1. Internet Experiments in the 2005 BES David Sanders Harold Clarke Marianne Stewart Paul Whiteley

2. Preferences and Party Choice Two traditions: Downs and spatial modellers: Preferences are exogenous Campbell and the social psychologists: Preferences are endogenous, determined by a variety of contextual and conditioning factors

3. Preferences are Exogenous Voters maximise utility by selecting the party that is closest to them in a left-right ideological space. Voter i’s utility for party k is given by U i (k) = – (x i – s k ) 2 where x i is i’s preferred ideological position and s k is i’s estimate of the position of party k. Note here that x i is assumed to be time invariant.

4. Preferences are Endogenous What happens if measures of ideological position cannot be anchored in what voters say at time t because their self locations are not exogenous? Suppose that x i are affected by the campaign messages to which they are exposed: x it =  0 +  1 x it-1 +   z kt where  k is a vector of effect parameters and z kt is a vector of campaign variables. Formal theory implications: How do we obtain an equilibrium in this situation? Can only do so if we make further assumptions about z kt Empirical implications: we need to know what t is and what the relationship is between x it and z kt

5. How can this question be addressed? Experimental work an obvious approach: do voters shift their ‘ideological positions’ if they are given new information analogous to the information they receive during campaigns? Considerable advantages in conducting experiments on representative national samples; much more likely to produce ‘generalisable’ conclusions. One way of assessing whether preferences differ at two points in time is to give feedback to respondents about their ‘initial’ ideological positions. In conjunction with these ‘initial positions’ – the x it-1 in our previous slides – we can also give ‘campaign information’ the z kt in our previous slides – for example about ‘the positions of the parties’ The internet represents an ideal vehicle for providing feedback about the x i and for manipulating the z kt

6. Procedure: the Internet Survey Experiments Ask respondent to self-locate on two 0-10 scales: tax/spend and liberal/authoritarian Later in survey show respondent where s/he is located in 2-d space defined by earlier responses Ask if respondent wishes to re-locate self Split sample on cues provided (eight experimental groups plus control – see next slide) Explore differences in patterns of response in control and test groups

7. What are the z kt ? Two general sets of z kt : Parties Leaders …and combinations Experiments: 1: Control: just feed back x it-1 for Respondent (R) 2: R + ‘average voter’ 3: R + ‘party supporters’ for Lab, Con LD 4: R + named leaders (Blair, Howard, Kennedy) 5: R + leader + party label 6: R + parties 1983 scenario 7: R + parties 1964 scenario 8: R + parties 2005 scenario 9: R + leaders + supporters (5)

9. 1: Control4: R + leaders7: R + parties 1964 scenario 2: R + average voter5: R + leader + party label8: R + parties 2005 scenario 3: R + party supporters6: R + parties 1983 scenario9: R + leaders + supporters (5) Note the difference between the control and all test groups

10. 1: Control4: R + leaders7: R + parties 1964 scenario 2: R + average voter5: R + leader + party label8: R + parties 2005 scenario 3: R + party supporters6: R + parties 1983 scenario9: R + leaders + supporters (5) Differences between control and each test group almost all statistically significant

11. 1: Control4: R + leaders7: R + parties 1964 scenario 2: R + average voter5: R + leader + party label8: R + parties 2005 scenario 3: R + party supporters6: R + parties 1983 scenario9: R + leaders + supporters (5) Differences between control and each test group almost all statistically significant

12. With multivariate controls, it is the party-based effects than continue to be statistically significant; respondents change their tax-spend ideological positions in response primarily to party cues. Same result with crime-rights scale and with Euclidean distance model based on the two scales in a 2-d space. Modelling absolute changes in self-locations

13. Modelling directional changes in self-locations Same pattern of effects observed with separate models of cues relative to R’s Personal Pre-experimental positioning of self and of the parties. Conclusion: positive coefficients indicate that PARTY CUES ATTRACT

14. Spatial model of voter utility assumes that voters’ ideological/policy preferences are fixed. When people are invited to adjust their recently made self- placements on two ideological scales, a non-trivial proportion of them elects to do so. Voters’ x it-1 values differ from their x it values even within the space of a few minutes. The type of positional cues to which people are exposed – the z ij – affects the extent to which they wish to adjust their self- placements. Information about the positions of named party leaders seems to have little effect on ‘adjustment’. Information about ‘parties’, ‘party supporters’ or ‘leaders with party labels’ does affect the extent to which people wish to ‘adjust’. Conclusions

15. Analyses of respondents’ directional movement suggests that voters are attracted to party cues (of whatever sort), rather than repelled by them. Party cues help to persuade people to shift their ideological/policy positions. The internet allows relatively sophisticated survey experiments to be conducted with representative samples of the electorate, rather than with small and unrepresentative groups of (e.g.) undergraduate students. Future experiments: need to simplify the stimuli, e.g. single or two-party stimuli; allowing respondents to vary parties’ positions as well as their own. Conclusions….

17. Party-based comparisons with control tend to give higher eta values than leader-based equivalents

18. Again, party-based comparisons with control tend to give higher eta values than leader-based equivalents