Concepts · Domain B

Ratio vs. interval schedules

The difference in short

Ratio and interval schedules define when the reinforcer is delivered. In a ratio schedule, it depends on the number of responses. In an interval schedule, it depends on time passing and then a response. Ratio = how many responses; interval = how much time plus one response.

Quick comparison

Ratio scheduleInterval schedule
OperationReinforcer depends on the number of responsesDepends on time passing + one response
EffectProduces high response ratesProduces steadier rates
ExampleYou're paid for every 10 parts you assemble.You check email and only sometimes is there something new.

How to tell them apart

  1. Does the reinforcer depend on HOW MANY responses (ratio) or on TIME passing (interval)?

Examples

Ratio schedule
You're paid for every 10 parts you assemble.
Interval schedule
You check email and only sometimes is there something new.

Frequently asked

Why do ratio schedules produce more responses?
Because the reinforcer depends directly on how much you respond: more responses, more reinforcers. On interval schedules, extra responding doesn't speed up the reinforcer.

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