Sh. Mitchell et al., EFFECTS OF PRICE, OPENNESS OF THE ECONOMY AND MAGNITUDE OF THE ALTERNATIVE REINFORCER ON RESPONDING FOR CAFFEINATED COFFEE, Human psychopharmacology, 10(1), 1995, pp. 39-46
Consumption of a commodity is influenced by various factors. This expe
riment examined three factors: unit price, 'openness' of the economy,
and magnitude of an alternative reinforcer. Subjects earned caffeinate
d coffee and money by responding on concurrent random-ratio (RR) sched
ules. Coffee price was varied by changing the coffee schedule from RR1
. 3 to RR16, while holding the money schedule constant (RR4). Opennes
s of the economy was varied by changing the amount of unearned coffee
provided during a 2-h post-task period (0, 1 . 5 or 3 free cups). The
magnitude of the alternative reinforcer was varied by allowing subject
s to earn an average of $2.00 or $6.00 for responding on the money sch
edule. Number of responses for coffee and amount of coffee earned vari
ed inversely with the openness of the economy, but were unaffected by
the amount of money available. Analysing the demand for coffee as a fu
nction of coffee price revealed that coffee was a less elastic commodi
ty when the economy was closed than when it was more open. Within the
range of parameters tested here, price of caffeinated coffee and openn
ess of the economy strongly affected responding in humans, whereas the
magnitude of an alternative monetary reinforcer had only limited effe
cts.