We developed the SIRD model to provide a more comprehensive account of the way relative deprivation and social identity combine to influence collective and personal responses to disadvantage. No previous studies have provided a complete analysis involving all these variables, but, as noted in the introduction, the model integrates other research that provides convergent evidence for the separate paths in the model. The SIRD model is the first to set out explicitly the mediating role of a social change belief structure in the context of personal and collective deprivation, as proposed by social identity theory.
In line with Tajfel and Turner's (1979) presentation of social identity theory, we find that among members of a disadvantaged group, the route from identifying with that group to developing intentions to change the status quo (in this case, voting for a separatist political party) is mediated by social change beliefs (Hypothesis 1). The SIRD model is also novel in specifying that social change beliefs should (and do in this case) mediate between aff CRD and voting intention (Hypothesis 2).This mediated path has not been tested to date because most studies examine either the relationship between aff CRD and militant attitudes, or the relationship between aff CRD and protest intentions or behaviours (Smith & Ortiz, 2002; van Zomeren, Postmes, & Spears, 2008). Most importantly, the model proposes that both aff CRD and social identification become articulated through social change beliefs, which mediate the impact of both variables on specific intentions to change the status quo. By showing that, with social change beliefs in the model, there are no direct paths from either identification or aff CRD to voting intention we strongly confirm the theoretical framework derived from social identity theory.
Distinctive consequences of CRD and ERD
Guimond and Dubé-Simard (1983) highlighted the conceptual and measurement distinction between ERD and CRD but did not fully test their distinctive effects, a gap that remains unfilled, particularly within the same sample and context (Smith & Ortiz, 2002). The SIRD model specifies that, because they relate to different levels of identity, there will be separate and different consequences of ERD and CRD (Hypothesis 3). This hypothesis was clearly supported. Smith and Ortiz's (2002) meta-analysis showed a strong effect of negative interpersonal social comparison on self-esteem, stress, and depression. Consistent with this, we found that ERD, which is based on interpersonal or intragroup comparisons, strongly predicted feelings of depression. In contrast, aff CRD, which is based on intergroup comparisons, predicted Scottish nationalist social change beliefs, which in turn, predicted SNP voting intentions. This reinforces other evidence that aff CRD is the proximal cause of militant attitudes and engagement in protest action and that aff CRD fully mediates the more distal effects of cog CRD (Dube-Simard &Guimond, 1986; Grant, 2008; Grant & Brown, 1995; Kawakami & Dion, 1995; Pettigrew, 2002).
More recently, intergroup emotions theory has emphasized the role of intergroup emotions in collective action and highlights that group and personal emotions have different antecedents and consequences (Smith, Seger, & Mackie, 2007).The present work is compatible with IET because the inclusion of aff RD, as well as the two outcomes – political intentions on the one hand and feelings of depression on the other – can be seen as relating to problem-focused and emotion-focused responses to the situation (see also van Zomeren, Spears, & Leach, 2008).
We also considered the specificity of the model. Might social identification or social change beliefs predict more general outcomes? Might general political engagement and activity be just as, or more, predictive of SNP voting intentions? The data showed clearly that a specific social identity, a specific intergroup comparison, and a specific social change belief structure were associated with a specific voting intention, irrespective of people's general engagement in politics. In contrast, general political engagement more strongly predicted general voting intentions and general political action intentions than did social change beliefs. These findings demonstrate the discriminant validity of our model. Identification with Scotland only motivated political actions that were specifically relevant to the improvement of the comparatively unfair conditions experienced by Scottish people as a whole.
Strengths, limitations, and future directions
Mummendey, Kessler, Klink, and Mielke (1999, p. 230) observed that, ‘studies of real groups in a particular social and historic context are especially rare’. Such studies give us a much better handle on the external validity of theory as well as opportunities to test proposed causal pathways to see if they fit the data. Indeed, the small amount of previous research that studied both national identity and relative deprivation (e.g., Kessler & Mummendey, 2002; Mummendey et al., 1999) has not included measures of political intentions and was conducted post-event (German re-unification). We tested the model using two representative cohorts of young people from a single political constituency and who were approaching their first opportunity to vote for a political representative. Our sample captured the full range of variance in the population of potential activists, rather than the more restricted ranges that might be observed in self-selected samples of activitists, or samples of psychology students participating in studies for course credit. Moreover, the identity and issues in question had longstanding social significance rather than being transitory or having been fabricated for the purposes of the study. Thus, the external and ecological validity of the study are extremely high compared to many others in the field (see van Zomeren, Postmes, & Spears, 2008). Moreover, as our respondents had not yet had an opportunity to vote, it was possible for us to be sure that their intentions were not simply self-reports of prior action or habit and that prior measures in the model were not simply post hoc justifications (cf. Manstead, Proffitt, & Smart, 1983).
