The Inbetweeners
When it first was shown, I really liked “The Inbetweeners”
Anyway, as is increasingly often the case, this post has very little to do with its title and (surprise!) it’s again about the model for the UK general election.
There has been lots of talk (including in Andrew Gelman’s blog) in the past few days about Yougov’s new model, which is based on Gelman’s MRP (Multilevel Regression and Post-stratification). I think the model is quite cool and it obviously is very rigorous
Much of the hype (particularly in the British mainstream media), however, has been related to the fact that Yougov’s model produces a result that is very different from most of the other poll analyses, ie a much worse performance for the Tories, who are estimated to gain only 304 seats (with a 95% credible interval of 265-342). That’s even less than the last general election. Labour are estimated to get 266 (230-300) seats and so there have been hints of a hung parliament, come Friday.
Electoralcalculus (EC) has a short article in their home page to explain the differences in their assessment, which (more in line with my model) still gives the Tories a majority of 361 (to Labour’s 216).
As for my model, the very latest estimate is the following:
mean | sd | 2.5% | median | 97.5% | |
---|---|---|---|---|---|
Conservative | 347.870 | 3.2338147 | 341 | 347 | 355.000 |
Labour | 222.620 | 3.1742205 | 216 | 223 | 230.000 |
UKIP | 0.000 | 0.0000000 | 0 | 0 | 0.000 |
Lib Dem | 11.709 | 2.3103369 | 7 | 12 | 16.000 |
SNP | 48.699 | 2.0781525 | 44 | 49 | 51.000 |
Green | 0.000 | 0.0000000 | 0 | 0 | 0.000 |
PCY | 1.102 | 0.9892293 | 0 | 1 | 2.025 |
Other | 0.000 | 0.0000000 | 0 | 0 | 0.000 |
so somewhere in between Yougov and EC (very partisan comment: man how I wish Yougov got it right!).
One of the points that EC explicitly models (although I’m not sure exactly how
I think Yougov model is very extensive and possibly does get it right