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Experiment 1

[...] We therefore attracted participants' attention to either the outgroup as a whole or to different sub-groups within the out-group, and then, several weeks later, measured participants' perceived variability and attitudes towards that out-group. [...]

Participants A total of sixty-four first-year psychology students from the Clermont University, France took part in the experiment. [...] Approximately 70% of the participants were women.

Stimulus material

Participants read one of two texts that were ostensibly excerpts of a travel journal of a person traveling in Morocco. The participants' task was to underline the spelling errors in the text. [...] In the “homogeneous condition,” the author described the particularities of the Moroccans referring to them always as a single group [...]. In the “heterogeneous condition,” the author described his experience in Morocco mentioning several different sub-groups, such as farmers, working-women and elder citizens. [...]

Procedure Students were recruited in four methodology classes with 14 to 16 students each to participate in a “psycholinguistic experiment.” They were tested in their classroom, and each of the four classes was randomly assigned to one of the two experimental conditions. Students had been randomly assigned to classes at the beginning of the semester. In each session, students first participated in a short experiment and then spent the remainder of the session discussing methodological and experimental design issues related to this experiment. The ostensible psycholinguistics study consisted of reading the travel journal and circling the spelling errors (the experimental manipulation). The following week, the instructor asked them to participate in another short study that was unrelated to the present research. Two weeks after having read the travel journal, students completed the questionnaire with the perceived variability measure and the Modern Racism Scale. [...]

Experiment 2

Experiment 2 was designed to extend the findings of the previous experiment. We wondered whether more positive attitudes toward the out-group that resulted from the increase in perceived variability translate into less discriminatory behaviors when participants interact with real members of the target group. Also, we decided to use an even more elaborate cover story to make sure that participants' reactions were not driven by social desirability concerns. [...]

Participants One hundred and fourteen female undergraduate students at the Clermont University, France, participated in the experiment [...]. Thus, we report data from 36 groups of 3 participants each (N= 108). These groups were randomly assigned to one of the two experimental conditions.

Procedure and stimulus material Three female participants who did not know each other prior to the experiment were asked to come to the laboratory at the same time. They sat in a waiting area in which a female student of Chinese nationality, a confederate of the experimenter, was already waiting. When all three participants had arrived, a male experimenter, who was Caucasian (French), entered the waiting area and asked the three participants and the Chinese confederate for their names. He mentioned that two students were still missing, and asked the Chinese confederate if she knew them, reading out loud two fictitious Chinese names on his sign-up sheet. The confederate said no. The experimenter addressed himself to the three French participants and told them that he would get them settled in the laboratory [...]. He left the room and came back one minute later saying that the remaining two participants and the other experimenter had arrived [...]. The experimenter explained that he was interested in how individuals in big companies collaborate [...]. [...] The experimenter asked participants to imagine themselves in the position of an employee of a large multi-national company during the entire study. In order to make things easier, he told the participants, he would refer to them as the “French group” and to the group in the other room as the “Chinese group.” The experimenter then explained that the members of the two groups would get to know each other. He gave each of the participants a copy of the self-disclosure questionnaire and asked them to fill it out. The questionnaire contained 10 questions about participants' attitudes and behaviors at the workplace. [...] The experimenter made clear that the participants' responses would be given to the Chinese group and that they would get a chance to see the responses of the Chinese group. The similarity of the answers among the three members of the Chinese group constituted our experimental manipulation. In the “homogeneous condition,” the three individuals' answers were relatively similar to each other on all of the 10 items [...]. In the “heterogeneous condition,” the three responses were relatively dissimilar from each other [...]. [...] Participants then completed the Lost-on-the-Moon task [...]. In this task, participants are asked to imagine that their group is lost on the light side of the moon and that they want to get back to their space shuttle that is about 300 km away. The group has ten objects, and the group members' task is to rank these objects in the order of their utility. After two minutes of discussion, the experimenter asked the participants to fill out the individual response sheet silently, without talking to their fellow group members. The variability of the rankings of the Chinese group constituted the reinforcement of the manipulation of perceived variability. In the “homogeneous condition,” the same object was given more or less the same rank by all three group members [...], and in the “heterogeneous condition,” the rankings were quite different [...]. The rankings on the group response sheet were again in three different colors, one for each member of the Chinese group. Participants next completed the “range task” used in Experiment 1. They evaluated the members of the Chinese group on the traits “egoistic,” “hard working,” “aggressive,” “cheerful,” “competent,” “threatening,” “unpleasant,” and “trustworthy”. The range task was followed by a question asking about participants' general impression of variability [...], and five other questions about impressions of and attitudes toward the out-group [...]. [...] To measure discrimination, participants were asked to imagine that their group and the “Chinese group” were lost on the moon at the same place. There were enough of the useful objects to be divided generously between the two groups.1 There were, however, few instances of the six least useful objects, so these could not as easily be shared. The participants were asked to imagine that the groups had drawn straws, that their group had won, and that they, therefore, had the right to decide which group received each of the objects. Participants were told that they were entirely free in their decision: they could give all six objects to their own group, all six objects to the out-group, or any intermediate solution. Participants completed this task individually. For the second measure of discrimination, participants were asked to imagine that they were in the position to distribute a 100€ monetary reward among their own group and the Chinese out-group. [...]

