THE SAME-DIFFERENT METHOD: POSITIVE EFFECTS OF REDUCED MEMORY LOAD VERSUS NEGATIVE EFFECTS OF UNCONTROLLED Τ-CRITERION VARIATION, USING FORCED-CHOICE METHODS AS A COMPARISON

摘要

The positive effects of reduced memory load for the same-different method were tested against the negative effects of judge τ-criterion variation, using the forcedchoice triangle, duo-trio and ABX methods for comparison. The tests were carried out under nonlaboratory conditions in an everyday dining area, with mango juices as the stimuli. A control experiment involving sequential sensitivity analysis was performed to monitor carry-over effects. The results of the main experiment showed no significant differences in the low d'values for the forced-choice methods, while a zero value was recorded for the same-different method. This was due to variability in the τ-criterion causing the overall value to be large enough to elicit, for sufficiently confusable stimuli, more incorrect than correct responses, when the two stimuli in the test were different.