The effect of wanted posters on prospective and retrospective memory.

The experiment tested prospective and retrospective memory for a person pictured on a wanted poster. Participants monitored the videotaped activity of a computer lab; one of their duties involved reporting if they saw a computer hacker. Half viewed a wanted poster of the hacker before the monitoring task and half after. For half the participants, the hacker appeared during monitoring and for half not. A diagnosticity ratio comparing the correct prospective memory identifications with false positive identifications showed that a prospective identification was 3.35 times more likely to be accurate than inaccurate. For those viewing the wanted poster after monitoring, the diagnosticity ratio was 1.21. Based on diagnosticity, a prospective identification had more value than a retrospective identification.