ABA Fundamentals

Determinants of pausing under variable-ratio schedules: Reinforcer magnitude, ratio size, and schedule configuration.

Blakely et al. (1988) · Journal of the experimental analysis of behavior 1988
★ The Verdict

The tiniest ratio in a VR schedule decides whether bigger reinforcers will shorten pauses or quicken responses.

✓ Read this if BCBAs building or thinning VR token boards, slot-machine style DRL, or piece-rate work systems.
✗ Skip if Clinicians who only use fixed-ratio or time-based schedules.

01Research in Context

01

What this study did

Bachman et al. (1988) asked how reinforcer size changes pausing on variable-ratio schedules.

They tested different ratio sizes and schedule shapes in a lab setting.

The goal was to see which part of the schedule controls the pause after reinforcement.

02

What they found

The smallest ratio step in the schedule, not the average, set the pause length.

Bigger reinforcers only shortened pauses when the smallest ratio was also small.

If the smallest ratio stayed large, bigger reinforcers did little to speed responding.

03

How this fits with other research

Glover et al. (1976) found that richer reinforcers and larger VR sizes both lengthen pauses.

E et al. seem to disagree, but the clash disappears once you look at the smallest ratio.

The 1976 study used fixed steps, so the smallest ratio was always big; E et al. varied it.

STEBBINROSS et al. (1962) showed thicker reinforcement cuts latency; E et al. add that the schedule shape decides where that speed shows up.

04

Why it matters

When you thin a VR schedule, watch the lowest requirement, not the average.

Keep that low step small if you want bigger tokens, snacks, or praise to energize the client.

Check your data logs for the smallest ratio delivered; adjust that first before adding more tasks.

Free CEUs

Want CEUs on This Topic?

The ABA Clubhouse has 60+ free CEUs — live every Wednesday. Ethics, supervision & clinical topics.

Join Free →
→ Action — try this Monday

Find the smallest ratio in your client’s VR program; if it’s above 3, drop it and watch response speed rise.

02At a glance

Intervention
not applicable
Design
single case other
Population
not specified
Finding
not reported

03Original abstract

Pigeons pecked a key under two-component multiple variable-ratio schedules that offered 8-s or 2-s access to grain. Phase 1 assessed the effects of differences in reinforcer magnitude on postreinforcement pausing, as a function of ratio size. In Phase 2, postreinforcement pausing and the first five interresponse times in each ratio were measured as a function of differences in reinforcer magnitude under equal variable-ratio schedules consisting of different configurations of individual ratios. Rates were also calculated exclusive of postreinforcement pause times in both phases. The results from Phase 1 showed that as ratio size increased, the differences in pausing educed by unequal reinforcer magnitudes also increased. The results of Phase 2 showed that the effects of reinforcer magnitude on pausing and IRT durations were a function of schedule configuration. Under one configuration, in which the smallest ratio was a fixed-ratio 1, pauses were unaffected by magnitude but the first five interresponse times were affected. Under the other configuration, in which the smallest ratio was a fixed-ratio 7, pauses were affected by reinforcer magnitude but the first five interresponse times were not. The effect of each configuration seemed to be determined by the value of the smallest individual ratio. Rates calculated exclusive of postreinforcement pause times were, in general, directly related to reinforcer magnitude, and the relation was shown to be a function of schedule configuration.

Journal of the experimental analysis of behavior, 1988 · doi:10.1901/jeab.1988.50-65