Experiment 3

[...] Are the beneficial effects of perceived variability robust enough to affect the ways in which people interact with members of out-groups? [...]

Participants A total of forty-eight female undergraduate students at the Clermont University participated in the experiment [...]. Accordingly, the data from 43 participants were analyzed.

Stimulus material In order to manipulate the perceived variability of Arabs, we used two different posters that were 40 by 60 cm large and printed on glossy paper. In the heterogeneous condition, the poster contained photographs of 12 male and female Arab individuals of different ages, hairstyle and clothing. Next to two thirds of the photographs, there was a small box with the person's first name, his or her age, and a characteristic describing the person [...]. Below the photographs, there was a slogan, printed in large letters: [Text Stimulus A]. In the control condition, we used a poster with a similar layout that encouraged people to eat more fruits and vegetables. Perceived variability of French and Arabs was assessed the same way as in Experiment 1 [...].

Procedure [...] The experimenter explained that he had to prepare the experimental material and asked them to take a place in the waiting room. There were six posters in the room, and the sixth poster either displayed the 12 Arab individuals (heterogeneous condition) or promoted the consumption of fruit (control condition). [...] Participants completed a filler task for fifteen minutes. When they finished, participants were asked to complete the measures of perceived variability, which were presented as a pretest for another colleague. [...] He told them that they had to go to an office in another building in order to get their experimental credit validated. He gave them a map, printed on bright green paper so that the confederate could recognize them. In the other building, a female confederate of Arab appearance walked in front of the participants and dropped a big plastic bag so that its contents spilled on the ground. The dependent variable was whether the participant offered her help in the first 20 seconds. [...]

Experiment 4

The primary goal of the next experiment was to extend the analysis of perceived variability to discrimination in other real life situations. [...]

Participants One hundred and twenty-nine students participated in the experiment in partial fulfillment of course credit. They were randomly assigned to one of six experimental conditions that crossed “experimental condition” (heterogeneity vs. control vs. homogeneity) and “target CV” (French vs. Arab).

Material In the first phase, participants in the heterogeneity and homogeneity conditions were asked to look at and to memorize the pictures of eight individuals. The pictures were head and shoulder photographs of Arab individuals who differed in gender, age and formality of clothing. [...] Participants in the heterogeneity condition were instructed: [Verbal Stimulus A]. Participants wrote the sentences on an answer sheet. After the pictures with the Arab individuals, participants formed sentences about differences (heterogeneity condition) or similarities (homogeneity condition) among eight abstract paintings. This second task was added to augment the credibility of the cover story. Participants in the control condition did not complete the sentence task. Afterward, participants in all conditions completed five questions about their general impressions of variability [...]. [...] In the second phase of the experiment, participants evaluated four job candidates. They first received a description of the job to be filled, a sales representative. The one-page description contained a list of tasks that the person would do on a daily basis as well as a description of the ideal candidate's profile. Participants then saw the CVs of four candidates. [...] One of the CVs, the so-called “target CV,” was clearly better than the other three CVs, two were of intermediate quality, and one was relatively poor. [...] The ethnicity of the candidate with the target CV was experimentally manipulated: For half of the participants, the candidate had a male French name (François Durand), for the other half a male Arab name (Karim Benlabssir). All other three candidates had French names. One of the CVs of intermediate quality was from a female candidate, the other three from male candidates. After having examined the CVs participants filled out a questionnaire in which they first evaluated each candidate on two dimensions [...]. Participants gave their responses on continuous rating scales that were later transformed in 28 intervals of equal size. Participants then rank ordered the four candidates from the most qualified to the least qualified. Finally, they selected the two candidates they would invite for a job interview. In the third phase of the experiment, participants in the heterogeneity and in the homogeneity conditions saw 16 Arab individuals [...] and were asked to decide for each one whether they had seen him or her in phase 1. [...]

Procedure Upon arrival at the laboratory, participants were told that they would be participating in two unrelated experiments. The first experiment was on memory, the second on judgment processes in hiring situations. Participants first saw the 8 Arab individuals and were asked to form sentences, and then did the same thing with the 8 abstract paintings. They were told that their memory for these individuals and paintings would be tested later. All participants then answered the five questions about their general impressions of variability of Arabs. In a different experimental room with the “next experimenter,” participants evaluated the four CVs. Back in the first experimental room, they completed the recognition task. [...]