Structural cleavages, electoral competition and partisan divide: A Bayesian multinomial probit analysis of Chile’s 2005 election Ramon Michael Alvarez, Gabriel Katz * Division of Humanities and Social Sciences, California Institute of Technology,1200 E. California Blvd. MC 228-77, Pasadena, CA 91125, USA article info Article history: Received 13 December 2007 Received in revised form 9 May 2008 Accepted 8 August 2008 Keywords: Bayesian multinomial probit Chile Multi-candidate elections abstract The transformations in Chile’s party structure since 1989 have led several authors to examine the main cleavages shaping partisan divisions and the impact of different factors on citizens’ party preferences. Previous studies, however, failed to analyze the effect of these variables on actual vote choice and neglected the influence of election-specific factors. In order to address these issues, we implement a Bayesian multinomial probit model to analyze Chile’s 2005 election. We show that, while both socio-demographic variables and attitudes towards democracy affected voter behavior, the latter were the main determinants of the choice between Chile’s two main political coalitions. In addition, we find that the presence of a second conservative candidate, together with voters’ stra- tegic considerations, significantly affected candidate choice. These results cannot be accounted for by analyses focused on citizens’ party identification or by methodologies that ignore the effect of substitution patterns between candidates on voters’ electoral behavior. Ó 2008 Elsevier Ltd. All rights reserved. 1. Introduction Chile’s post-authoritarian party structure, dominated by two stable and solid multi-party coalitions, contrasts with the highly fragmented system existing prior to the 1973 military coup (Valenzuela and Scully, 1997; Tironi and Agu ¨ ero, 1999; Alema ´ n and Saiegh, 2007). Since the re- establishment of democracy, the center-left Concertacio ´n coalition, comprising the Socialist Party (PS), the Party for Democracy (PD), the Christian Democrats (CD) and the Radical Social-Democratic Party (PRSD), has been in control of the presidency and held the majority of the legislative seats. The other major coalition, the conservative Alianza por Chile, is made up of the Independent Democratic Union (UDI), the National Renewal Party (RN) and the Centrist Union (UCC). Although other minor parties exist outside these blocks, these two coalitions have dominated contemporary politics in Chile. There has been considerable debate among scholars about the reshaping of the Chilean political system and about the relative influence of different factors on voters’ behavior in this new setting (Valenzuela and Scully, 1997; Tironi and Agu ¨ero, 1999; Torcal and Mainwaring, 2003). Some authors argue that the social and cultural cleavages (in particular, class and religious divisions) that originally structured the Chilean political system still play a predom- inant role in defining political identities, and that the division between supporters and opponents of the authoritarian regime that marked the democratic transi- tion was the result of a particular historical background and is likely to fade as democracy is consolidated (Scully, 1995; Valenzuela, 1995; Bonilla, 2002). Other researchers, however, maintain that the new authoritarian–democratic cleavage has come to dominate party competition, inte- grating and reorganizing traditional sources of partisan divisions and reflecting intense discrepancies about regime preferences and conceptions of democracy in the Chilean * Corresponding author. Tel.: þ1 626 395 4371; fax: þ1 626 405 9841. E-mail address: gabriel@hss.caltech.edu (G. Katz). Contents lists available at ScienceDirect Electoral Studies journal homepage: www.elsevier.com/locate/electstud 0261-3794/$ – see front matter Ó 2008 Elsevier Ltd. All rights reserved. doi:10.1016/j.electstud.2008.08.001 Electoral Studies 28 (2009) 177–189