LondonJohn
Penultimate Amazing
- Joined
- May 12, 2010
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Came across this BBC article about the polls:
http://www.bbc.com/news/election-2015-32572745
According to their numbers UKIP is 3rd after Cons and Labour and ahead of the Lib Dems. Greens are 5th and SNP doesn't even rate a mention, being lumped in with the "others".
Are these poll numbers accurate?
This seems to be different from what I read elsewhere.
As has already been alluded to in another response to this post, the raw percentages of population are relatively meaningless if one is seeking to predict the actual constituency-win distribution of the election (which is the only measure which counts).
To take this concept to its logical extreme, imagine if voters in every single constituency in the UK voted according to the percentage splits in this poll. If that happened, the Conservatives would win every single seat.
Obviously, therefore, one needs to know how to apply these numbers (and, more importantly, any swings implied by the movement of these numbers over time) on a constituency-by-constituency basis, and one also has to take into account local/regional factors. It's an incredibly complex an difficult piece of psephological analysis, which is also notoriously inaccurate.
Polling companies are very good indeed at working out national population splits of voting intentions, and these numbers are usually extremely accurate. Where they run into huge trouble (and it's the kind of trouble that renders their "expertise" somewhat worthless....) is on two major fronts:
1) Working out how people's actual voting patterns (including likelihood of turnout, and saying one thing to pollsters but voting another way on the day) differ from the answers they give to election pollsters;
2) Translating population split numbers onto a constituency-by-constituency analysis, in order to try to predict the only numbers that really matter: the number of seats each party is likely to win in the election.
Nobody can yet get this right on a national basis. The parties themselves know this as well. They also know that the entire election comes down to a small proportion of marginal seats (e.g. Kensington will never ever be anything other than a Tory seat, and Liverpool Walton will never ever be anything other than a Labour seat). They conduct their own private polling in the key marginals, and its this polling - and definitely not the national polls quoted in the media - which best inform the parties themselves of the most likely result.