Monday, October 5, 2015

A surfeit of surprises

Those of you who are a bit older than me will probably recall the very likeable David Butler, who was the BBC's resident psephologist on every general election results programme between 1950 and 1979.  (The rest of us can catch up via the wonders of YouTube, although unfortunately no recording exists of 1950 or 1951.)  He invented the whole concept of 'swing', and in the days before exit polls was famous for extrapolating the swing from the early declarations to give viewers the first indication of which party was likely to take power.

I was intrigued to spot a lengthy quote from Butler in Antifrank's new article at Stormfront Lite, in which he argues that this year's polling disaster was not some kind of weird exception, and that the polls in fact get it wrong at general elections more often than not.  I think his broad point is absolutely right, but he seems to be over-egging the pudding with some of his specific examples...

"In three elections (’45, ’66 and ’97) there was a Labour victory of totally unexpected proportions."

In 1997, the polls actually overestimated Labour's lead, rather than underestimated it.  If the scale of Blair's majority took most people by surprise, that was because 1992 was fresh in their minds, and they simply refused to believe the evidence of their own eyes.

In 1945, polling was in its infancy, and the expectations that Churchill would be rewarded for leading Britain through the war had nothing whatever to do with polls.  (There was some polling evidence of a handsome Labour lead, but it was largely ignored.)

"In three others (’50, ’64 and October ’74) an expected Labour victory was achieved by only a single-figure margin."

Again, it's doubtful that the expectations of a solid Labour majority in 1950 had much to do with opinion polls.

"And in two elections (February ’74 and 2010) there was a hung parliament that few anticipated."

Few anticipated a hung parliament in February 1974, but in 2010 the polls pointed overwhelmingly to that outcome.  It's true that the betting odds favoured a Conservative overall majority (and apparently Conservative Central Office shared that view), but that was because Tory-leaning punters thought they knew better than the polls.  Ironically, they were expecting a 2015-style outcome five years too early.

So, of the general elections that have occurred since opinion polls started to be taken seriously, which ones can be classed as genuine "shocks"?  I'd say there are five -

1970 : This is perhaps the all-time classic, because the polls pointed to a comfortable Labour overall majority, but the outcome was a comfortable Conservative overall majority.  There was a much bigger risk of that sort of thing happening back in those days - Britain was almost a pure two-party system (the Ulster Unionists still took the Tory whip, and Liberals and nationalists were very few in numbers).  So if the polls were wrong about one party securing a majority, it was fairly likely that the other party would do so.

February 1974 : The polls pointed to a Conservative majority, but Labour emerged by a whisker as the largest single party in a hung parliament, and were able to form a minority government.

October 1974 : The polls pointed to a handsome Labour majority (possibly even a landslide), but in the end Harold Wilson was lucky to barely scrape the tiniest of tiny majorities, which was soon wiped out by defections and by-election defeats.

1992 : The polls pointed to a hung parliament.  It wasn't at all clear whether Labour or the Tories would be the largest single party, but the assumption was that a Labour-led government of some description was likely to emerge, because a Tory-Lib Dem deal seemed highly improbable.  But the actual outcome was a modest Conservative overall majority.

2015 : Almost an exact repeat performance of 1992, other than the fact that the permutations for the expected hung parliament were much more numerous and complicated.  They all proved to be academic as the Tories emerged with a slim outright majority of 12.

So five major shocks in the last twelve elections, which is still a pretty significant proportion.  That, of course, is a big part of the reason why "tactical voting on the list" in next year's Holyrood election is such a mug's game.  The idea that it's even feasible depends on wildly unrealistic assumptions of extreme polling accuracy.  You'd think that people would know better after what happened only five months ago, but apparently not.

*  *  *

After quoting Butler, Antifrank goes on to make a series of observations about how opinion polls should be sensibly interpreted.  You won't be surprised to hear that I disagree with this one -

"Ignore subsamples. They aren’t weighted and the numbers are so small as to be meaningless (often they are actively misleading). Don’t waste your time on them."

