How much can we rely on YouGov?
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Why does Kellner’s firm have the lowest Labour figures?
With today’s YouGov poll likely to take the edge off Labour on the spreadbetting markets we ought to look at how the internet pollster operates.
For since starting political surveys at the last General Election YouGov, headed by the well-known politcal writer Peter Kellner (above), has consistently produced figures that set it apart from the rest of the pollsters who rely on traditional interviews . Today’s 34% for Labour is 4-6% below the latest ratings from ICM, NOP, Populus and Communicate Research. It was YouGov, punters might recall, that first picked up the surge for UKIP at the Euro Election last June although, in the end, the pollster had an exaggerated figure.
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The main criticisms of YouGov are that those polled are restricted to members of the public who have registered and who have internet access. This, it is argued, could produce a skewed sample and that the people who volunteer to go on the list might be atypical.
The biggest oddity, as the polling commentator Anthony Wells has observed, is that YouGov operates in a way that should produce much higher Labour totals. He has noted:-
YouGov does not take into account the likelihood that someone surveyed will vote – this usually helps Labour.
YouGov weights the past voting recall of its samples at LAB 56%: CON 28%: LD 13.4%. This is very different from standard pollsters such as ICM which operates on LAB 46.5: CON 30.1 LD 17.6. So nearly a quarter more previously declared Labour supporters go into each sample than with other firms.
YouGov’s age profile seems to have the over 65s at less than 9% compared with more than 20% for the adult population as a whole. Given that this group is the one most likely to vote and to support the Tories this surely has an impact.
So why, in spite of all of this, does YouGov tend to be the least favourable pollster for Labour? We can only conclude that some people complete an internet survey in a totally different way than when answering questions over the phone to an interviewer. Could it be that being pro-Labour is something you are more likely to be in public than in private?
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Another feature of YouGov, some say, is that its methodology tends to magnify opinion shifts like UKIP last May. Could the latest LD surge be another example?
The pollster usually responds to criticism by pointing to its record which when tested against real votes is the best of any firm currently carrying out UK surveys. The majority of entrants to the site’s New Year competition predicted that the firm would by the top pollster at the General Election.
Latest IG Index spread prices: LAB 359-366: CON 183-190: LDs 70-74.
Latest Spreadfair prices: LAB 359-361.5: CON 188-190: LDs 68-71.9.
Mike Smithson