TL;DR: One reason often put forward for the lack of minor-party success in single-member district/plurality electoral systems is that voters hesitate to waste their support on political parties that have little chance of winning.
Abstract: One reason often put forward for the lack of minor-party success in single-member district/plurality electoral systems is that voters hesitate to waste their support on political parties that have little chance of winning. On this basis, a voter may cast his ballot for one of the major parties even though he prefers a certain minor party. A good illustration of this line of thought is provided by Anthony Downs in his work, An Economic Theory of Democracy.l Downs claims that in the American presidential election of 1948 some of the voters who preferred Henry Wallace and his Progressive party nevertheless voted for the Democratic candidate. They did so, says Downs, because they felt that Wallace had no chance at all, and that the more people who voted for him, the fewer who would vote Democratic. If the Democratic vote fell low enough, then the Republicans-the least desirable party from the Progressive viewpoint-would win. In sum, Downs argues that a vote for Wallace increased the probability that the party the Progressives favored least would win; and, to avoid this, some Wallace supporters voted for the candidate ranking second in their preference ordering.2 The best known proponent of this "wasted vote" thesis is Maurice Duverger. According to Duverger, "in cases where there are three parties operating under the simple-majority, single-ballot system, the electors soon realize that their votes are wasted if they continue to give them to the third party; whence their natural tendency to transfer their vote to the less evil of its two adversaries in order to prevent the success of the greater evil." 3
TL;DR: The authors used data from Canadian federal elections from 1988 to 2000 to test the expected utility model, developed by McKelvey and Ordeshook (1972), on those with an incentive to vote strategically across all four elections.
TL;DR: The efficiency gap is a useful indicative measure of partisan gerrymandering under the circumstances of cases like the one currently before the Court, in which each party earns about half the votes and a large efficiency gap persists under plausible variations in voter behavior as mentioned in this paper.
Abstract: Electoral districting presents a risk of partisan gerrymandering: the manipulation of electoral boundaries to favor one political party over another For three decades, the US Supreme Court has failed to settle on a legal test for partisan gerrymandering, and such claims have uniformly failed Until recently Plaintiffs prevailed before a three-judge federal panel in Wisconsin by leveraging a new measure called the “efficiency gap,” which quantifies partisan gerrymandering in terms of two parties’ relative efficiency at translating votes for their party into seats in government The case is now before the Court, which may embrace the efficiency gap approach and thereby remake the law of electoral districting Through a synthesis of mathematical and legal analysis, this Article examines the efficiency gap measure, focusing particularly on its underlying methodological choices and electoral assumptions as well as its relationship to competitiveness, seats-votes proportionality, and voter turnout
The efficiency gap is a useful indicative measure of partisan gerrymandering under the circumstances of cases like the one currently before the Court, in which each party earns about half the votes and a large efficiency gap persists under plausible variations in voter behavior Relying in part on the efficiency gap measure, the Court should rule in favor of the plaintiffs However, a mapmaker can achieve a below-threshold efficiency gap with a skewed bipartisan gerrymander that carves a state up into uncompetitive districts denying minority parties sufficient representation For example, a party that earns only 59% of the vote can secure a filibuster- and veto-proof 75% supermajority of the legislature with a below-threshold efficiency gap For this and other reasons, the Court should not adopt the efficiency gap as the exclusive definitional measure of partisan gerrymandering, such that a plan would be invalid if and only if it exhibited a large, durable, and unjustified efficiency gap Instead, the Court should permit some flexibility for scholars, litigants, and courts to refine measurement approaches over time and under varying circumstances One approach worth future exploration is a variation on the efficiency gap that defines a surplus vote in terms of the full margin of victory and compares wasted vote shares instead of totals Finally, the Court should be aware that any measure, like the efficiency gap, that compares votes to seats entails the perverse risk that partisan voter suppression may operate to reduce the apparent severity of partisan gerrymanders
TL;DR: The authors argue that while poll results certainly increase the likelihood of changing one's vote, explicit information signals can increase this probability even more and that these effects will be moderated by the presence of a counter message and the sponsor of the explicit information signal.
Abstract: While theoretical work on strategic voting emphasizes the importance of elite messages in persuading minor party supporters to abandon their first preference, few empirical studies have examined this relationship. I argue that while poll results certainly increase the likelihood of changing one’s vote, explicit information signals can increase this probability even more. Furthermore, these effects will be moderated by the presence of a counter message and the sponsor of the explicit information signal. These hypotheses are tested with data generated from two experiments.
TL;DR: In this article, Cohan, McKinlay and Mughan made several valuable points, including a demonstration that patterns of transfer votes may be more important than the distribution of first preference votes in determining the result of elections under the single transferable vote (STV) system, and an extension of the wasted vote concept to STV, majority, and proportional elections.
Abstract: When the results of an analysis fly in the face both of generally accepted theory and the practice of professional politicians, it is usually a good idea to reconsider whether the point is really established. Such is the case with the small literature regarding the effects of nomination strategies on the outcomes of Dail Eireann elections that has developed in these pages since the publication of an article by Cohan, McKinlay and Mughan (‘The Used Vote and Electoral Outcomes: The Irish General Election of 1973’, this Journal, v (1975), 363–83). The original article made several valuable points, including a demonstration that patterns of transfer votes may be more important than the distribution of first preference votes in determining the result of elections under the single transferable vote (STV) system, and an extension of the wasted vote concept to STV, majority, and proportional elections. Unfortunately, the notes that have followed have all focused on the most questionable conclusion of the original article, that overnomination hurts a party's chances of electing the maximum possible number of deputies.