— Mike Smithson (@MSmithsonPB) August 14, 2015
The President of YouGov, Peter Kellner, explained in a separate article that they had looked at the polling figures again in the light of the data from the party showing the huge influx of names in the final few days. He goes on:-
“..I have taken the support YouGov found in each of these groups and adjusted the size of each to the numbers provided by Labour on Wednesday. The effect is to lift Jeremy Corbynâ€™s support to 57 per cent, four points higher than we published on Tuesday. This is because we found that he was especially popular among people who have joined the selectorate, especially trade unionists. As a result he may have gained disproportionately from the 220,000 people who signed up for the election in the past few days.
I should stress that this is a purely arithmetical exercise. We donâ€™t know whether the late sign-ups are especially pro-Corbyn â€” or have joined in large numbers with the aim of preventing the leftwinger from leading the party. Nor can we be sure how the turnout will vary: implicit in my sums is that the turnout of each group will be the same. If it isnâ€™t, the overall result will be different.”