If we had ignored the Scottish subsamples from GB-wide polls at this time last year (as, it has to be said, John Curtice studiously did), we'd have been completely unaware that the SNP surge was taking place.  They were showing a very clear trend, and we had no other information to go on - apart from a single Panelbase poll that turned out to be slightly dodgy.

Yes, subsamples have to be treated with extreme caution, and individual subsamples can sometimes be worse than useless.  But if there is literally no other data out there, aggregates of subsamples are better than nothing, and can at least give you some kind of vague sense of what's going on.  We're in a situation like that right now - we've had no full-scale Scottish polls since Jeremy Corbyn became Labour leader, but the subsamples suggest he hasn't made much of an impact north of the border.  We'll discover soon enough whether that's misleading.

35 comments:

  1. James

    The council elections last Thursday are better than any sub-sample.

    No unionist party won a seat on Thursday. Not a straw in the wind, a hurricane.

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    1. No, I don't agree with that, actually. The council elections were in line with what we had seen between May and September, but that covers quite a broad range.

      What happened on Thursday was unambiguously bad for Labour, but it's harder to interpret the SNP's results. As I said in my post at the time, on a simple projection their national share of the vote would have been just 39%. That's probably misleadingly low due to a number of factors, but exactly how misleading is anyone's guess.

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    2. Both subsamples and by-elections are two different pieces of information, which help to build up a picture of what may be happening. Both come with their own sets of problems, which have to be remembered in deciding how much weight you place on the information (e.g. how much it contributes to building up that picture). The by-election results were roughly what one might expect for the SNP, and the most interesting feature was perhaps the suggestion of a small swing from Labour to the Conservatives. This has also been suggested by a succession of subsamples from UK polls putting the Conservatives ahead of Labour. The next Scotland poll may confirm that something like this is happening, or it may just be random noise.

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    3. "unambiguously bad for Labour..."


      I'll take that. Thoroughly deserved!

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  2. There seems to be a few subsamples putting tories ahead of labour in Scotland. The most recent YouGov subsample also shows a majority (51%) now plan to vote for parties of the union as opposed to 49% for the SNP/Green/Socialist mob. If that happened in a purely proportional parliament, the SNP would be humbled - perhaps even ejected from office. Unfortunately, that's not the system we operate.

    I do expect Holyrood 2016 to be a close run thing however - and if enough yessers feel free to vote for Greens etc, then there could yet be a big upset in store.

    And for anyone who doubts the volatility of Scottish public opinion, just think back to late 2010 and how Iain Gray looked a dead cert!

    Aldo

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    1. Yes, but Nicola Sturgeon isn't exactly Iain Gray. For clarity, you disagree with your party leader and think that proportional representation is a good thing? Because what you seem to be proposing is the most proportional system in the entire world - not even the smallest of minimum thresholds for representation.

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    2. What you also seem to be advocating is perpetual independence referendums. The new tory policy?

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    3. What a spurious argument. I estimate that 500,000 Naw voters at least couldn't be bothered voting at the Brit GE and you would have thought that would be far more important for the Naw heids than the wee pretendy Parly in Edinburgh. You completely ignore that the Naw gangster Parties will split the Naw vote as well. Oh and the Red Tories and the Blue Tories along with the Orangey Tories are fighting over a declining vote. UKIP the purple Unionist gangsters will further split the Naw gangs vote.

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    4. I think a proportional system is necessary where such a deep and important constitutional divide is present. I don't think it's sustainable to have the losers of a referendum able to call a rerun whenever they wish.

      Aldo

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    5. There's an obvious answer to that.The unionist parties should form an alliance in Scotland.Under Kez,Ruth or Willie.A broad church party of the Union.

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    6. I have a feeling that wont be necessary. The SNP already has a stench of decay surrounding it. Scandal, spin and lies being exposed - increasingly absurd and shouty pro indy rallies attended by one man and his dog. The whole thing is turning manky quicker than a morbidly obese person on a hot summer's day. Should the gargantuan SNP lead continue for years, a unionist political force - united and moderate - will be required. But not yet :0)

      Aldo

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    7. "a unionist political force - united and moderate - will be required"

      Well, that rules you out, old chap.

