Vote splitting

Abstract: Measures of electoral system disproportionality and of party system volatility (as well as malapportionment and vote splitting) present similar statistical issues in terms of deciding what index is most appropriate, but it is not common to view indices of disproportionality and volatility as serving similar ends. Making use of 12 different criteria, we evaluate 19 indices that have been previously proposed as measures of either disproportionality of electoral seats–votes results or over-time volatility of party vote (or seat) shares. We suggest that, on balance, Gallagher’s (1991) index, which has achieved increasing acceptance in the seats–votes literature on disproportionality (see esp. Lijphart, 1994) offers the most desirable combination of features, although the advantages it offers over the Loosemore-Hanby index are not large and are debatable. We also find that Dalton’s principle of transfers presents an ambiguity when one party has a larger number of excess seats, while another has a larger propor...

Abstract: Mixed compensatory systems have risen in popularity in recent years. Under such systems, single-seat districts elect only the leader of the local suffrage, but the systems nevertheless produce (nearly) proportional outcomes overall, via compensatory mandates. Elections in Albania, Italy, Lesotho, and Venezuela, however, demonstrate a particular loophole for such systems: strategic voting, organized by political parties. Large parties can achieve over-representation by encouraging their voters to split their votes. In this way, they outsmart the compensatory mechanism designed to lead to proportional results. These disproportional results are particularly controversial, since they are deliberate and strategic. This article takes the 2005 Albanian elections as its main case study, and uses simulations to illustrate its political consequences.

Abstract: U.S. senators frequently vote against the preference of their constituency, assuming that such a preference exists. Both of a state's senators represent the same constituency. Whenever they split their votes, one or the other is necessarily going against the constituency preference. For the sample of defense-related votes analyzed above, “misrepresentation” — either observable vote splitting or unobservable vote matches that go against the constituency preference — occurred at least 37 percent of the time, at least 46 percent on one vote. Although party differences accounted for more than two-thirds of the vote splitting, a substantial number of splits remained. Besides, a party difference for a state's senatorial pair is itself problematical.

Abstract: The first ever simultaneous general and local elections in Denmark (November 2001) allow for a comparison of Danish voters’ inclination towards inter-level ticket splitting with similar phenomena in Sweden and England. Inter-level split-ticket voting occurs when voters cast their vote on two different parties in the two different (but simultaneous) elections; this happened far more often in Denmark in 2001 than in the two other countries. One hypothesis suggests that this owes to party system differences between the three countries, since both the number of parties running in the different elections and the discrepancy between the national and the local party systems are expected to influence the level of inter-level vote splitting. However, elec-tion statistics and survey data based analyses (Denmark in 2001, Sweden in 2002, and England in 2001) give only limited support to the hypothesis. It appears that Danish voters did in fact split their 2001 national and local votes more than Swedish and English voters did and more than party system differences can account for.