Set ambiguity: A key determinant of reliability and validity in the picture story exercise

摘要

The picture story exercise (PSE), in which participants write imaginative stories in response to motivationally-arousing images, is the most commonly-used tool for the assessment of implicit motives. Despite decades of research into the qualities of effective individual picture cues, much less is known about the desirable properties of overall picture sets. The present research highlights a previously undocumented methodological consideration-set ambiguity-which has important implications for the reliability and validity of the PSE. In a four-part study of 74 undergraduates, motive scores derived from an ambiguous picture set comprising cues that vary in motivational focus displayed greater test-retest reliability, convergent validity, and predictive validity than those derived from an unambiguous picture set. Researchers are therefore advised to consider set ambiguity when selecting images for use in PSE research.