ICM post-debate poll

ICM did a rapid “who won” poll after the Paxman interviews with Cameron and Miliband tonight. Cameron won over Miliband by 54% to 46% – we won’t know until the tables appear, but I expect that going to show Labour voters thinking Miliband won, Conservative voters thinking Cameron won, the rest splitting evenly and not many minds changed. Still, we’ll see if there is any longer term effect in the next week’s polls. I wouldn’t have imagined there will be – while the debate was new in 2010, events like tonight’s Paxman interviews or the leaders’ Question Time style event next month aren’t new – there were things just like that in2005 and 2001 and they made bog all difference to anything.

Meanwhile tonight’s YouGov poll for the Sun has topline figures of CON 36%, LAB 34%, LDEM 7%, UKIP 13%, GRN 5%. A Tory lead today after some ties and Labour leads so far this week, suggesting the underlying average in YouGov’s daily polls is still neck-and-neck.

UPDATE: ICM tables are now up here (thanks to that fine man Tom Clark!). As expected, perceptions of who won fell pretty much along the lines of pre-existing party support – 84% of Conservatives thought Cameron won, 74% of Labour supporters thought Miliband won, Lib Dems were split, Ukippers thought Cameron won, Greens thought Miliband won. Note that while the sample was demographically and politically weighted to be nationally representative, it was a very heavily Labour sample in terms of current voting intention: the pre-debate voting intentions of the sample had an 10% Labour lead (thus are the difficulties of doing things like this – people who watch programmes like this are different from your average voter!)


Panelbase are well known for their Scottish polling, but today we have what I think is their first GB voting intention poll. Their first voting intention figures are CON 34%, LAB 34%, LDEM 5%, UKIP 15%, GRN 6%.

Apart from the low Lib Dem score the figures are very much in line with averages across all the pollsters (and it’s too early to tell if Panelbase will always tend to show low Lib Dem scores or this is just an unusual result.) The tables should be out later, but in terms of methodology Panelbase are internet based, they weight by recalled 2010 vote, they are filtering likely voters to include only those who rate their chances of voting at 8/10 or more, and they don’t do any reallocation of people who say don’t know.

UPDATE: The full tables for the Panelbase poll are here. They reveal one very unusual difference – this isn’t a GB poll at all, it’s a UK poll. The vast majority of political opinion polls are only of Great Britain and ignore Northern Ireland, given its different party system. Panelbase include it. It shouldn’t actually make much difference apart from bumping up the “Others” a bit to include the DUP, SDLP, Sinn Fein, UUP and so on and knocking down the mainland parties by a fraction.


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There have been several polls this week showing both the Conservatives and Labour up at 35%, and given it’s a zero sum game that suggests the other parties are getting squeezed. There is a general expectation of this sort of squeeze as the election approaches – the nature of First Past the Post is that votes for smaller parties don’t stand much chance of being translated into MPs unless they are geographically concentrated and as the election approaches the media coverage almost inevitably focuses ever more upon the main contenders (though more on that later).

The graph below shows the average poll scores for the Greens and UKIP across the nine regular pollsters (for those pollsters who do several polls a month, I’ve taken their average across the month).

greenandukip

UKIP have been on a slow but steady downwards trend since their support peaked after Douglas Carswell and Mark Reckless’s defections. This last month the decline may have flattened out a bit, but that is largely due to MORI having an unusually low score for them last month that jumped back up this month – without that the line would show a smoother downwards trend. The Green party’s advance seems to have halted last month and started to fade a little this month.

Of course, just because they might be getting squeezed shouldn’t distract from the fact that UKIP and the Greens are still doing incredibly well compared to the last election. In 2010 UKIP got 3%, the Greens 1% – both parties could suffer a bit more squeezing and still end up quadrupling the vote they got last time. For UKIP, there is also good news on the horizon, next week the campaign broadcasting restrictions kick in, guaranteeing them coverage as a major party. For most of the last few months UKIP’s media coverage has largely consisted of the latest row or resignation for inappropriate comments. Next week the broadcasters will have to start giving them more neutral coverage alongside the Conservatives, Labour and Lib Dems.

In other news, we had the monthly Survation poll for the Daily Mirror out today. Their topline figures were CON 32%, LAB 33%, LDEM 8%, UKIP 18%, GRN 4% (tabs.


There are two polls out tonight, both showing Labour and the Conservatives neck and neck on 35%. The first of ComRes’s more frequent telephone polls for the Daily Mail, ramped up to a weekly timetable for the election campaign, has topline figures of CON 35%, LAB 35%, LDEM 8%, UKIP 10%, GRN 7%. Meanwhile the daily YouGov poll for the Sun has extremely similar figures of CON 35%, LAB 35%, LDEM 8%, UKIP 12%, GRN 6%.


