Banna, K.M. & Newland, M.C. (2009).
Within-session transitions in choice: A structural and quantitative analysis.
Journal of the Experimental Analysis of Behavior, 91, 319-335.
The present study used within-session transitions between two
concurrent schedules to evaluate choice in transition. Eight
female Long-Evans rats were trained to respond under concurrent
schedules of reinforcement during experimental sessions that
lasted 22 hr. The generalized matching equation was used to
model steady-state behavior at the end of each session, while
transitional behavior that emerged following the change in
reinforcement schedules was modeled using a logistic equation.
The generalized matching and logistic equations were
appropriate models for behavior generated during single-session
transitions. A local analysis of behavior on the two response
alternatives during acquisition was used to determine the source
of preference as revealed in response ratios. The number
of "low-response" visits, those containing three
to five responses, remained stable. Preference ratios
largely reflected a sharp increase in the number of visits
with long response bouts on the rich alternative and a
decrease in the number of such visits to the leaner alternative.
Key words: choice, concurrent schedules, acquisition, transitions, lever press, rats