Thursday, April 28, 2016

Amplifying white van man

Reuters --

Opponents of Britain's European Union membership have edged into the lead over the past two weeks, according to a YouGov poll for The Times, indicating President Barack Obama may have failed to swing support behind "In" vote in a June 23 referendum.

Set aside the fact that poll findings are being cited as Gospel so soon after their failure in the general election. The table above is from YouGov's detailed tabulations from the poll referenced above. It shows the composition of the survey by the UK social grade system (A=highest); the first column numbers is the actual number of respondents in each grade, and the second is the reweighted numbers to make the sample more representative -- it is claimed -- of the voting population.

The thing to notice is a massive upward reweighting, by 37 percent, of the C2 (skilled manual labour) group. It's a major assumption that your polling inference is stable when there's such adjustments going on with the sample.

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