Context effects in the measurement of optimism in probability judgment

Examined the role of contextual information such as comparison standard on self-other probability judgments regarding the occurrence of negative life events, which tend to be characterized by optimism. In Study 1, 80 undergraduates (mean age 19.5 yrs) completed a questionnaire on preventive behaviors and intentions. Ss judged 10 negative events while the comparison procedure, number of categories, and order of judgment were varied. In Study 2, 488 Ss (mean age 21.3 yrs) completed 2 questionnaires on the same 10 events, with a 1-wk interval between the 2. Preceding judgment, comparison procedures and time-lag were varied. Estimation using other-as-standard led to more optimism than using self-as-standard. Comparing self to others also led to more optimism than the reverse. Results show that transient reference points may reduce the tendency to see the self as better than others."