1. Patterns of Responding on Schedules of Reinforcement The Cumulative Record 70 60 50 40 30 20 10 0 Cumulative Responses Time Key measure of behavior: rate of responding This is the number of responses a subject makes in a period of time, like 1 minute.

2. Patterns of Responding on Schedules of Reinforcement 70 60 50 40 30 20 10 0 Cumulative Responses Time A cumulative record shows total (cumulative) responses since the start of the session. By looking at the slope of the line on a cumulative record, you can instantly estimate the rate of responding.

3. Patterns of Responding on Schedules of Reinforcement 70 60 50 40 30 20 10 0 Cumulative Responses Time The steeper the slope, the higher the rate of responding. A steep slope means the subject added a lot of responses to the total during that period of time:

4. Patterns of Responding on Schedules of Reinforcement 70 60 50 40 30 20 10 0 Cumulative Responses Time A B Increase Line A adds more responses to the total than does Line B.

5. Patterns of Responding on Schedules of Reinforcement 70 60 50 40 30 20 10 0 Cumulative Responses Time Increase A straight diagonal line means a constant rate of responding. The number of responses added to the total is always the same from minute to minute.

6. Patterns of Responding on Schedules of Reinforcement 70 60 50 40 30 20 10 0 Cumulative Responses Time A curved line means that the rate of responding is changing. This is because the slopes are changing, and slope = response rate. Negative Acceleration: Response Rate Decreases Over Time

7. Patterns of Responding on Schedules of Reinforcement 70 60 50 40 30 20 10 0 Cumulative Responses Time Here, the slopes get steeper from minute to minute, so the response rate is increasing. Positive Acceleration: Response Rate Increases Over Time

8. Patterns of Responding on Schedules of Reinforcement The Cumulative Record 70 60 50 40 30 20 10 0 Cumulative Responses Time