Robyn M. Dawes

Behavior, communication, and assumptions about other people's behavior in a commons dilemma situation.

Abstract : Two experiments investigated effects of communication on behavior in an 8-person commons dilemma of group versus individual gain. Subjects made a single choice involving a substantial amount of money (possible outcomes ranging from nothing to

Factors influencing the use of a decision rule in a probabilistic task

10.50). In Experiment 1, 4 communication conditions were crossed with the possibility of losing money (loss, no loss). Subjects chose defecting or cooperating responses and predicted responses of other group members. Results showed defection significantly higher in no communication and irrelevant communication conditions than in relevant communication and relevant communication plus roll call conditions. Loss had no effect on decisions. Defectors expected much more defection than did cooperators. Experiment 2 replicated irrelevant communication and communication effects, and compared predictions of participants with those of observers.

Sex bias, diagnosis, and DSM-III

Abstract Two studies investigated conditions under which subjects would choose not to use a helpful decision rule that would have enabled them to choose correctly on a large proportion (70%) of judgment tasks. In Experiment 1 some subjects were warned that failure to use this rule would probably result in very poor performance. Other subjects were either told that 70% was as well as people can do or were encouraged to outperform the rule. This instructional variable was crossed with an incentive manipulation. Subjects were given either cash for each correct judgment, or a cash award for being the best judge in their group, or no monetary incentive. Those who were warned about abandoning the rule and those who were given no monetary incentive performed best. Those who were told that 70% was about as well as people can do judged as poorly as those encouraged to outperform the rule. Supplementary analyses indicated that both the warning and lack of incentive led subjects to judge more consistently, while subjects in the other conditions changed strategies more frequently after incorrect judgments. The results of Experiment 2 indicated that those who have expertise (or think they have expertise) tend to use a helpful decision rule less than do those with less expertise, and consequently do worse. We suggest that the factors which led subjects to shun the decision rule in these two experiments are present in many important decision-making situations.

Forecasting one's own preference

Sixty-five licensed clinical psychologists independently diagnosed 18 written case histories on the basis of 10 DSM-III categories. The results showed that females were rated significantly more histrionic than males exhibiting identical histrionic symptoms. There was no comparable sex bias to diagnose males showing antisocial pathology as more antisocial than females. The explanation proposed is that the antisocial category is behaviorally anchored whereas the histrionic category is trait dominated. Thus, the findings suggest that vague diagnostic descriptions promoted sex stereotyping and sex bias in diagnosis.

Stereotyping and Sampling Biases in Intergroup Perception

Abstract This paper compares two methods of making preference judgments based on multi-attribute inputs: (i) an intuitive global evaluation of each input in its totality, (ii) a separate evaluation of each input attribute weighted intuitively to form a linear composite. When judges in psychological, medical and business settings have been asked to make predictive judgments on the basis of multi-attribute input, method (ii) has proved to be superior — with unerring consistency. People are quite poor at making intuitive global judgments based on psychologically incomparable attributes and much poorer than they believe themselves to be. Nevertheless, for various illusiory reasons (e.g., biased feedback, overestimation of the predictability inherent in the situation), people prefer method (i). A preference judgment can be conceptualized as a predictive judgment of ones future ‘state of mind.’ Thus, the research findings strongly suggest that when making preference judgments method (ii) is superior, but will remain less popular than method (i).

Multivariate Selection of Students in a Racist Society: A Systematically Unfair Approach

In order for language to achieve its communicative function, it is essential that a given symbol be able to evoke a similar psychological representation across diverse individuals. Although many symbols or words succeed in eliciting highly similar meanings among different people, there is an important domain in which the discrepancies in meanings are at least as important as the similarities, and that is in the perception of the characteristics of human groups.

The robust beauty of improper linear models in decision making.

In American society, minority group members are underrepresented in academic settings—as undergraduates, as graduate students, and as faculty members. This underrepresentation has many pernicious effects. For example: (i) the subsequent earning power of minority group members is lower than that of majority group members, (ii) there is an underrepresentation of minority group members in important positions in society, (iii) there is an underrepresentation in high status occupations in general, and (iv) consequently, minority group children do not have as many high prestige models as do majority group children. Women are also underrepresented in academic settings.