CALIBRATION OF PSYCHOPHYSICAL JUDGMENTS - MAGNITUDE ESTIMATES

Calibration has been widely studied in judgments under uncertainty. Mo st of these studies show a clear overconfidence effect. In psychophysi cal judgments calibration has been studied in discrimination tasks and a clear underconfidence effect has been found (Bjorkman, Juslin y Win nan, 1993). Magnitude estimation judgments have not been calibrated si nce a quantitative response cannot be directly considered as right or wrong. This work presents a way to measure the proportion of correct r esponses, at an ordinal level of measurement, using two variants of th e magnitude estimation technique. Calculating calibration we found tha t in both magnitude estimation tasks subjects show an underconfidence effect and no relationship is found between this measure and the goodn ess of fit measure obtained from Stevens' function, its slope, interce pt and mean reaction time.