Friday, 8 May 2015

FPTP vs PR

I'm sure I've gone into this before, so I won't belabor the point but this election is a great demonstration of the flaws with First Past the Post, when combined with single member constituencies.

The latest data I have shows 643 seats declared Table updated to show final result (and I'll try to update these numbers as more data comes in). It shows that 30.7m votes have been cast, which would equate to 47,223 votes per seat in a perfect democracy.

Looking at any party that got at least 47,223 votes, we see:


PartySeatsvotesvotes per seatseats under PR
Alliance Party061,556-1
UKIP13,881,1293,881,12983
Green Party11,157,6131,157,61325
Liberal Democrat82,415,888301,98652
Plaid Cymru3181,69460,5654
Ulster Unionist Party2114,93557,4682
Sinn Fein4176,23244,0584
Labour2329,344,32840,277199
Conservative33111,334,92034,244242
Social Democratic & Labour Party399,80933,2702
Scottish National Party561,454,43625,97231
Democratic Unionist Party8184,26023,0334

(updated to reflect final score - the single "other" seat is left off of this list)

Doesn't look so good for UKIP, at 3.8m+ votes per seat, does it. That should come down a bit when Thanet South is declared. Greens are also in a bad place with over 1m votes per seat. Interesting to see the Lib Dem position - under PR they'd have got a lot more seats.

The system does seem to be set up to ensure that the bigger parties cannot be challenged.

For the record, the PR figures above assume that anyone getting less than enough votes for one seat would be ignored, and the seats split among the remaining parties according to vote share.

Interestingly, these PR figures would still leave Conservatives and UKIP 1 seat short of a majority if they worked together.

Someone at Tim's place mentioned that UKIP have more votes than Lib Dems and SNP put together - something to think about!

Numbers taken from the BBC page at http://www.bbc.co.uk/news/election/2015/results