Review of paradoxes afflicting procedures for electing a single candidate

Abstract

Three factors motivated me to write this chapter: The recent passage (25 February 2010) by the British House of Commons of the Constitutional Reform and Governance Bill, clause #29 of which states that a referendum will be held by 31 October 2011 on changing the current single member plurality (aka first-past-the-post, briefly FPTP) electoral procedure for electing the British House of Commons to the (highly paradoxical) alternative vote (AV) procedure (aka Instant Runoff ).1 Similar calls for adopting the alternative vote procedure are voiced also in the US. My assessment that both the UK and the US will continue to elect their legislatures from single-member constituencies, but that there exist, from the point of view of social-choice theory, considerably more desirable voting procedures for electing a single candidate than the FPTP and AV procedures. A recent report by Hix et al. (2010) – commissioned by the British Academy and entitled Choosing an Electoral System – that makes no mention of standard social-choice criteria for assessing electoral procedures designed to elect one out of two or more candidates.