AS POLLING errors go, this year’s misfire was not particularly large—at least in the national surveys. Mrs Clinton is expected to win the popular vote by a bit over one percentage point once all the ballots are counted, two points short of her projection. That represents a better prediction than in 2012, when Barack Obama beat his polls by three. But America does not choose its president by popular vote, and three of Donald Trump’s bigger outperformances occurred in states around the Great Lakes that proved decisive. Mrs Clinton led the polls in Wisconsin by five points, and in Michigan and Pennsylvania by four; Mr Trump is projected to claim them all, albeit by narrow margins. He did even better in Ohio, where he turned a two-point poll lead into an 8.5-point romp, and Iowa, where a three-point edge became a 9.5-point blowout.
While pollsters correctly gauged the sentiment of most slices of the electorate, they underestimated Mr Trump’s appeal to working-class whites. Although it was clear that he would run up the score with these voters, he managed to exceed even pollsters’ rosy expectations for him: projected to win them by 30...Continue reading
Source: United States http://www.economist.com/news/united-states/21710024-how-mid-sized-error-led-rash-bad-forecasts-epic-fail?fsrc=rss
EmoticonEmoticon