So much for Euan McColm's hints that there was bad polling news for Yes coming tonight. Hot on the heels of the sensational ICM poll that put the Yes campaign 8% ahead, we now finally have the first signs that what we used to call the "most Yes-friendly pollster" is picking up the same pro-Yes swing as everyone else (with the possible exception of Survation).
Should Scotland be an independent country?
Yes 49.4% (+1.9)
No 50.6% (-1.9)
For obvious reasons that will be rounded down to 49/51 for publication, but in fact those results are virtually identical to the TNS-BMRB poll, which was rounded up to 50/50.
With the exception of one poll from last September that is generally disregarded because of an unusual question sequence, this is the best poll for Yes that Panelbase have ever published. Although they've tended to produce much more modest shifts than other pollsters, it has to be borne in mind that they've made a number of small methodological changes which have probably had a cumulative No-friendly effect, so the progress that Yes have had to make to reach 49% may well be slightly more substantial than would appear to be the case at a casual glance.
Of course there was a time not too long ago when a poll like this would have been greeted by No supporters with a dismissive "it's only Panelbase" and a shrug of the shoulders. That won't work anymore - Panelbase have well and truly 'slipped back into the pack', and their results now look positively mainstream. Three out of seven BPC pollsters now agree that Yes are on 49% or higher, and five out of seven agree that they are on 47% or higher. (One of the other two doesn't really count, because Ipsos-Mori haven't published a poll since the evening of the first leaders' debate.)
I'm now going to embark on the mammoth task of analysing the other three of today's four polls (or of falling asleep - whichever happens first), but to make matters easier I'll start by copying-and-pasting something I've just written on the previous post about Yes taking the lead with ICM...
I just want to deal with a point about the ICM poll that has already been discussed at length in the comment section below and elsewhere. It is categorically not the case that it should be regarded as a lesser poll because it had a slightly lower sample size than usual (705 as opposed to the more typical 1000). According to the very handy MOE calculator on the ComRes website, the margin of error for a poll of 700 respondents is approximately 3.7% - which is only fractionally higher than the 3% margin of error for a poll of 1000. Someone suggested below that I have said in the past that, by definition, polls of this size cannot be regarded as statistically reliable. I've never said that, because it isn't true. The only thing I can think of is that I put a health warning on YouGov "polls" of roughly this size in the run-up to the European elections, but that's because they weren't proper polls - they were aggregates of subsamples from GB-wide polls. The key factor in determining whether a poll is legitimate is not the sample size (unless it is absurdly small) but rather whether it was properly weighted. As far as I know, this one was weighted in exactly the same way as any other ICM online poll would be - I'm quite sure Professor Curtice would have been the first to flag it up if that had not been the case. So it should be regarded as a legitimate ICM online poll in exactly the same way as any other ICM online poll.
Indeed, we've had smaller polls than this during the campaign - two of the three Angus Reid polls that were published last year had samples of 500 or so, and although that fact was noted in passing, it wasn't perceived as significantly detracting from the credibility of the results. In the US, samples of 500 would be regarded as fairly routine, and it would certainly be seen as very odd to use that as an excuse for ignoring any given poll. And what about the ICM poll with a sample of 500 which the media seized upon as 'absolute proof' that Alistair Darling had defeated Alex Salmond in the first debate? I don't recall Euan McColm casting doubts on the reliability of that one. (I did, as it happens, as did Professor Curtice to some extent, but that was mostly because of the extreme upweighting that had gone on.)
It's therefore extremely troubling that the title Curtice uses for his blogpost on the ICM poll is "ICM Put Yes Ahead - Perhaps". Does the "perhaps" refer to the 3.7% margin of error? If so, shouldn't any verdict on any standard poll of 1000 people also automatically have the word "perhaps" attached to the title, because all of those polls have margins of error of 3%? Or is there some kind of mystical gulf between the numbers 3 and 3.7 that I've failed to comprehend so far? It just seems like a ludicrous double-standard. I note that a report on the BBC website is mentioning all of the other polls today, but not the ICM one - I can't help wondering if that's been caused by a misinterpretation of Curtice's title as meaning that this is somehow not a "proper poll". By the way, I have no complaint about Curtice's decision to add this poll to his Poll of Polls, but to give it a slightly lower weighting in proportion with the sample size - that seems perfectly reasonable to me. But it should also be seen absolutely, unambiguously as an endorsement of the poll's legitimacy, because that's exactly what it is.
