UK General Election 2015

Back in March I was foolish enough to post about forecasting the outcome of the UK election on 7 May:

My hunch is that the LibDems will do better in their established areas than the national polling would suggest, and also that Labour will do better in Scotland than some of the forecasts are indicating.

Oh dear, my hunch was way wrong – so were other people’s forecasts, all based on opinion polling which turned out in retrospect, almost without exception (Survation and internal Labour party polling, both revealed after the event), to have been near useless until the exit poll. This chart updates one in the earlier post to show the final forecasts and the actual outcome:

That post had another chart, also updated below, which showed the relationship between the votes cast for Conservatives and Labour and the seats the parties obtained, both expressed as percentages. The first-past-the-post voting system tends to reward parties in that as they get more votes, they get even more seats (otherwise the dotted grey line would apply). However Labour does better than the Conservatives (the thin red line through their recent election results as opposed to the thin blue one). The dotted lines seem as good a guide as most of the more sophisticated forecasting models – assuming the forecast percentages of votes are correct.

Finally, will it be 1992 all over again in terms of the number of MPs? In the UK as a whole and looking at the two main parties, far worse for Labour alone, but in terms of Conservatives vs a Labour/Lib Dem/SNP bloc, remarkably similar. In England and Wales terms, Northern Ireland and Scotland both now being insignificant for the three main parties, Labour are slightly better placed than in 1992, but again in terms of Conservatives vs a Labour/Lib Dem bloc very similar: