A note of caution on the prospects for a progressive alliance: We are bad at predicting our own behaviour

Best for Britain is proud of its opinion poll, which forecasts how people would vote given various scenarios where parties co-operate with one another at the next general election.

Most Liberal Democrat and Green voters would vote Labour if their parties stood down, their findings say. Equally, Labour voters would mostly be happy to vote Lib Dem or Green.

It looks easy, doesn't it?

As Freddie and Fiona once put it to Lord Bonkers:

"All we need do ... is change the Labour Party constitution, have all the parties agree a common manifesto and then get them to stand down wherever we think they should."

But then F&F aren't old enough to remember the Alliance and what it is like when the Conservatives and the press are looking for divisions to exploit. It would be far worse now with more parties involved and what Lord Bonkers would call "the electric social media".

There is another problem with this poll. Most opinion polls ask people how they would vote if there were an election today. This one asked them how they would vote in a year or two's time given a number of different conditions,

The problem is that we are poor at predicting our own behaviour. As a post on the Research Digest blog once expressed it:

Psychologists have identified an important reason why our insight into our own psyches is so poor. Emily Balcetis and David Dunning found that when predicting our own behaviour, we fail to take the influence of the situation into account. 

By contrast, when predicting the behaviour of others, we correctly factor in the influence of the circumstances. This means that we’re instinctually good social psychologists but at the same time we’re poor self-psychologists.

So this sort of polling is unlikely to provide the proof that Best for Britain thinks it has. They might, however, do better if they ask people how they think their neighbours would react faced with these conditions.

For instance, I would not see a progressive alliance as a way of denying people choice and so resent it, but I suspect many possible anti-Tory voters would.