The theory of general acuity: A psychophysical application to noncognitive measurement free from introspective self-report.

Abstract

The measurement of non-cognitive constructs (e.g., openness, honesty, and selfesteem) using introspective self-report has often been criticized for its vulnerability to validity-reducing response distortion. In this article, we present a theory of general acuity as an extension of Leeds's (2012Leeds's ( , 2018 theory of cognitive acuity. General acuity theory proposes that the higher a person's standing on any mentally held construct, the more sensitive the person will be to distinctions in phenomena associated with that construct. If true, then it may be possible to measure standing on any construct by observing the person's sensitivity to distinctions in many paired instances of the phenomena. We thus define general acuity as sensitivity to distinctions in construct-relevant (CR) phenomena as evidence of one's standing on that construct and point out that the response demand being made is based on signal detection and not introspective self report. We report three studies of the (a) customer service orientation of Spanish sales personnel, (b) agreeableness of U.S. college students, and (c) conscientiousness of U.S. public service coordinators. In each study, we used paired CR statements and adjectives to present respondents with a series of CR signal contrasts to detect. We used psychophysical methods to estimate respondents' construct signal sensitivity (i.e., acuity) and to assess test attentiveness and show that CR acuity is related to independent measures of the target constructs. We present the psychophysical framework, measurement procedures, and criterion/construct-related validity evidence for a general acuity theory, making the case for a common psychometric theory underpinning all cognitive and non-cognitive measurement.