MARKOV CHOICE PROCESSES IN SIMULTANEOUS MATCHING-TO-SAMPLE AT DIFFERENT LEVELS OF DISCRIMINABILITY

Decision and choice processes by pigeons were studied in a simultaneous matching-to-sample task. In order to view the recessed stimuli, the pigeons had to move in front of the pecking keys. They frequently moved back and forth between the comparison stimuli before choosing one of them as the match to the sample stimulus. These looking and choice responses were studied and recorded for five different discriminability levels, from near perfect (92%) to near chance (56%) performance, by changing the wavelength difference of the stimuli to be discriminated. The decision process was shown to be Markovian throughout the discriminability range, and the decision strategy based upon a Markov process is contrasted with other potential decision strategies. © 1990 Psychonomic Society, Inc.