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Web Survey Bibliography

Title The Failure of the Polls: Lessons Learned from the 2015 UK Polling Disaster
Year 2017
Access date 05.04.2017

The result of the 2015 UK General Election came as a shock to most observers. During the months and weeks leading up to the 7th May, the opinion polls had consistently indicated that the outcome was too close to call and the prospect of a hung parliament appeared almost inevitable. Although there was some variation across pollsters in their estimates of the party vote shares during the short campaign, estimates of the difference between the Conservative and Labour Parties exceeded two percentage points in only 19 out of 91 polls, with zero as the modal estimate of the Conservative lead.

A feature of the 2015 election was the very high volume of polls undertaken; between 1945 and 2010 there were a total of approximately 3,000 election polls in Britain, compared to 1,942 between 2010 and 2015. This rapid expansion is almost entirely due to the emergence of opt-in internet surveys, which have massively reduced the unit cost of an interview.

In this presentation, I shall draw on the findings of the Inquiry into the British General Election opinion polls, as well as analysis of the EU referendum polls to consider what can be learned for opinion polling and survey methodology more broadly.


Year of publication2017
Bibliographic typeConferences, workshops, tutorials, presentations