Jonathan Jones

What difference the Scottish independence question makes

What difference the Scottish independence question makes
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A very useful contribution from Lord Ashcroft this morning, in the form of a poll he’s commissioned on Scottish independence. What sets Ashcroft’s poll apart from previous surveys is that he asks three different questions to three different sets of around 1,000 Scots.


The first is the question Alex Salmond wants on the ballot paper at the referendum: ‘Do you agree that Scotland should be an independent country?’ 41 per cent say ‘Yes’ and 59 per cent say ‘No’. The second alters the wording only slightly, to ‘Do you agree or disagree...’ and finds 39 per cent agreeing (i.e. supporting independence) and 61 per cent disagreeing. So far, fairly consistent: the difference between these two sets of results is within the poll’s margin of error.


But ‘agree or disagree’ questions have a tendency to bias results towards the ‘agree’ side. Anthony Wells pointed this out in a great post a couple of days ago, with some examples. For example, a single poll last month had both 74 per cent agreeing that ‘The Government should not increase public borrowing any further and its top priority should be to pay off the nation’s deficit as soon as possible’ and 49 per cent agreeing ‘The Government should borrow more in the short term to increase economic growth as much as possible even if it means reducing the deficit more slowly’. In other words, at least 23 per cent of respondents said both that borrowing should be increased AND that borrowing should not be increased.


To counteract this phenomenon, Ashcroft’s third question asks people to choose between two different options: ‘Should Scotland become an independent country, or should it remain part of the United Kingdom?’ Under this formulation, he finds significantly greater support for the union: 33 per cent choose independence, against 67 for staying in the UK. As well as avoiding the bias towards agreement, Ashcroft suggests two other reasons for this question finding less support for independence than Salmond’s:

‘First, the use of “be”, rather than “become”. Asking whether Scotland “should become an independent country” emphasises, however faintly, that people would be voting for a significant change. This would probably dampen enthusiasm for independence... Second, and more striking still, the Salmond Formulation does not mention the United Kingdom – a point made powerfully by Alistair Darling, among others.’

SNP’s claim

Ipsos MORI poll