Two polls, same timing, different outcomes. Eh?
How can we explain both MORI and ICM?
One thing you must not do, when you see a shock polling outcome such as the survey for by MORI for the Observer this morning, is immediately to conclude that it must be a rogue or an outlier.
The fact is that we don’t know. You can only label a poll like that with the benefit of hindsight and it might be that when we see further surveys that the poll carried out last weekend but only published today is spot on.
Having said that confidence in the Observer’s coverage of the findings would have been increased if the hugely important detail of the fieldwork timing had been highlighted – in fact it hardly gets a mention.
For the survey was carried out over precisely the same days as the ICM poll in the Observer’s sister paper, the Guardian, that was published on Tuesday. That also showed the same trend of a move to Labour but on nothing like the same scale of MORI.
The importance of poll timings was underlined during the conference season when YouGov produced its daily, 1,000 sample, tracker poll for Sky News. Each new poll brought dramatic swings and at one point Labour’s deficit dropped to just seven points. This all changed once the spotlight moved on from Brighton and polling settled down at the pre-conference season levels.
And a key factor at the start of the fieldwork period for last weekend’s ICM and MORI polls was Labour’s stunning victory in the Glasgow North East by election which was topping the bulletins just as the fieldwork was starting.
This is what wrote here BEFORE seeing either survey “….generally polls that are undertaken in the immediate aftermath of by elections give the winner a boost if only because of the extra exposure in the media…Theoretically at least this should be more marked in polls like ICM and MORI with heavy “certainty to vote†weightings. Supporters feel more encouraged and give a higher rating to the “how certain are you†question. MORI, of course, only includes the “100% certains†in its headline figures.”
One of the findings that will ease some of the Tory jitters is that Cameron’s personal satisfaction ratings with MORI are at their second highest since May. They stand at 48% satisfied to 35% dissatisfied. At the start of the year it was 44 – 38 and in September it was 45 – 39.