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Experiment 1

Method 

Subjects and Design. Forty-nine undergraduates participated in the experiment in return for payment. The experiment had a 3 (presentation mode: forced/free — no time pressure/free — high time pressure) x 3 (trait topics: stereotypic/counter-stereotypic/stereotype-neutral) x 2 (questions: stereotype-matching/stereotype-mismatching) design with the first factor a between-subjects factor and the second and third factors within-subjects factors. 

Stimulus Materials 

A series of pilot studies were conducted to identify a suitable target group and its stereotype. In the first pilot study 10 students were asked to list any groups in society which were easy to distinguish and which they could characterize by a few key features. One frequently identified group was doctors. In the second pilot study 20 students rated doctors on 50 personality traits, including those mentioned by subjects in the first pilot study [...]. From these ratings stereotypic (mean ratings within the top 10 ratings and no more than two subjects rating the trait in the opposite direction from the scale midpoint to the mean), counter stereotypic (mean ratings among the lowest 10 ratings and no more than two subjects rating the trait in the opposite  direction from the scale midpoint to the mean) and stereotype-neutral (mean ratings within two points of the scale midpoint and no more than two subjects rating the trait more than two points from the scale midpoint) traits were identified. Four of each type of trait were chosen for use in the experiment proper [...]. [...] An analysis of variance (ANOVA) on the trait ratings revealed a significant effect of trait type, F(2,119) = 44.63, p < 0.0001. [...] An additional 10 students rated the target group as a whole on the 12 selected traits to provide baseline data against which the experimental subjects could be compared for evidence of actual stereotype change [...]. For each of these 12 traits two questions were to be used in the experiment proper, one matching (a ‘yes’ answer confirming the stereotype of the group and a ‘no’ answer disconfirming the stereotype) and one mismatching (a ‘no’ answer disconfirming the stereotype) and one mismatching (a ‘no’ answer confirming the stereotype of the group and a ‘yes’ answer disconfirming the stereotype). In order to select appropriate questions 20 subjects rated each of a pool of 48 questions, constructed by the experimenter and assistants. First, they rated how useful, or diagnostic, the answer to the question would be in terms of the given trait. [...] Subjects were told to give a higher rating the more the question would distinguish between those with a high and a low level of the trait. [...] Second, subjects estimated the percentage of doctors who would respond ‘yes’ to each question. For each trait the two questions chosen for use in the experiment proper were matched on their diagnosticity or usefulness ratings (Ms = 6.46,6.60 and 6.08 for the stereotypic, counter-stereotypic and neutral traits respectively) but one was a stereotype-matching (mean % ‘yes’=72 per cent) and one a stereotype mismatching question (mean % ‘yes’=33 per cent). Sentence pairs were also matched for word length. 

Across the total question set, three-quarters of the stereotype-relevant questions [...] were answered in a stereotype-consistent manner [...]. Across the entire question set, then, 0.167 of answers were stereotype-inconsistent. The stereotype-inconsistent answers were evenly distributed across target group members [...], trait topic [...] and question type [...]. [...] The time allowance for subjects in the high time pressure was set at one third of the time it took five pilot subjects to complete the task (M=7.5 minutes). In this condition a clock counting down from 2.5 minutes was visible on the screen so that subjects were aware of how much time they had left. 

Procedure 

All subjects were informed that they were participating in an experiment on social perception, concerned with how different groups in society [...] are seen by others. They were randomly allocated to one of the three presentation mode conditions [...]. [...] The first computer screen informed subjects that they would be asked for their perceptions of one particular group, doctors. Before giving their own perceptions of the group they were to be given examples of the behaviour of some members of the target group, which had previously been collected in a series of interviews of doctors conducted by the experimenter. Subjects were told that [...] they would receive information about just four of the doctors interviewed. These four had been chosen as representatives of doctors in general. Each of the doctors answered questions [...] on three different topics. These topic areas were the trait topics identified in the pilot studies. Subjects were instructed to use this information to help them in cementing their perceptions of the target group as a whole. Subjects in the forced condition were instructed to work their way through all the presented information. Subjects in the free condition were instructed to only read as much of the information as they felt they needed in order to be confident in their perceptions of the group as a whole. These subjects were free to terminate the information gathering at any stage. When subjects had read the instructions they clicked on a 'run' button to proceed with the experiment. At this point the experimenter left the room until the subjects had completed the experiment. The first experimental screen displayed the names of the four doctors. To receive information about any of the doctors subjects had to click on their name. A new screen appeared with the three topics describing that doctor. Across the four doctors these topics were close synonyms of the 12 traits identified in the pilot studies. For each target there was one stereotypic, one counter-stereotypic and one neutral trait topic. To receive information about any of these topics the subject clicked on the topic name. A screen with the two questions related to the topic, one stereotype matching and one stereotype-mismatching, then appeared. To see the doctor's answer to one of the questions, subjects clicked on a box labelled ‘answer’ next to each question. A new screen with either ‘yes’ or ‘no’ on it appeared. Subjects then clicked on an ‘OK’ button to return to the first experimental screen, containing the doctors’ names. After a question had been selected it was removed from the screen. [...]

