Proceedings of the Annual Meeting of the Cognitive Science Society

This paper considers the class of hypothesis testing tasks purporting to demonstrate pseudodiagnosticity. It argues that, as has recently been done with other hypothesis testing tasks, pseudodiagnosticity tasks may be re-analysed in terms of people's background beliefs about the probability of their evidential items and the utility of their various test outcomes. A sample analysis of a simplified task is presented along with the results of an experiment which demonstrate that subjects' behaviour corresponds to the prescriptions of the analysis. How the sample analysis might be applied to the standard pseudodiagnosticity task is discussed as are the implications of the results for current accounts of the effects of subjective probability on human hypothesis testing.