Methodology changes
An update for methodology anoraks out there. ICM tweeted earlier today that they are to start doing part of their fieldwork using mobile phones. Up to now telephone pollsters in the UK have exclusively used landlines to conduct interviews (the actual process they use is to randomly select numbers, then randomise the last digit to catch ex-directory people).
As mobile phone ownership has became widespread landline ownership has peaked and begun to fall - Ofcom's figures are that 15% of adults live in a home that has a mobile, but no landline. This doesn't necessarily pose a problem for phone pollsters (after all, it is possible to conduct accurate polling on the internet and only 75% of UK adults have broadband access) it depends whether mobile only people are substantially different to landline people once you have controlled for all the demographics pollsters weight by (i.e. if doesn't matter if they are younger, or more middle class, as weighting would control for that)
Anyway, ICM at least are biting the bullet and starting to conduct 15% of their interviews over mobile phones. This has already become standard practice for many pollsters operating in other countries, but I think this may be the first of the regular pollsters in the UK to make the switch. Whether it makes any noticable difference or not I do not know.
A second change to note is ComRes, who have been experimenting with how they model likely turnout in their polls, and redistributing don't knows/won't says. I'm not sure of the exact details yet (Andrew Hawkins suggests it is still in flux) and Andrew tells me it is making "almost no difference to the outcome" but on their last two polls it seems to have made their figures marginally more Conservative. I'll do a further update once all becomes clear.
