On the Dual Process Model of Ideology and Prejudice: Identifying Causal Personality Effects and Revising Worldview Measures

Abstract

Despite the large body of research demonstrating good support for the Dual Process Model of ideology and prejudice (DPM; Duckitt, 2001), there is still a need for research examining whether these associations are truly causative and uni-directional as the model suggests. There is also a need to examine the mechanisms by which distal components of the model (personality traits and social worldview schemas) lead to the formation of more proximal ideological attitudes – indexed by the constructs Right-Wing Authoritarianism (RWA) and Social Dominance Orientation (SDO). Moreover, of the model components, social worldviews has garnered the least attention from researchers, and there are recent concerns about the construct validity of the DPM worldview measures that need to be addressed. This thesis presents a series of six manuscripts that address issues around (a) the causative effects of Big-Five personality traits on RWA and SDO, as well as the specific hypothesised mechanism of one particular trait, Openness to Experience. The thesis also addresses (b) the lack of a comprehensive understanding of the worldview component in the DPM and issues pertaining to the measurement and operation of the two worldview components – dangerous and competitive. These interrelated issues were examined using a variety of study designs including short-term longitudinal, meta-analytic, and experimental. The converging lines of evidence are presented in three sections. The evidence presented in Section 1 suggests that certain personality traits (Big-Five Agreeableness and Openness to Experience) causatively and unidirectionally predict individual differences in RWA and SDO using a national sample with structural equation modelling and longitudinal models. Section 2 confirms an asymmetry in effects sizes in the DPM (see Van Hiel, Cornelis & Roets, 2007) and demonstrates that this is likely due to item content overlap, particularly between measures of competitive social worldviews and SDO This section employed meta-analytic and factor analytic scale development techniques. Section 2 also presents a novel measure of social worldviews that addresses this content-overlap issue. Finally, and consistent with arguments made recently by Sibley and Duckitt (2012, 2013), my new measure of worldviews is utilised in Section 3 using novel experimental methods to show that Openness to Experience operates by biasing individuals low in this trait to be more attentive to and more influenced by normative information suggesting that the people “out there” in the social world are potentially dangerous and threatening. Taken together, these findings contribute to the current need for evidence demonstrating specific hypothesised causal associations in the DPM.