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Exit polling in a cold climate : the BBC-ITV experience in Britain in 2005

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Curtice, John and Firth, David. (2008) Exit polling in a cold climate : the BBC-ITV experience in Britain in 2005. Journal Of The Royal Statistical Society Series A-Statistics In Society, Vol.171 (No.3). pp. 509-539. ISSN 0964-1998

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Official URL: http://dx.doi.org/10.1111/j.1467-985X.2007.00536.x

Abstract

Conducting an exit poll to forecast the outcome of a national election in terms of both votes and seats is particularly difficult in Britain. No official information is available on how individual polling stations voted in the past, use of single-member plurality means that there is no consistent relationship between votes and seats, electors can choose to vote by post and most of those who vote in person do so late in the day. In addition, around one in every six intended exit poll respondents refuses to participate. Methods that were developed to overcome these problems, and their use in the successful 2005 British Broadcasting Corporation-Independent Television exit poll, are described and evaluated. The methodology included a panel design to allow the estimation of electoral change at local level, coherent multiple-regression modelling of multiparty electoral change to capture systematic patterns of variation, probabilistic prediction of constituency winners to account for uncertainty in projected constituency level shares, collection of information about the voting intentions of postal voters before polling day and access to interviewer guesses on the voting behaviour of refusals. The coverage and accuracy of the exit poll data are critically examined, the effect of key aspects of the statistical modelling of the data is assessed and some general lessons are drawn for the design and analysis of electoral exit polls.

Item Type:	Journal Article
Subjects:	J Political Science > JN Political institutions (Europe) > JN101 Great Britain Q Science > QA Mathematics
Divisions:	Faculty of Science > Statistics
Library of Congress Subject Headings (LCSH):	Exit polling (Elections) -- Methodology, Elections -- Great Britain -- Statistics, Elections -- Great Britain -- Mathematical models
Journal or Publication Title:	Journal Of The Royal Statistical Society Series A-Statistics In Society
Publisher:	Blackwell Publishing
ISSN:	0964-1998
Date:	June 2008
Volume:	Vol.171
Number:	No.3
Number of Pages:	25
Page Range:	pp. 509-539
Identification Number:	10.1111/j.1467-985X.2007.00536.x
Status:	Peer Reviewed
Publication Status:	Published
Access rights to Published version:	Restricted or Subscription Access
Funder:	Engineering and Physical Sciences Research Council (EPSRC), Economic and Social Research Council (Great Britain) (ESRC)
Version or Related Resource:	Discussion of this paper: Dorling, D., et al. (2008). Discussion on the paper by Curtice and Firth. Royal Statistical Society. Journal. Series A: Statistics in Society, 171(3), pp. 533-539. http://wrap.warwick.ac.uk/id/eprint/30069
Related URLs:	Related item in WRAP
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URI:	http://wrap.warwick.ac.uk/id/eprint/30068