Saturday May 8, 2010
The NYTimes, reporting on calls for electoral reform in the UK:
The Liberal Democrats, supported by the Electoral Reform Society, favor a type of proportional representation based on the so-called single transferable vote. Under that system, voters rank the candidates in order of preference. Votes for the lowest-ranking candidates are redistributed to the voter’s second choice. The system is devised so that if a party wins, say, 25 percent of the vote, it should win 25 percent of the seats.
As any observer of Australian politics would tell you, that is not how Federal House of Representatives elections work. For example, the Greens won 7.8% of the House vote in 2007, but no seats. The Nats won 5.5% of the vote, but 10 of 150 seats (6.7%).
In 1990, the Australian Democrats won 11.3% of the vote, but zero seats.
The geographical distribution of party support still matters if you have a district-based system. STV doesn’t get you PR, at least not “automatically”, and its a misnomer to call STV a form of PR.