Polling agencies weight responses by likelihood of voting. Traditionally, the weighting is done by asking people: “How likely (out of 10) are you to vote?” This year, two agencies (ICM and ComRes) have stopped doing this. Instead, they weight responses by demographic variables such as age and class. For example, young people are less likely to vote than old people, so young people’s responses count for less. Working-class people are less likely to vote than middle-class people, so working-class responses count for less.

Now consider how these polls are used. If all you want to know is what would happen in an imaginary election happening today, then you’re entitled to use any variable with predictive power. But that is not how polls are used. Polls are treated as a barometer of public opinion. They set the news agenda. It becomes common knowledge that Labour is “unpopular” and “out of touch with public opinion” because they are polling badly, whereas the Conservatives are “popular” and “in touch with public opinion” because they are polling well.

For this purpose, it is concerning that the voices of the young and the working class are given less weight by polling agencies than the voices of the old and the middle class – and that, for ICM and ComRes, your opinion as a young or working-class person still merits less weight even if you tell them you intend to vote.

Dr Jonathan Birch

London School of Economics

• The fact that Jeremy Corbyn has lost the support of C2 and DE voters may at first appear surprising (Poll: May wins hearts of working class, 16 May). After all, the policies Labour are putting forward are popular and poll well. The cause of the disparity between policy and personality is, simply, the “Islington factor” and the loss of Labour’s working-class base.

Corbyn is a fairly typical middle-class socialist. When working-class people encounter him, their class instinct says “hypocrite”. They do not see someone who will fight against his own class interests. They may be wrong in this, but history tells them otherwise. May is a traditional Tory. What you see is what you get.

Labour’s problem is that Jeremy Corbyn may have made it once again a party for the working class, but it is no longer of the working class. Therein lies the cause of its dilemma.

Nick Moss

London

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