We acknowledge limitations in the present data. In common with many multidisciplinary large-scale surveys, even though each survey item was subjected to extensive pilot work and scrutiny, the research required the use of a single or a small number of items to measure each construct. Unusually, however, in the present case the items were designed specifically to test social identity and relative deprivation theories, and the relevant items were drawn from previously established measures in the research literature, enabling us to test the model quite comprehensively. Overall, we feel that the clear support for the theoretical model shown in Figure 1, and the absence of non-predicted relationships among variables, suggests that the measurement quality was high.
Nonetheless, two specific measurement issues deserve mention. First, we are conscious that the measure of ERD, which refers to ‘satisfaction’, has semantic overlap with the depression measures even if the referent is different. Ideally, future research will employ multiple item measures for relative deprivation and, if relevant, will focus more precisely on the same domains (e.g., income) for each type of measure. Second, the reliability of the Scottish identity measure is poor. We suspect that this is because two of the three items are skewed as most respondents identify strongly with Scotland. We felt, therefore, that we were justified in using this scale and then repeating the analysis using the single ‘belonging’ item as a measure of identity because belonging is a key component of many multi-item identity scales (see Jackson & Smith, 1999). Note that the structural equation modelling results confirm the plausiblity of the measurement model for our identity measure as well as strong support for our theoretical model. That is the evidence suggests that our identity measure has validity because it relates to other variables in ways that were expected, a priori, according to theory.
Other aspects of the data merit some comment. The negative correlation between social identification and depression is consistent with the idea that a collective identity can buffer against other threats to the self-image (Major, Quinton, & McCoy, 2002). Importantly, however, this relationship is not substantially mediated by aff RD or social change beliefs, suggesting that it revolves around overall feelings of self-worth rather than the motivation to act on behalf of the collective. This is also consistent with the idea that being embedded in a strong collective identity and community can promote personal well-being (Abrams, 1992; Layard, 2005; Putnam, 2000).
Based on social identity theory and our own previous research, in which the path from identity to aff CRD was significant, whereas the reciprocal path was not (Grant, 2008), we assumed that identification should promote stronger aff CRD. However, the causal relationship could be reversed. The rejection identification model (Branscombe, Schmitt, & Harvey, 1999) would propose that respondents’ emotional reaction to disadvantage should strengthen their identification with Scotland. In fact, reversing the path between identification and aff RD did not change the model fit or reduce the strength of paths from either aff RD or identification to social change beliefs. Thus, the data are compatible with the idea that the causal relationship between identification and feelings of aff CRD are reciprocal as was suggested by van Zomeren, Postmes, and Spears (2008). Our current belief, therefore, is that the causal direction between these two variables may be tilted one way or the other by external contextual factors; these require investigation in future research. Moreover, the causal direction between identification and aff CRD does not undermine the doubly mediating role of social change beliefs for both variables proposed by the SIRD model.
A further limitation of the present research is that we did not have a measure of collective efficacy. Recently, this variable has been highlighted as contributing importantly to protest actions (e.g. Abrams & Randsley de Moura, 2002; Kelly & Breinlinger, 1996; van Zomeren, Postmes, & Spears, 2008). Moreover, just as we have highlighted distinct pathways for ERD and CRD, we would propose that personal efficacy should have distinct effects from collective efficacy, for example, the former having stronger effects on intentions to leave the group (a social mobility belief structure; Abrams et al., 1999). This perspective is generally compatible with the idea that social identities guide our political actions towards imagined futures, given situational constraints generated by existing political realities (Klein et al., 2007; Reicher & Hopkins, 2001). Therefore, a future development of the SIRD model will need to embrace the role of personal and collective efficacy.
Our model suggests that a strong social identity together with intense dissatisfaction arising from social injustices perpetrated against one's minority group is likely to spawn social change beliefs and intentions to take actions designed to right these injustices. Voting is probably the single most important and comprehensive means by which large proportions of a population are directly involved in political change. Our evidence emphasizes the value of a SIRD model to understand and predict intentions to vote for political separatist movements. Beyond voting, however, recent collective protests and other socio-political schisms, such as those in the Balkans, China/Tibet, former Soviet territories, and more recently Tunisia, Egypt, and Libya, suggest that a social change belief structure, especially once it becomes explicitly articulated and shared, may be necessary for people to channel their sense of identification with their group and frustration about its situation into coordinated political action. It remains for future research to test the generality of the SIRD model in different political contexts and with a wider range of intentions and outcomes, such as more costly or non-normative protest actions by members of a disadvantaged minority as they seek to achieve greater social equality.