There are also health warnings that need to be put on the poll. Even the main question had a non-standard wording. (It's not a wording that in any way contained a pro-independence slant, but nevertheless the question should really have been 'Should Scotland be an independent country?') It appears from the datasets that the only political weighting in the poll was by recalled EU referendum vote. It's not unheard of for pollsters to eschew political weighting, but it's certainly unusual - the majority of firms would have weighted by recalled indyref vote and recalled general election vote. This is also Deltapoll's first foray into independence polling, which means there is no baseline to judge from. In other words, there is no hard evidence in this poll of a recent surge for Yes. The unusually good result may just be a 'house effect' generated by how the poll was conducted. That doesn't necessarily mean the figures are wrong - as Scottish Skier pointed out in the previous thread, it's perfectly possible that weighting by recalled indyref vote is making other firms' results less accurate, not more so. The fact that Ipsos-Mori (who don't weight politically) were a No-friendly firm before the indyref but are now more towards the Yes-friendly end of the spectrum might conceivably lend some weight to that theory.
But the bottom line is that if No-friendly firms like YouGov and Panelbase were to publish independence polls tomorrow, there's no reason to automatically think they'd show anything other than the type of No leads they usually show. So if we get too wedded to a narrative of "a referendum is coming because the polls now show a Yes lead", we're just setting ourselves up for a fall in very short order. The case for a referendum should not depend on whether Yes are currently at 43% or 47% or 49% or 52% - all of those are potential platforms for victory (or indeed for defeat). I'm particularly aghast to see Jason unintentionally echoing the rhetoric of those who want to see the referendum kicked into the long grass by stating that Yes now need to use their current momentum (which may not even exist) to kick on and reach an utterly fantastical and unattainable target figure of 60% by the date of Brexit, which is less than seven months away.
If we're serious about wanting an early referendum, we simply cannot afford to run away with ourselves and set unrealistic expectations of what the polls will show over the coming weeks and months. If a significant swing to Yes occurs, it's much more likely to be after the referendum is called, and not before.
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