| A. Fixed-Ratio Schedule | I. Reinforcement is given after a specific, predetermined number of responses |
| B. Variable-Ratio Schedule | II. Reinforcement is given after an unpredictable number of responses, leading to a high, steady rate of response |
| C. Fixed-Interval Schedule | III. Reinforcement is given after a specific, consistent amount of time, regardless of the number of responses |
| D. Variable-Interval Schedule | IV. Reinforcement is given at unpredictable time intervals, producing a moderate, steady rate of response |
1
A-I, B-II, C-III, D-IV
2
A-IV, B-II, C-III, D-I
3
A-II, B-I, C-III, D-IV
4
A-I, B-IV, C-II, D-III