Hall, G. A., & Lattal, K. A. (1999).
Reward density and variable- interval schedule performance in an open economy.
Journal of the Experimental Analysis of Behavior,
72, 341-354.
There is no general agreement regarding the form of the relation
between response rate and reinforcement rate when single
schedules of reinforcement are studied in an open economy. The
present study assessed the form of this relation using reward
density, which incorporates both reinforcement rate and duration
of access to food, as an independent variable. Reward density was
manipulated with 4 pigeons by changing the value of the
variable-interval schedule, the hopper duration, or both. The
relations between response rate and reward density were sharply
rising and hyperbolic in 3 of 4 pigeons, replicating results
obtained by Catania and Reynolds (1968). Because eating
efficiency was lower in conditions that provided longer hopper
durations, programmed reward densities differed from obtained
reward densities. When response rates were examined as a function
of obtained reward densities, the same relations were
demonstrated more strongly. In further clarifying the relation
between response rate and reward density in an open economy,
these results lend support to the conclusion that open and closed
economies yield different behavioral effects.
Key words: reward density, open economy, food hopper duration,
variable-interval schedule, reinforcement rate, key peck, pigeons