Saturday, 9 May 2015

the advantages of geography

The UK General Election results show the usual pattern of a disconnect between seats gained versus votes cast.

Proportion of seats gained (left) versus proportion of votes cast (right).
Data from BBC website.
The bigger parties get proportionally more seats, as the smaller parties tend to have their support spread too thinly to get a seat anywhere.  This year, with the landslide victory of the Scottish National Party, taking 56 of the 59 seats in Scotland, we dramatically see the effect of spread versus concentration of support.

The LibDems got 8 seats with 2.42M votes; the SNP got 56 seats with 1.45M votes; the Greens got one seat with 1.16M votes.  If seats were proportional to total votes, they would instead have got 51, 31, and 25 seats respectively.  Clearly the SNP are benefitting from the concentration of their vote.  (Yet since they only put up candidates in Scotland, who knows how many more votes they would have got if people elsewhere in the UK could have voted for them too?)  UKIP also got one seat, despite having a frightening 3.88M votes, which would proportionally have given them a whopping 82 seats.

Four years ago we had a referendum on whether to keep the First Past The Post (FPTP) voting system that results in these anomalies, or change to the Alternative Vote (AV) system.  We kept FPTP.  It’s not clear what would have happened here under AV, as people may have voted tactically this time around, not voting for who they really wanted, in order to keep out those who they really hated.  AV means you don’t have to vote tactically; you can vote for your favourite minority party without “wasting” your vote.

Whatever, the graphic shows how disenfranchised “minority” voters are.

1 comment:

  1. We needs a better voting system in the US as well. The Republicans get more seats than they deserve for a number of reasons. First, they manipulate the congressional districts to concentrate the Democrats in fewer districts. Second, Democrats would tend to be concentrated in cities even without Republican help. Third, each state, no matter its population, gets 2 Senate seats.