BPC/MRS Inquiry into the Performance of the Opinion Polls at the 2015 General Election

Terms of Reference

  1. To assess the accuracy of the published opinion polls (both national and sub-national) at the 2015 general election.
  2. To evaluate whether any inaccuracies identified might be part of a pattern evident at previous elections.
  3. To investigate the causes of any inaccuracies that are identified. Potential causes to be considered will include (but not necessarily be limited to): the possible impact of late changes in vote preferences, sampling methods, interview mode, weighting and filtering, population coverage, item refusal, differential availability and willingness to participate, question order and wording.
  4. To assess whether the analysis or reporting of polls was influenced by a reluctance to be out of line with the published figures of other polls.
  5. To consult and seek relevant evidence from all appropriate stakeholders, including but not exclusively, polling organisations that are members of the BPC.
  6. To assess whether adequate information was provided and communicated to interested commentators and the public about how  polls were conducted and what their results meant.
  7. To make, as it sees fit, recommendations for improving how opinion polls are conducted and published in future.
  8. To make recommendations, if necessary, for changing the rules and obligations of BPC membership.
  9. To submit a report to the BPC and MRS by 1 March 2016, with a view to its publication by BPC and MRS as soon as possible thereafter.