Jones, J. R., & Moore, J. (1999).
Some effects of intertrial-interval duration on discrete-trial choice.
Journal of the Experimental Analysis of Behavior,
71, 375-393.
Pigeons were trained in Experiment 1 on a discrete-trial
concurrent variable-interval (VI) 1-min VI 3-min schedule, and in
Experiment 2 on a discrete-trial concurree same easily nameable, yet
formally unrelated, pictorial stimuli. Match-to-sample baselines
for four four-member classes were established sequentially (i.e.,
AB-BC-CD), with participants in the rhyme condition trained to
select comparisons whose normative names rhymed with those of the
samples. For the orthogonal condition, class rearrangement was
such that on every trial all available comparisons' names rhymed
with each other, but not with the name of the sample. In the
diagonal condition,mated .75 at short ITIs, but then
decreased toward .50 with longer ITIs. With interdependent
schedules, both preference and obtained relative reinforcement
rate approximated .75 at all ITIs. In both experiments, with both
independent and interdependent schedules, changeover
probabilities for each response in a sequence of up to five
successive responses to a given schedule were variable for
individual birds. The average changeover probabilities for all
birds suggested perseveration rather than a systematic increase
within a given ITI or a systematic trend toward chance responding
as ITI duration increased. Finally, the changeover functions did
not differ when a sequence of responses was calculated to begin
anew after reinforcement rather than with the first response on a
schedule. Taken together, the data were inconsistent with a
theory holding that only local processes underlie choice in
discrete-trial procedures.
Key words: changeover probability, concurrent variable interval
variable interval, molar, molecular, discrete trials, key peck,
pigeons