Suboptimal decision criteria are predicted by subjectively weighted probabilities and rewards


Subjects performed a visual detection task with varied probability of target occurrence and rewards. To maximize monetary gain, observers should bias their responses, choosing one location more often than the other in line with the varied probabilities and rewards. We find that subjects shifted their criterion aware from the neutral position less than required to maximize expected gain (i.e., were *conservative*), but that criterion shifts could best be predicted based on subjective utilities and probability weights.