CONSTRAINED SCALING IN PSYCHOMETRIC MAGNITUDE MAPPING
Constrained scaling is a magnitude scaling method in which the participant is first taught a mapping between the stimulus magnitudes of a specific modality and a numerical response scale. Following the successful completion of this mapping, stimulus magnitudes from a different source are presented without feedback, interspersed with the learned stimuli (which still receive feedback). In addition to providing very low individual variability, constrained scaling can also be used to examine magnitude scaling in a very controlled way. In the present study, we examined the role of training on a perceptual modality and testing on a subjective modality (the subjective utility of money in this case). We argue that constrained scaling can be used to capture individual differences where such differences truly exist, making it a useful tool in psychometric as well as psychophysical research.