersen and Pesendorfer [2, 3, 4, 5], where a particularly striking result is that in a large election, the winner with many poorly-informed voters will be identical to the winner under full information. But of course any result whatever can be proven if sufficiently implausible assumptions are allowed. This review provides simple derivations of the elections result for both the FP 1996 model [2] and then for the (generalized) FP 1999 model [4]. The resulting transparency makes it easy to see the relation between the models, but also why neither result is relevant to actual elections.