Last weekend the Sunday Telegraph published an ICM poll conducted in Glasgow East showing Labour ahead by 14 points. It’s a good lead, but a lot of people seem unconvinced by the poll. Let’s look at the reasons.

Firstly, the weighting of the poll. Some people have flagged up that on the unweighted figures Labour are only 4 points ahead of the SNP. This is irrelevant – the unweighted figures are skewed, even before we get to the politics they contained far too many people in social classes AB, and far too few people in social class D.

A few people have raised the question of the political weighting. ICM base their target weights on the last general election result, from back in 2005. Some people have worried whether respondents might have actually answered with how they voted in the Scottish elections in 2007, when the SNP did better. If that were the case, ICM should have weighted past SNP voters to a higher point. Confusion between the two past elections is a possible cause of a higher level of false recall than is usual, but ICM do specify in their question that they want to know how people voted at “the last General Election in May 2005”, they don’t just say last election, and they do assume some level of false recall anyway. There’s no way to rule out this factor, but neither is there any evidence to suggest it is affecting the result.

What the weighting does flag up is how unrepresentative the raw sample was. The proportion of people who owned their homes outright was twice what it should have been, the proportion of ABs in the sample was well over twice the proportion there really is in Glasgow East. At the most extreme extent, only 1% of the original sample voted Lib Dem in 2005 and they needed to be weighted up by a factor of 6 to get to the correct proportion.

None of this is a great surprise – the levels of severe social deprivation is some parts of Glasgow East are going to make them very difficult indeed to accurately poll. The more a sample relies upon weighting to make it representative though, the less robust the results are, and they weren’t actually very robust to start with: the sample size of the poll was 516, but once non-voters and some of the don’t knows were taken out, the final figures were based on 373 respondents, so we have a margin of error of 5% or so anyway.

There is also the issue of ICM’s reallocation of don’t knows, which boosted Labour’s lead from 11 points to 14 points. Normally this is a sound adjustment based on how people have behaved at past general elections. We cannot, however, have the same confidence that they behave that way in by-elections, and at Crewe and Nantwich it made ICM’s figures less accurate, not more so.

So, should we trust ICM’s figures? Well, there isn’t anything wrong with what ICM have done, it is just a very difficult contest to poll, as evidenced by the small sample size and the extreme weighting ICM were forced to resort to. While the large margin of error and sample problems should make us slightly wary, a 14 point lead is very substantial. The biggest caveat is probably the least technical – a poll is only a snapshot, and it was conducted with two weeks of the campaign still to go. Even if Labour were 14 points ahead a week ago, it doesn’t follow that they’ll still be there next week.


12 Responses to “Are Labour really ahead in Glasgow East?”

  1. Well, there aren’t many residents in this constituency, a great many of those move around a lot, a huge proportion of them aren’t registered to vote, a lot of them are Irish, many of them aren’t sure how they voted last time, or even when last time was, the opinion poll looks to hsve interviewed proportions untypical as to social class, not many even of the registered voters in this constituency usually vote and even fewer will probably vote next week, reallocation of don’t knows is probably invalid in this Constituency, and Scottish Nationalism is an issue.

    All factors, I would say, which make it completely impossible even to guess at the result.

    So, it’s going to be a SURPRISE. Don’t let’s waste any more time on it.

  2. Anthony,

    A good post as ever. I was one of those who found the result odd in that it didn’t tie in with what i saw on the ground. However i fully accept that ICM have tried to do the best they can for their clients with the data they had.

    If someone is to blame I think it is back to the media who rarely add the necessary caveats when a poll is done.

  3. I am affraid it will be closer than the ICM said. The tory press have been very clever to spin poverty in glasgow as the fault of labour, when it is the tories fault. The fact labour has brought in the commonwealth games, 3000 jobs via the aircraft carriers and the mini wage and tax credits seems to have been ignored. There is a real policy by the tories to paint the labour party as causing poverty it was Thacther who wrecked the city, not new labour.
    The English tories do not care that this result may end the union. Scottish tories are just pawns for them.

  4. “but ICM do specify in their question that they want to know how people voted at “the last General Election in May 2005?”

    That phrasing is still ambiguous within Scotland. Elections to the Scottish parliament are seen as general elections, with what ICM call a general election being viewed as (and called) a “Westminster Election”.

    If I were asked how I voted in the last general election, I would ask for clarification as to which one it was, but I do wonder how many people would, and how many would just assume the polling organisation meant the Holyrood election.

  5. I’ve been out the last two weekends working in Glasgow East. There is a swing on to the SNP and the Tory/Lib Dem vote will get squeezed. The Labour vote looks like a large proportion will sit in the house rather than vote.

    Based on Scottish Parliament 36% turnout then on that basis if 3,000 Labour voters vote SNP and a proportion of the tories/Lib Dems vote SNP to give Brown a bloody nose the SNP will win.

  6. I remember campaigning in the first post Holyrood Westminster General Election and on a number of occations when I either told people it was for the UK Parliament or how would they vote in an Independence referendum the reply was;

    ” But we are independent we just voted Yes to it”…..

    Peter.

  7. Anthony:

    Isn’t it just too big a hill to climb? What is the record swing in “normal” circumstances (GE to GE) or between GE and a Bye election in a “safe” seat? I wouldn’t count the likes of Leyton 1965, or Tatton 1997 as “normal”.

  8. The problem with your reasoning Anthony is that the swing already happened. The difference between the 2005 general and the 2007 Holyrood election saw the SNP achieving a seismic shift in voting preference in Scotland. That process has continued since the SNP took government.

    In England there is a relationship between a seat and how people voted in the last election, in Scotland there is very little. Things have changed here dramatically!

    That said Labour could still hold on here because there are some seats which are half stuck in a time warp…

  9. Common sense would suggest that the broad thrust of the poll would be accurate. Large levels of benfeit dependency is constituencies like Glasgow East mean that the population will naturally be disposed towards Labour. With housing paid for and local taxes paid for as well as other benefits available they will support statist parties like Labour without fear of the consequential tax increaes that they won’t have to pay. The only thing that could possibly throw the contest into doubt would be the extent to which Labour or the SNP are able to mobiize their supporters. Labour will only lose if their supporters lack the commitment to vote.

  10. I’m convinced that the reported 2005 votes are partly “how I wish I’d voted” rather than clear recollection. Not only did the sample under-report as 2005 Liberals (which is weird with a AB bias), but they over-reported as 2005 SNP voters.

    The subsequent PSO poll predicts final shares pretty close to the ComRes unweighted sample, incidentally.

  11. Now that the james purnell plan of making every one on benefit clean the graffiti & pick up little has been made public, everyone will do the decent thing & switch to SNP.
    And Of course Glasgow is going to be one of the trial areas.
    The next thing this government will do is making all on benfits wear the yellow star.