Implications of a Multidimensional Model of Ideology for Political Psychology

Voting is a one-dimensional solution to a multidimensional problem. The modern democratic process implicitly assumes that the single data-point of an individual’s vote must indicate their preference on a plethora of policy issues, from marginal tax rates to the contents of the curriculum; the fixing of potholes in one’s neighbourhood to the nation’s diplomatic approach in conflicts on the opposite side of the world. Through the concept of the mandate, elections are widely assumed to legitimise their winner’s policy proposals by measuring the public will, but it is obvious that they cannot completely do so. Yet this is exactly how we build and conceive of our modern democracies, believing that electoral representation will “refine and enlarge the public views” (Madison, 1787). Theorists of democracy identify ideology, and ideological parties, as the (partial) solution (Downs, 1957). By packaging together sets of beliefs under some greater organising principle, we can interpret one vote as an endorsement of a party or politician, who in turn endorses an ideology, which in turn instructs them on how to handle political issues. The central motivation of this thesis is an attempt to quantify and identify the structure of ideology, by reducing the noise behind an individual’s vote into multiple ideological “dimensions” - broad categories of belief which encompass many attitudes at once, but which are sufficiently numerous to represent the breadth of issues addressed by ideologies. I attempt to establish the number and nature of these dimensions, and the implications of a multidimensional theory of political preference. Such multidimensional models of ideology are not new to political science, but their application to the field of political psychology has been inconsistent (Feldman & Johnston, 2014). This thesis attempts to address this inconsistency. In Chapters 1 and 2, I review existing multidimensional models, and advance a theoretical explanation of their nature, methodology, and utility. Subsequently, chapters take a largely 6 data-driven approach to define the shape and content of these models. Chapter 3 reports the central role of a multidimensional model in a novel computational measure of issue polarisation. Existing approaches conflate extremism with polarisation, or do not allow for comparative research, but a multidimensional approach can address these shortcomings. In Chapter 4, I turn to the individual level, testing whether dimensions differ in their heritability and reliability. Chapter 5 builds on the influential work of Malka et al. (2019), who demonstrate international differences in the alignment of ideological dimensions. I extend this approach sub-nationally within the UK, demonstrating that such variance is a powerful driver of electoral behaviour. Finally, in Chapter 6, I present a novel “electoral convergence effect”, which applies a multidimensional model to theories of “enlightened preferences” (Andersen et al., 2005). The body of work converges to the conclusion that multidimensional spatial models continue to have great explanatory and theoretical power in politics, and I advocate for their increased adoption in political psychology.

Name dc:type.qualificationname

Doctor of Philosophy (PhD)

Level dc:type.qualificationlevel

Doctoral

Grantor dc:publisher.institution

University of Cambridge

Year dc:date.issued

2025

Author dc:creator

• Ackland, James

Advisor dc:contributor.advisor

• De-Wit, Lee

• Election
• Electoral Science
• Ideology
• Political Psychology
• Spatial Model of Ideology

Licence

• https://www.repository.cam.ac.uk/bitstreams/843611a2-814f-4de8-bd63-4ce74d1ee897/download
• https://creativecommons.org/licenses/by/4.0/

Language dc:language

eng

DOI dc:identifier.doi

https://doi.org/10.17863/CAM.122572

OAI identifier oai:identifier

oai:www.repository.cam.ac.uk:1810/391435