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Experiment 1

[...] Experiment 1 [...] examining the effects of ingroup or outgroup categorization compared with a neutral source categorization condition in the same paradigm, while also testing the extent to which the effects of the source of categorization on intergroup orientations are mediated by differences in which participants personally endorse a one-group representation of the groups. In this experiment, high school students read a newspaper article about the opinions of citizens of the European Union (EU) that included information that members of (a) the participants’ national ingroup [...], (b) an outgroup [...], or (c) a neutral group of professionals [...] We measured the extent to which participants perceived the groups within a common ingroup identity (a onegroup representation) and their positive intergroup orientations toward the immigrant group. [...]

Participants and Design. Fifty-five high school students (28 male, 27 female, M _age = 14.83, SD = 0.71) from Madrid, Spain, participated in the present study in their classrooms with the consent of their parents. Participants were randomly assigned to one of the three experimental categorization source conditions (ingroup source vs. outgroup source vs. neutral source).

Procedure. [...] Participants were then asked, ostensibly to acquaint them with the issues, to read a newspaper article, [Text Stimulus 1...] Information presented within the article was systematically varied to represent the three experimental conditions. In the ingroup condition, the article reported that, [Text Stimulus 2...] In the outgroup condition, [Text Stimulus 3...] In the neutral condition, participants read about a group of professionals not specifying the experts’ particular nationalities, discussing the EU and immigration in Spain. The article reported that [Text Stimulus 4...] After reading the newspaper article, participants were asked to respond to a series of questions about their attitudes and orientations. Participants responded to all items on scales ranging from 0 (totally disagree) to 6 (totally agree). [...] Some of these items were designed to test whether the experimental manipulation was successful and to assess possible unintended influences in the study, specifically differences across conditions in perceptions of the strength of endorsement for common identity, credibility of the article, and relative status of the ingroup and outgroup. Perceptions of the strength of endorsement for common identity in the article was assessed with the item: [Text Stimulus 5...] Six items assessed the perceived credibility of the article [...] To examine how participants perceived the status of immigrants, we asked them to what extent they agreed with the following statements: [Text Stimulus 6...] Next, we assessed one potential mediating variable. Participants’ personal representations of common group identity between Spaniards and Eastern European immigrants was assessed [...] by asking Spanish participants to rate the extent to which they felt that Eastern European immigrants in Spain and Spaniards were “one group.” [...]

Experiment 2

Experiment 2 used the same basic design and procedures used in Experiment 1, with two main changes. First, besides one-group representations, we also assessed symbolic threat as a potential mediator of the effect of the ingroup/outgroup categorization manipulation. Second, because we were interested in the dynamic relationships among one-group representations, threat, and intergroup orientations, we compared the ingroup categorization condition to the outgroup categorization condition, for which Experiment 1 implicated the role of threat; there was no neutral source categorization condition in this study. [...] Thus, the empirical focus in Experiment 2 was on symbolic threat. [...]

Participants. Seventy high school students (34 boys, 36 girls, M _age = 14.48, SD = 1.83) from Madrid, Spain, participated in the present study in their classrooms with the consent of their school and parents.

Procedure. The design and procedure of Experiment 2 were very similar to those of Experiment 1. With respect to the design, however, there were only two conditions for the source of categorization: Participants were randomly assigned to either an ingroup source or an outgroup source condition. In Experiment 2, which was also described as a survey of Spaniards’ opinions about immigrants from Eastern European countries that belong to the EU, participants read the newspaper article that was used in Experiment 1. [...] After reading the newspaper article, participants were asked to respond on scales ranging from 0 (totally disagree) to 6 (totally agree) to a series of questions about their attitudes and orientations as they did in Experiment 1. Among questions asking students’ opinions about the newspaper article and general educational issues, we included the same measures as those in Experiment 1: perceptions of the strength of endorsement for common identity, credibility of the article (α = .73), and disagreement with statements that the outgroup was higher in status than the ingroup (r = .85, p < .001). Next, we assessed two potential mediating variables: personal representations of common group identity (with the same item we used in Experiment 1), and then symbolic threat. Symbolic threat was measured by responses to a three-item scale [...] Intergroup orientations were measured with the same 10-item scale used in Experiment 1 (α = .96).