Latest YouGov / The Sun results 7th April - Con 33%, Lab 35%, LD 8%, UKIP 14%, GRN 5%; APP -11
From today until the general election YouGov's daily polling will move to seven days a week, including polling on Saturdays and Sundays. We are also altering our methods to put them on an election footing.
During peacetime YouGov does not usually take account of people's likelihood to vote - we simply include everyone who gives us a voting intention. As we approach the general election though we start to factor it into our calculations, so from today we are weighting people according to how likely they say they are to vote on May 7th.
In 2010 factoring in likelihood to vote increased the Conservative party lead by about a point. This year it does not, at present, seem to be making any significant difference to our headline figures at all, with Labour voters saying they are just as likely to turn out as Conservative voters.
YouGov are also returning to a method we successfully used in the 2005 general election. Our usual polling method relies upon weighting by party identification. However, for the campaign itself we will be drawing our daily polling samples from people who we previously contacted in January and February this year and weighting our data using how those people told us they were voting at that time (a period when the polls were broadly stable and Labour were, on average, slightly less than a point ahead).
This means that we can be confident that any material change in the polls from that position reflects a genuine shift in public opinion since January & February. There will be still be some random sample variation from poll to poll - it can never be eliminated completely - but it will mean any substantial change in the polls will be down to individual people changing their minds (or making their minds ups) since we interviewed them in February.