Let’s Talk Pencil-Pusher: Lesson IV—Opinion Polling (Fourth of a series, translating bureaucrat-speak into what it means for folk in East Lothian)
The Sunday Herald is abuzz with another poll. “Labour is on course for a resounding victory in May’s Holyrood election as voters turn away from the Liberal Democrats and the SNP” it trumpeted. “Labour polled 41% on the constituency vote, up 8.8 percentage points on the 2007 election. The SNP got 32%, down 0.9 points, the Conservatives 15% (down 1.6), the LibDems 8% (down 8.2) and 4% plan to vote for other parties (up 1.9).”
Whoa…did they? Dig into the actual figures and you find voting intention figures in the original, unadjusted YouGov sample show an SNP lead of 13 points in the constituency vote – 41% for the SNP, compared to 28% for Labour, 18% for the Tories, and 6% the Lib Dems. On the list vote, the SNP are ahead by 8 points – 34% for the SNP, 26% for Labour, 19% for the Tories, and 6% for the Lib Dems. Huge difference; what happened?
Seems that YouGov always ‘normalises’ its results, based on a calibration that 16% of voters for Westminster must vote SNP, so their results are skewed to reflect that. Crazy? perhaps. Unbiased? The Green Party funded this one to coincide with their conference and it shows them forming a government with Labour…so maybe not.