Subjects in the forced presentation condition were required to continue their information search until all the questions and answers had been selected, and therefore disappeared from the screen. The trait rating dependent measure then automatically appeared. The trait rating task asked subjects to rate how characteristic a number of personality traits were of doctors as a whole [...].. [...] In the free presentation condition subjects could stop the information search at any time by clicking on a ‘finished’ button on the first experimental screen. The trait rating task appeared either when the ‘finished’ button was selected or when all the questions had been asked. [...]

Experiment 2

Method 

Subjects and Design. Fifty-nine undergraduates participated in return for payment. The experiment has a 2 (presentation mode: forced/free) x 3 (trait topic: stereotypic/counter-stereotypic/ stereotype-neutral) design, the first factor being a between-subjects and the second factor a within-subjects factor. 

Stimulus materials 

The target group for this experiment had to be one for which there was an easily identifiable negative stereotype and for which characteristic behaviours could be identified. People with schizophrenia were selected as a group which met these two criteria. The key features of the schizophrenic stereotype were taken from Neuberg and Fiske (1987). Ten control subjects rated the target group on 20 personality characteristics, including those identified in Neuberg and Fiske (1987) [...]. From these ratings stereotypic, counter-stereotypic and stereotype-neutral traits were identified [...]. Four of each type of trait were chosen for use in the experiment proper [...]. [...] An additional 10 subjects then rated the target group on the 12 selected traits [...] in order to provide baseline data against which the ratings of the experimental subjects could be compared for evidence of actual stereotype change. For each of the trait topics [...] a number of behaviours were generated by the experimenter and assistants. Ten subjects rated how good an example of the trait the behaviours were [...] and how high a level of that trait the behaviour demonstrated [...]. Ten subjects rated how useful the behaviour would be in determining the level of the given trait possessed by the person answering. Subjects were told to give a higher rating when the question would more strongly distinguish between those with high and low levels of the trait [...]. Subjects were then asked for feedback about their ratings and how behaviours could be changed in order to increase the ratings. After these changes were made additional groups of eight subjects rated the behaviours as above. For each of the 12 experimental traits a behaviour which was considered both a good example of the trait [...] and was considered useful [...] was identified and used in the experiment proper. [...] For each of the trait topics two of the traits were described by consistent behaviours [...] and two by inconsistent behaviours [...].

For the stereotype-relevant traits [...] half of the information was stereotype-consistent [...] and half stereotype-inconsistent [...]. Across the set of behaviours one-third of the information was stereotype consistent, one-third was stereotype inconsistent and one-third was stereotype neutral. The stereotype-inconsistent answers were evenly distributed across target group members [...] and trait topic [...].

Procedure. The procedure was similar to that followed in Experiment 1. The major difference was that rather than two questions for each trait there was only one statement. 

Experiment 3

Method 

Subjects and Design. Fifty-two psychology undergraduates participated in the experiment in return for course credit. The experiment had a 3 (processing goal: accuracy/justification ~ positive group/justification -negative group) x 3 (trait topics: stereotypic/counterstereotypic/stereotype-neutral) x 2 (questions: stereotype-matching/stereotype mismatching) mixed model design, the first factor being a between-subjects factor and the second and third factors within-subjects factors. 

Stimulus materials 

The same stimulus materials as for Experiment 1 were used. In addition [...] subjects also received one of three processing goal instruction sets prior to starting the computer task. In the accuracy condition, subjects were instructed to try to be as accurate in their perceptions as possible. [...] In the two justification conditions subjects were told that after they had given their perceptions of the target group they would be asked to justify those perceptions. [...] For the justification, positive group condition subjects were told that their justifications were to be used by a doctors’ support group. For the justification, negative group condition subjects were told that their justifications were to be used by a patient pressure group. [...]

Procedure 

Subjects were randomly allocated to one of the three experimental conditions and tested individually. On entering the laboratory subjects were told that they were participating in a social perception experiment concerned with how different social groups are seen by others. They were told that the study they were taking part in was concerned with perceptions of doctors. Subjects were then given the processing goal instructions for their experimental condition. The procedure was then the same as the free presentation, no time pressure mode of Experiment 1. Subjects in the justification conditions were not actually required to justify their opinions but were debriefed with regard to the purpose of this deception.