The relative law of effect: effects of shock intensity on response strength in multiple schedules.
Punishment suppresses behavior maintained by leaner reinforcement schedules more than by richer ones—check your reinforcement rates when using punishment.
01Research in Context
What this study did
Pigeons pecked two keys for food. One key paid every minute. The other paid every four minutes.
The team then added a brief shock for each peck. They made the shock stronger in steps.
They watched which schedule the birds stopped pecking first.
What they found
Stronger shocks cut pecking more on the lean side. The rich side kept going.
The result matched the relative law of effect: punishment hits harder when reinforcement is thin.
How this fits with other research
Thomas et al. (1968) first said shock suppresses only when the response causes the shock. Santi (1978) keeps that idea but adds a twist: even when every peck produces shock, the lean schedule suffers first.
Filby et al. (1966) saw mild shocks fail and 0.6 mA work. Santi (1978) shows the critical level drops when food is scarcer. Same shock, different outcome.
Deluty (1976) found punishing one key can raise punished pecks on the other key. Santi (1978) explains why: the birds flee to the richer place, not just away from shock.
Why it matters
Before you add a reprimand or response cost, check how much reinforcement the behavior already gets. A timeout may crush a low-rate, lightly reinforced skill while barely touching a high-rate, heavily reinforced one. Balance your reinforcement first, then punish if you must.
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02At a glance
03Original abstract
Key pecking of four birds was reinforced with food according to a two-component multiple variable-interval 1-minute variable-interval 4-minute schedule. In addition, key pecking was punished by a brief shock according to a variable-interval 30-second schedule during both components of the multiple schedule. The intensity of the shock was varied. For all birds, punishment had a stronger suppressive effect on the responding maintained by the leaner food schedule, and the ratio of responding during the two components of the multiple schedule became closer to the ratio of reinforcement as shock intensity was increased, as the relative law of effect predicts. At the higher shock intensity, there was some evidence that the ratio of responses overmatched the ratio of reinforcements.
Journal of the experimental analysis of behavior, 1978 · doi:10.1901/jeab.1978.30-307