The benefits of random sampling
Lessons from the 2015 UK General Election
Published: January 2016
This paper presents data from the 2015 British Social Attitudes survey on reported voting behaviour in the 2015 General Election. It explores why these data are more accurate than the opinion polls that took place before the election in replicating what actually happened at the election - both in terms of voter turnout and levels of support for the main political parties.
- Data from the British Social Attitudes survey suggest that unrepresentative samples caused the General Election polling error.
- Data on reported voting from BSA 2015 show a Conservative lead over Labour of 6.1 points, very close to the actual lead recorded at the 2015 General Election of 6.6 points.
- 70% of BSA respondents reported voting at the General Election, close to the official turnout figure of 66%.
This paper analyses data on reported voting behaviour in the 2015 UK General Election, collected as part of the 2015 British Social Attitudes survey. Data relating to the number of calls survey interviewers made to secure interviews at selected addresses were also analysed in order to examine the relationship between ease of participant recruitment and reported voting behaviour.
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