Opinion polls yadda yadda. OR “Does Nate Silver mean nothing to you? Did he write in vain?”

by Stephen Tall on May 21, 2013

Two new polls last night: the daily YouGov tracker and the first post-local elections poll from Survation. The spread is interesting:

    Labour: 35% (Survation 39% (YouGov)
    Conservatives: 24% (S), 31% (YG)
    Lib Dems: 11% (S), 10% (YG)
    Ukip: 22% (S), 14% (YG)

As Anthony Wells points out, Survation asks whether people will vote Ukip (most other firms just ask about the main three parties and ‘Others’) so usually gets the highest Ukip poll numbers. This latest survey is in line with the bounce other firms have shown and which the perceived winner of an election often records.

Unsurprisingly, it’s Survation’s poll which has attracted most interest because it shows a gap if just 2% between the Tories and Ukip. Cue cries of ‘Tory meltdown!, ‘Cameron in crisis!’ and every other journalistic cliche.

At the risk of precipitating on the parade of those who love nothing better than to indulge in over-excited hyper-speculation, can I make the following point. Or rather can I ask the following question: Does Nate Silver mean nothing to you? Did he write in vain?

nate-silver-flickrOne of the very simple — I mean it: really simple — points he made in the run-up to the last US presidential election was that national poll ratings are not the best way of judging who was most likely to emerge the winner. Throughout that election campaign journalists and commentators (who are paid to understand this stuff and enlighten the public) termed the contest a ‘dead-heat’ on the basis that national polls showed a consistent but narrow Obama lead that was within the margin of error. Yet Nate Silver’s analysis of individual state polls showed Obama with an unwaveringly firm hold on the US electoral college.

Nate’s confident prediction was acclaimed here in the UK. Yet the lessons for us here are now routinely ignored. Just as the US decides its President through an electoral college, we decide our government through electing constituency MPs. The only way to work out who’s actually most likely to form the next government is to undertake more regional polling and then to extrapolate from that the likely number of MPs for each party, while also weighting for other facts such as incumbency boosts (which disproportionately aid the Lib Dems and first-term MPs). But, as I wrote last November:

The blunt reality is that the news media craves excitement more than it hungers for truth. It is much cheaper and easier to commission a monthly survey and then inflate the results way beyond what the data should allow. We’ve all seen the kinds of headlines newspapers revel in — ‘Poll blow to Tories as support plunges 1%’, ‘Labour to win 100+ majority says latest exclusive poll’ — and yet journalists continue to write them even though they know deep down how flimsy the evidence is.

I’ve read lots of adulation of Nate Silver in the British media in the past 24 hours. I wonder if any of those journalists who’ve penned those articles have thought, even for a moment: I wish I had the confidence to write about polls with the same kind of rigour he does. I’m not holding my breath.

(I’m glad I didn’t hold my breath.)

The reality is that first-past-the-post entrenches the status quo. If the Survation poll were actually to be reflected at a general election, then Ukip would (at least according to Electoral Calculus’s predictor) gain one MP in return for their 22% of the vote. Shades of the Liberal/SDP Alliance in 1983. Labour would win a majority of 122. (And for those who half-wish for such an outcome to show up the bankruptcy of our electoral system, let’s remember: the same prophesies were made in the 1980s, and 30 years later we’re still nowhere nearer to winning that argument.)

The easiest thing to write about the next election is that “it’s completely unpredictable”. That’s only half-true, though. For sure, we don’t know if the Ukip-mania will last for another two years; and if it does quite how that will play out in relation to the Tory/Labour/Lib Dem votes. That is unpredictable. But we can be sure that Ukip won’t storm the House of Commons. The Ukip phenomenon is interesting in all sorts of ways. But as for the next House of Commons, Plaid Cymru is more significant than Ukip will be.

* Stephen Tall is Co-Editor of Liberal Democrat Voice, a Research Associate for the liberal think-tank CentreForum, and also writes at his own site, The Collected Stephen Tall.