Tuesday, 9 May 2017

I shall try and show you how reliable opinion polls are - my Coalville Times column

It’s fair to say that my political journey from leader of the labour group on the district council to conservative party activist has been a well-documented one, not least in the pages of this newspaper.

Although I maintain that my own personal politics haven’t changed that significantly, there is after all not much of a step from centre left to centre right on the political spectrum, there is little doubt if opinion polls are to be believed a great many others will be making the same electoral journey as me both in this week’s county council elections and on June 8th when we select our next Prime Minister.

Whenever I speak with people about opinion polls, I know I need to get out more, one thing I hear again and again is that ‘you can’t believe them, they are always wrong.’

So this week I should like to put to rest the notion that these surveys, carried out by professional pollsters and reported on so widely in the media, are usually inaccurate. In fact, quite to the contrary, I shall try and show you how reliable they really are.

First things first. Opinion polls are not the same as the start of every question on Family Fortunes. Pollsters do not simply ‘survey a hundred people’ at random.

Opinion polls aren’t the same as a phone vote on ‘This Morning’; for a start there is nothing to stop you phoning and voting on those things more than once and, let's face it, it is quite possible that This Morning viewers are not necessarily  representative of the wider population. There probably isn’t too many office and factory workers amongst their daily viewers, is there?

No, opinion polls, are weighted by pollsters to reflect the wider population. Companies like Ipsos MORI and ComRes will seek to ensure that they include the right number of men and women, rich and poor, black and white to reflect the wider population. The theory being that the responses of ten or twenty middle aged men with similar incomes and backgrounds working in factories will tend to be representative thousands who share a similar background. It’s a remarkably accurate way of predicting outcomes.

Now pollsters know that their samples aren’t always perfect and so they recognise that there is usually ‘a margin of error’. Maybe, they haven’t been able to sample enough retired people to be representative?

It’s that margin of error that tells you within a few percentage points what results are likely to be.

So when I hear that the pollsters got it wrong on last year's referendum go back and look at what the polls actually said. Yes most suggested that we would vote Remain but nearly all of them had the actual result in their margin of error. With the referendum it wasn’t that the polls were wrong but we weren’t understanding what they were trying to say to us.

There has been in living memory two times when opinion polls in the UK did get things wrong, the 1992 and 2015 General Elections. In both of them wins were predicted for Labour when in fact in both of them the Conservatives won comfortably.

After both elections pollster tried to figure out what went wrong and they came up with similar answers both times. Some people wanted to say they were voting for the ‘compassionate’ option of Labour but once they got in to the privacy of the polling booth they took the ‘competent’ option of voting Conservative. There’s even a name for these people, they’re called ‘shy Tories’.

Now all of this matters because it tells us something about the upcoming general election.

In all polls so far the Conservatives have a commanding lead well outside the margin of error and there is absolutely no precedent for their vote being overstated, in fact because of that shy Tory issue it could well be significantly more than what the polls suggest.

In truth opinion polls are pretty accurate, real polls far more so. Over the next day or so we will know the results of the County Council elections. If the Tories pick up seats here in North West Leicestershire and South Derbyshire, if they win the West Midlands mayoral contest and maybe even take control of Nottinghamshire be prepared for a very big landslide come June 8th.

Simply put Labour supporter can’t really place in faith whatsoever in the current opinion polls being wrong and the true result being in their favour. The only way they win next month is to start turning them around.              

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