Contextual Determinants of Electoral System Choice - Ã bo Akademi

concerning the ballot structure in contrast to the plurality ones. Each pluralityformula is characterized by a specific ballot structure, which, at the same time,constitutes a feature that distinguishes different plurality formulas from each other.2.2.3.2 Single Transferable VoteOf all electoral formulas used for legislative elections, the single transferable voteis often regarded as the most complex one. This formula was independentlyinvented in the mid-nineteenth century by Thomas Hare in the United Kingdomand Carl Andrae in Denmark (Reynolds and Reilly 1997: 83). Like AV, STVapplies preferential voting, and the electors can vote for as many, or as fewcandidates on the ballot paper as they wish. Electors are, however, advised todeclare as many preferences as possible, so as to maximize their influence on thefinal election result. Since STV is a proportional formula, it operates, in contrast toAV, with multi-member districts.Candidates are elected if they receive a specific quota (Droop) of the total vote in aconstituency. This quota is calculated by dividing the total number of valid votesby the number of seats to be allocated plus one, and rounding upwards or addingone. The first stage of the counting process involves the sorting of all ballot papersaccording to the first preferences of the voters. Any candidate who has attained anumber of votes equal to or greater than the quota is immediately elected. At thenext stage, all surplus votes of those candidates already elected, i.e. the number ofvotes by which the quota is exceeded, are transferred to the remaining candidatesaccording to the second-preference on the ballot paper. If no candidate has attainedthe quota, the candidate with the lowest number of first preferences is eliminated,and his or her second preferences are redistributed to the other candidates. At eachstage, every candidate that attains the quota is declared elected. The transfer of thesurplus votes of winning candidates and the votes of eliminated candidates, basedon second, third, fourth preferences and so on, continues until all seats in theconstituency are filled.According to Peter Mair, STV has three considerable merits: candidateaccountability, proportional outcomes and stable governments (1986: 292-299).Due to the preferential voting in rather small multi-member districts, STV has theadvantage of individual accountability usually associated with SMP, while31