A comparison of response patterns on fixed-, variable-, and random-ratio schedules.
Fixed, variable, and random ratios can yield the same overall speed, but only fixed ratios lock learners into long post-reinforcement pauses.
01Research in Context
What this study did
Reid et al. (1987) tested three ratio schedules side by side. They used fixed-ratio, variable-ratio, and random-ratio with the same overall ratio size.
Each pigeon worked on all three schedules. The team recorded every peep and pause.
What they found
Total response rates looked the same across schedules. The birds pecked about equally fast.
Fixed-ratio schedules caused long post-reinforcement pauses. Variable and random schedules broke up the pauses, creating a run-pause-run pattern.
How this fits with other research
Powell (1968) showed that bigger fixed ratios make pauses longer. Reid et al. (1987) add that schedule type, not just size, shapes the pause.
Baron et al. (1968) found pigeons prefer variable ratios. The new data explain why: fixed ratios trap the bird in a long pause after every reinforcer.
Sturmey et al. (1996) later showed the smallest ratio in a variable schedule drives choice. Together these papers tell us to watch the shortest component, not the average.
Why it matters
When you build token boards or work schedules, choose variable or random ratios to keep clients responding. Fixed ratios are easy to program but create dead time after each payoff. If you must use fixed ratios, keep them small or mix in praise during the pause to bridge the gap.
Want CEUs on This Topic?
The ABA Clubhouse has 60+ free CEUs — live every Wednesday. Ethics, supervision & clinical topics.
Join Free →Switch one fixed-ratio program to a variable ratio with the same average and measure if responding stays smoother.
02At a glance
03Original abstract
The behavior of individual pigeons on fixed-ratio, variable-ratio, and random-ratio schedules was examined. Within each type of ratio schedule the size of the ratio was varied in an irregular sequence. At various ratio sizes (5, 10, 40, 80) no differences were found among overall response rates (postreinforcement pause plus running response rate) as a function of ratio type. This similarity in overall response rates held despite noticeable differences in the microstructure of performance both within and across subjects; the primary performance difference on the three types of ratio schedules was the relatively longer postreinforcement pause duration on the fixed-ratio schedule. We concluded that the gross temporal characteristics of performance determined by the relative weightings of the postreinforcement pause and running response rate were primarily controlled by the type of ratio schedule (fixed, variable, or random), whereas the overall rate of responding was controlled by the size of the ratio.
Journal of the experimental analysis of behavior, 1987 · doi:10.1901/jeab.1987.48-395