In this post back in January I wrote about the partisan effects of the different methodologies the different polling companies used, of how some companies tend to show consistently higher or lower scores for different parties. Since then I’ve been meaning to do a reference post explaining those different methods between pollsters. This is that – an attempt to do a summary of different companies methods in one place so you can check whether company A prompts for UKIP or what company B does with their don’t knows. As ever, this is from the published methodology details of each company and my own understanding of it – any mistakes are mine and corrections are welcome!

Phone polls

There are four regular telephone polls – Ipsos MORI, ICM, Ashcroft and ComRes/Daily Mail (ComRes do both telephone and online polls). All phone polls are conducted using Random Digit Dialing (RDD) – essentially taking phone numbers from the BT directory and then randomising the digits at the end to ensure the sample includes some ex-directory numbers, all polls will now also include some mobile phone numbers, though the pollsters have all said this makes little actual difference to results and is being done as a precaution. All telephone polls are weighted by some common demographics, like age, gender, social class, region, housing tenure, holidays taken and car ownership.

Ipsos MORI

Now the most venerable of the regular pollsters, Ipsos MORI are also the most traditional in their methods. They currently do a monthly political poll for the Evening Standard. Alone among GB pollsters they use no form of political weighting, viewing the problem of false recall as unsurmountable, their samples are weighted using standard demographics, but also by public and private sector employment.

MORI do not (as of March 2015) include UKIP in their main prompt for voting intention. For people who say don’t know, MORI ask who people who are most likely to vote for and count that equally as a voting intention. People who still say don’t know or won’t say are ignored. In terms of likelihood to vote, MORI have the tightest filter of any company, including only those respondents who say they are absolutely 10/10 certain to vote.

ICM

ICM are the second oldest of the current regular pollsters, and were the pioneer of most of the methods that became commonplace after the polling industry changed methods following the 1992 debacle. They currently do a monthly poll for the Guardian. They poll by standard demographics and by people’s past vote, adjusted for false recall.

ICM don’t currently include UKIP in their main voting intention prompt. People who say they don’t know how they will vote are reallocated based on how they say they voted at the previous election, but weighted down to 50% of the value of people who actually give a voting intention. In terms of likelihood to vote, ICM weight by likelihood so that people who say they are 10/10 certain to vote are fully counted, people who say they are 9/10 likely to vote count as 0.9 of a vote and so on. Additionally ICM weight people who did not vote at the previous election down by 50%, the only pollster to use this additional weighting.

Ashcroft

Lord Ashcroft commissions a regular weekly poll, carried out by other polling companies but on a “white label” basis. The methods are essentially those Populus used to use for their telephone polls, rather than the online methods Populus now use for their own regular polling. Ashcroft polls are weighted by standard demographics and by past vote, adjusted for false recall.

Ashcroft’s voting intention question has included UKIP in the main prompt since 2015. People who say they don’t know how they will vote are reallocated based on how they say they voted at the previous election, but at a different ratio to ICM (Ashcroft weights Conservatives and Labour down to 50%, Lib Dems down to 30%, others I think are ignored). In terms of likelihood to vote, Ashcroft weights people according to how likely they say they are to vote in similar way to ICM.

ComRes

ComRes do a monthly telephone poll, previously for the Independent but since 2015 for the Daily Mail. This is separate to their monthly online poll for the Independent on Sunday and there are some consistent differences between their results, meaning I treat them as two separate data series. ComRes’s polls are weighted using standard demographics and past vote, adjusted for false recall – in much the same way as ICM and Ashcroft.

ComRes have included UKIP in their main voting intention prompt since late 2014. People who say they don’t know how they will vote or won’t say are asked a squeeze question on how they would vote if it was a legal requirement, and included in the main figures. People who still say don’t know are re-allocated based on the party they say they most closely identify with, though unlike the ICM and Ashcroft reallocation this rarely seems to make an impact. In terms of likelihood to vote ComRes both filter AND weight by likelihood to vote – people who say they are less than 5/10 likely to vote are excluded completely, people who say they are 5/10 to 10/10 are weighted according to this likelihood.

Online Polls

Online poll sampling can be somewhat more opaque than telephone sampling. In most cases they are conducted through existing panels of online volunteers (either their own panels, like the YouGov panel or PopulusLive, or panels from third party providers like Toluna and Research Now). Surveys are conducted by inviting panellists with the required demographics to complete the poll – this means that while panels are self-selecting, surveys themselves aren’t (that is, you can choose to join a company’s online panel, but you can’t choose to fill in their March voting intention survey, you may or may not get randomly invited to it). Because panellists demographics are known in advance, pollsters can set quotas and invite people with the demographics to reflect the British public. Some pollsters also use random online sampling – using pop-ups on websites to randomly invite respondents. As with telephone polling, all online pollsters use some common demographic weighting, with all companies weighting by things like age, gender, region and social class.

