ABA Fundamentals

Choice as time allocation.

Baum et al. (1969) · Journal of the experimental analysis of behavior 1969
★ The Verdict

Reinforcement rate sets how minutes are spent, so adjust payoffs to shift time toward target skills.

✓ Read this if BCBAs who run concurrent schedules or see clients splitting time between tasks.
✗ Skip if Clinicians working solely with single-response DTT where time allocation is fixed.

01Research in Context

01

What this study did

Researchers placed pigeons in a box with two keys.

Each key paid off on a different schedule.

The birds could hop and peck as they wished.

The team logged every second the birds spent on each side.

02

What they found

Time on each side almost matched the payoff rate.

If the left key paid 70 percent of the food, birds stayed about 70 percent of the time there.

They also showed a small right-side habit that never went away.

03

How this fits with other research

Deluty et al. (1978) swapped food for mild shock.

Rats still matched their time to the shock rate, proving the rule works for bad events too.

Dugan et al. (1995) used hens that had to peck one key and push a door for the other key.

The different moves created a built-in bias, yet the matching equation still predicted the split.

Mellitz et al. (1983) later showed birds don’t always match; sometimes they pick the option most likely to pay next.

Both papers are right: matching describes long-run totals, while momentary maximizing explains snap choices.

04

Why it matters

Your client’s time is the same limited currency.

If you want more time on math and less on escape, raise the payoff rate for math.

Check for bias: a favorite seat or toy can act like the pigeons’ right-side pull.

Track minutes, not just correct responses, to see the true allocation.

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→ Action — try this Monday

Count how many reinforcers you deliver for each task in a 10-minute period, then rebalance to favor the goal behavior.

02At a glance

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

03Original abstract

When pigeons' standing on one or the other side of a chamber was reinforced on two concurrent variable-interval schedules, the ratio of time spent on the left to time spent on the right was directly proportional to the ratio of reinforcements produced by standing on the left to reinforcements produced by standing on the right. The constant of proportionality was less than unity for all pigeons, indicating a bias toward the right side of the chamber. The biased matching relation obtained here is comparable to the matching relation obtained with concurrent reinforcement of key pecks. The present results, together with related research, suggest that the ratio of time spent in two activities equals the ratio of the "values" of the activities. The value of an activity is the product of several parameters, such as rate and amount of reinforcement, contingent on that activity.

Journal of the experimental analysis of behavior, 1969 · doi:10.1901/jeab.1969.12-861