PS262 Chapter Notes -Detection Theory, Receiver Operating Characteristic
Document Summary
Difference in response criterion - difference between ways of responding. E. g. only saying you saw the light if you were absolutely certain, or saying you saw the light if you were only pretty sure. Signal detection theory - used to deal with this problem. In a psychophysical procedure, at least five different stimulus intensities are presented and a stimulus is presented on every trial. Signal detection experiment differs from a classical psychophysical experiment in two ways (in a signal detection experiment):: 1. only one stimulus intensity is presented. 2. on some of the trials, no stimulus is presented. Hit - in signal detection terminology, saying yes when a stimulus is present. Miss - saying no when a stimulus is present. False alarm - saying yes when there is no stimulus. Correct rejection - saying no when there is no stimulus. E. g. win for a hit, lose for a miss. Person"s sensitivity is indicated by roc curve.