YouGov

YouGov are the longest standing online pollster, currently doing daily voting intention polls for the Sun and Sunday Times. The length of time they have been around means they have data on their panellists from the 2010 election (and, indeed, in some cases from the 2005 election) so their weighting scheme largely relies on the data collected from panellists in May 2010, updated periodically to take account of people who have joined the panel since then. As well as standard demographics, YouGov also weight by newspaper readership and party identification in 2010 (that is, people are weighted by which party they told YouGov they identified with most in May 2010, using targets based on May 2010).

YouGov have included UKIP in their main prompt since January 2015. They do not use any weighting or filtering by likelihood to vote at all outside of the immediate run up to elections (in the weeks leading up to the 2010 election they weighting by likelihood to vote in a similar way to Ashcroft, Populus and ICM). People who say don’t know are excluded from final figures, there is no squeeze question or reallocation.

Populus

Populus used to conduct telephone polling for the Times, but since ceasing to work for the Times have switched to carrying out online polling, done using their PopulusLive panel. Currently they publish two polls a week, on Mondays and Fridays. As well as normal demographic weightings they weight using party identification, weighting current party ID to estimated national targets.

Populus have included UKIP in their main prompt since February 2015. They weight respondents according to their likelihood to vote in a similar way to ICM and Ashcroft. People who say don’t know are excluded from final figures, there is no squeeze question or reallocation.

ComRes

Not to be confused with their telephone polls for the Daily Mail, ComRes also conduct a series of monthly online polls for the Independent on Sunday and Sunday Mirror. It is conducted partially from a panel, partially from random online sampling (pop-ups on websites directing people to surveys). In addition to normal demographic weightings they weight using people’s recalled vote from the 2010 election.

ComRes have included UKIP in their main prompt since December 2014. Their weighting by likelihood to vote is slightly different to their telephone polls – for the Conservatives, Labour and Liberal Democrats it’s the same (include people who say 5+/10, and weight those people according to their likelihood) but for UKIP and Green I believe respondents are only included if they are 10/10 certain to vote. Their treatment of don’t knows is the same as in their phone polls: people who say they don’t know how they will vote or won’t say are asked a squeeze question and included in the main figures, people who still say don’t know are re-allocated based on the party they say they most closely identify with.

Survation

Survation do a regular poll for the Daily Mirror and occasional polls for the Mail on Sunday. Data is weighted by the usual demographics, but uses income and education rather than social class. Recalled 2010 vote is used for political weighting. Survation have included UKIP in their main prompt for several years. They weight by likelihood to vote in the same way as ICM, Populus and Ashcroft. People who say don’t know are reallocated to the party they voted for in 2010, but weighted down to 30% of the value of people who actually give a voting intention.

Note that Survation’s constituency polls are done using a completely different method to their national polls, using telephone sampling rather than online sampling and different weighting variables.

Opinium

Opinium do regular polling for the Observer, currently every week for the duration of the election campaign. Respondents are taken from their own panel and is weighted by standard demographics. Historically Opinium have not used political weighting, but from February 2015 they switched to weighting by “party propensity” for the duration of the election campaign. This is a variable based on which parties people would and wouldn’t consider – for practical purposes, it seems to be similar to party identification.

Opinium do not include UKIP in their main prompt (meaning they only appear as an option if a respondent selects “other”). They filter people by likelihood to vote, including only respondents who say they will definitely or probably vote. People who say don’t know are excluded from the final figures.

TNS

TNS are a huge global company with a long history in market research. In terms of public opinion polling in this country they are actually the successors to System Three – who used to be a well known Scottish polling company and ended up part of the same company through a complicated series of mergers and buy-outs by BMRB, NFO, Kantar and WPP, currently their ultimate parent company. At the last election TNS were the final company doing face-to-face polling, since then they have switched over to online. The sample is taken from their Lightspeed panel and is weighted using standard demographics and recalled 2010 vote. TNS do include UKIP in their main prompt, and also prompt for the BNP and Green. TNS filter and weight people according to likelihood to vote and exclude don’t knows and won’t says from their final figures.

Putting all those together, here’s a summary of the methods.

methods2

As to the impact of the different methods, it not always easy to say. Some are easy to quantify from published tables (for example, ICM and Ashcroft publish their figures before and after don’t knows are reallocated, so one can comfortably say “that adjustment added 2 points to the Lib Dems this week”), others are very difficult to quantify (the difference the choice of weighting regimes makes is very difficult to judge, the differences between online and telephone polling even more so), many methods interact with one another and the impacts of different approaches changes over time (a methodology that helps the Tories one year may help the Lib Dems another year as public opinions change). Rather than guess whether each pollsters methods are likely to produce this effect or that effect, probably best to judge them from actual observed results.

UPDATE:
TNS have confirmed they do prompt for UKIP, and also prompt for the BNP and Green – I’ll update the table later on tonight.