Ratio schedules yield reinforcers on the basis of number of responses made.After a specified number of responses have been produced, the reinforcement isadministered. Time is not a factor.

There are two major types of ratio schedules.

A Variable Ratio Schedule produces rewards irregularly. Thecriteria for reinforcement changes, it rotates around an average number ofresponses. The amount of work required per reinforcement varies somewhatrandomly within certain limits (Carpenter, 1974).

Examples

1. A Slot machine yields returns on an irregular basis.

2. Pigeons will peck for hours at a rate of five times per second. Thefirst reinforcer is given after pecking three times, then seven times, then fivetimes, then four times and then one time.

A Fixed Ratio Schedule requires a constant number of responses beforethe reinforcer is delivered. This schedule produces a single reward for aspecifiednumber of responses.

Examples

1. A rat will be rewarded after he presses the bar three times.

2. A student will receive a free homework pass after completing fivehomework assignments with at least a grade of 90%.