Why the opinion polls were wrong in the 2015 general election | Letters

Disappointed Labour party supporters on 8 May 2015, the day after polling day.Both our research and the polling inquiry suggest that it was a failure to obtain representative samples that led to the 2015 polling miss and not people lying to pollsters or changing their minds at the last minute.In short, pollsters did not contact enough people from hard-to-reach groups that do not vote in elections.