THE CALIBRATION AND RESOLUTION OF CONFIDENCE IN PERCEPTUAL JUDGMENTS

Confidence rating based calibration and resolution indices were obtain ed in two experiments requiring perceptual comparisons and in a third with visual gap detection. Four important results were obtained. First , as in the general knowledge domain, subjects were underconfident whe n judgments were easy and overconfident when they were difficult. Seco nd, paralleling the clear dependence of calibration on decisional diff iculty, resolution decreased with increases in decision difficulty ari sing either from decreases in discriminability or from increasing dema nds for speed at the expense of accuracy. Third, providing trial-by-tr ial response feedback on difficult tasks improved resolution but had n o effect on calibration. Fourth, subjects can accurately report subjec tive errors (i.e., trials in which they have indicated that they made an error) with their confidence ratings. It is also shown that the pro perties of decision time, conditionalized on confidence category, impo se a rigorous set of constraints on theories of confidence calibration .