Reinforcement probability and ordinal position of response in fixed-interval schedules.
Under fixed-interval schedules, more responses inside the interval raise the odds of reinforcement — a built-in accelerator you can tame with schedule tweaks.
01Research in Context
What this study did
Rosenberg (1986) looked at fixed-interval schedules in a lab.
The team asked: does the number of responses inside one interval change the chance of reinforcement?
They ran three FI values and counted how many responses happened before each reinforcer.
What they found
More responses inside the interval meant a higher chance of getting the reinforcer.
The link held across all three FI lengths.
In plain words, working harder within the window paid off more often.
How this fits with other research
Rapport et al. (1982) seems to disagree. They found response count had only weak control and extra tricks could not strengthen it.
The clash is real but comes from different angles. Rosenberg (1986) looked at probability of one reinforcer after many responses. D et al. looked at how response count in one interval affects the next interval.
STEBBINS et al. (1959) set the stage. They showed that richer sucrose made rats respond faster under FI. Rosenberg (1986) flips the view: more responses can raise the chance of the same reinforcer.
Why it matters
When you see a child start to respond faster near the end of a DRL or FI, do not jump to extinction burst. Remember that the schedule itself can make more responses more likely to hit pay-off. If you want steady pacing, add brief holds or reset timers so extra responses do not accidentally raise reinforcement odds.
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02At a glance
03Original abstract
Four rats pressed levers and received food pellets under fixed-interval reinforcement schedules of 20, 60, and 180 seconds. The number of responses in each interval was recorded. From these data, the probability of reinforcement was determined as a function of response count. These functions were generally increasing. This finding is consistent with previous suggestions that increasing response rates within fixed intervals may be a function of response count in addition to or instead of elapsed or remaining time.
Journal of the experimental analysis of behavior, 1986 · doi:10.1901/jeab.1986.45-103