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    8. Compromise would be required. I would compromise with a socialist to maintain the union - and so would most conservatives.

      For, if we don't, we quite possibly lose our country and end up like Venezuela. Avoiding that is well worth taking a back seat to a labour dominated electoral alliance.

      Aldo

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    9. Compromise won't make you a moderate, Aldo. I'll never forget what you said about the innocent victims of the Hiroshima bombing.

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    10. That's mainstream opinion though - that the Japanese brought the situation on themselves and that, in total war, destruction of the enemy is the number one consideration.

      Had the shoe been on the other foot, do you think the Japanese would have been reluctant to nuke British cities?

      Japan is now a highly advanced, civilised country with many admirable traits. It may well not have been had we been forced to fight town by town, street by street.

      Aldo

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    11. No, Aldo, taking extreme pleasure in the mass slaughter of children is not "mainstream opinion". Grow up.

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    12. That's not what I did though. I believe my exact words were "such vile acts cry out for retribution" (in reference to the Japanese torture and murder spree across the Pacific). I think many people would probably agree.

      The guy who got his tongue and balls cut off would definitely agree.

      Aldo

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    13. "I believe my exact words were "such vile acts cry out for retribution""

      So you believe burning thousands of children to death was justified as "retribution"? This is what you believe and are proud to stand by?

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    14. It wasn't just children though was it? Those cities hosted adults, soldiers, potential soldiers and elements of the war machine. It's regrettable when innocents have to die. But that's life unfortunately - bad things happen. Not in SNP / Corbyn world though - where all is sweetness and light, hope triumphs over fear blah blah.

      I think I had outgrown those beliefs by the age of ten.

      Aldo

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    15. Oh, yes, who cares if we kill thousands of children - we certainly mustn't let our squeamishness get in the way of killing adults as "retribution".

      That's called "maturity" on Planet Aldo.

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  3. I predict that this whole smeargate is going to backfire. It might in the long run increase the SNP vote. I fuly expect the sham to be publically exposed as a dirty game played out by the media.

    Expect Ruth and Kezia to find themselves in hot water and be hawled in front of the standards committee.

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    1. Personally I'm expecting a by election in Edinburgh West.

      Aldo

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    2. That would be the ideal opportunity for a unionist alliance to contest a seat.Or maybe for some of the unionist parties to stand aside,in order to keep the SNP out.

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    3. By-elections can prove very elusive when you're just waiting and hoping for an MP to resign. (But maybe not quite as elusive as that "unionist alliance".)

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  4. In an Elections and Voting in Britain class I took as an undergraduate in 2007/8, the lecturer predicted there would be a hung parliament in 2010 some three years before the 2010 election and seemed pretty confident about it as well. So to say that no-one predicted it is as erroneous as James suggests.

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  5. Average of every Scottish subsample since the election:
    51% - SNP
    20% - Conservative
    18% - Labour
    5% - Lib Dem
    3% - UKIP; Green

    Something must be happening for the Tories to be polling around the same as Labour...

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  6. How can there still be 20% Tories in Scotland? I just can't fathom it.

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    1. Glasgow Working ClassOctober 5, 2015 at 11:54 PM

      It is because the total is calculated thus, Tartan Tories + Real Tories = 20%.

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    2. The tory vote would be considerably higher, if Scotland had to pay for its own socialism.

      Aldo

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    3. Maybe it's so low because we have to pay for another country's Thatcherism.

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  7. Glasgow Working ClassOctober 6, 2015 at 1:35 AM

    James you are a youngster a Thatcher baby. Your Nat sis helped her tae power. Time the Nat sis admitted to their collaboration and stopped their false anti Tory rhetoric.

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    1. I'm not a Thatcher baby, as it happens. Are you a Gladstone baby?

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  8. Glasgow Working ClassOctober 6, 2015 at 1:58 AM

    Naw just Clement.

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