You probably don't need me to point out that you would have to go to the extreme end of a 3.7% margin of error to take this poll to a result that does not have Yes clearly in the lead. Given the strength of the evidence from other pollsters that No are either slightly ahead or level, perhaps we do need to assume that ICM have produced a result that is at the extreme end of the margin of error, but so what? We could be forgiven for making exactly the same assumption about today's Survation poll, which is showing a lower Yes vote than others.
On the previous thread, Keaton makes the point that the ICM poll looks very much like an extreme outlier. I wouldn't necessarily disagree with that, but that doesn't mean that its publication shouldn't affect our perception of the state of play. Look at it this way : other recent polls say that the Yes vote is somewhere between 46 and 51. If the true position was closer to 46 than to 51, you'd expect that any extreme outlier poll that came along would put them on something like 43, rather than 54. So if nothing else, ICM have certainly bolstered the impression of a race that is very close to being even-stevens. A crude average of the rounded numbers from today's four polls gives a position of Yes 48.5%, No 51.5%.
It should also give us heart that the ICM fieldwork started one day later than the same firm's telephone poll started, and finished one day later than the telephone poll finished. That may not seem like a huge difference, but the scare stories have literally been ratcheting up with every passing day, so it's important to have some kind of evidence that the electorate resisted them until at least Friday. Unfortunately, the most apocalyptic of all the 'warnings' - very much of the "YOUR CHILDREN WILL ALL DIE IN HORRIBLE AGONY IF YOU VOTE YES" variety - is not really factored into any of the polls so far, so we have to bear that in mind. It's hard to believe that noble, selfless intervention into our democratic process won't have had any negative effect at all, but we'll see.
Let's turn now to the Survation telephone poll, which of course was commissioned by the No campaign, and only published after they decided the numbers were sufficiently to their liking (heaven only knows how many unpublished polls they've commissioned over the last couple of weeks). As Calum Findlay pointed out straight away, Yes only ended up being rounded down to 46% by the tiniest of margins, and it's intriguing to speculate whether the poll would ever have seen the light of day if the coin toss had gone the other way, and Yes had been rounded up to 47%. My guess is that it wouldn't. In any case, it was only on the turnout-weighted figures that Yes were rounded down - among the whole sample, the poll shows a position of Yes 46.7%, No 53.3%.
It's also somewhat chastening for the No campaign to find themselves voluntarily publishing a poll which shows that undecided voters are more likely to break for Yes. Whatever happened to the claim that the recent swing to Yes had only occurred because the undecideds who were willing to "take a leap" had already done so, while the remaining hard-core of undecideds were heavily No-leaning? When 'undecided leaners' are added to the voting intention figures for the whole sample (there isn't enough information to add them to the turnout-weighted figures), the position improves to Yes 47.1%, No 52.9%.
Although the Opinium poll was, to use Kenny Farquharson's favourite term, "independently commissioned" and would have been published whatever the results had been, it shows quite a similar story to Survation, in that rounding has made the published figures less favourable to Yes. The unrounded figures are Yes 47.4%, No 52.6%, and without the very strict Ipsos-Mori-style turnout filter being applied, they would be Yes 47.9%, No 52.1%.
* * *
Swing required for 1 out of 7 pollsters to show Yes ahead or level : 0.0%
Swing required for 3 out of 7 pollsters to show Yes ahead or level : 0.5%
Swing required for 4 out of 7 pollsters to show Yes ahead or level : 2.0%
Swing required for 5 out of 7 pollsters to show Yes ahead or level : 2.5%
Swing required for 6 out of 7 pollsters to show Yes ahead or level : 3.5%
Swing required for 7 out of 7 pollsters to show Yes ahead or level : 7.0%
* * *
SCOT GOES POP POLL OF POLLS
Opinium are a fully-fledged BPC-affiliated polling firm, so with this update of the Poll of Polls we move back to using an average of seven firms for the first time since Angus Reid were removed in the spring due to inactivity.
MEAN AVERAGE (excluding Don't Knows) :
Yes 48.1% (+1.1)
No 51.9% (-1.1)
MEAN AVERAGE (not excluding Don't Knows) :
Yes 43.6% (+2.1)
No 47.1% (+0.3)
MEDIAN AVERAGE (excluding Don't Knows) :
Yes 47.9% (+0.3)
No 52.1% (-0.3)
(The Poll of Polls is based on a rolling average of the most recent poll from each of the pollsters that have been active in the referendum campaign since September 2013, and that adhere to British Polling Council rules. At present, there are seven - YouGov, TNS-BMRB, Survation, Panelbase, Ipsos-Mori, Opinium and ICM. Whenever a new poll is published, it replaces the last poll from the same company in the sample. Changes in the Poll of Polls are generally glacial in nature due to the fact that only a small portion of the sample is updated each time.)