Learning and Behavior: Operant Conditioning Edward Thorndike ( )

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1 Learning and Behavior: Operant Conditioning Edward Thorndike ( ) Introduced experimental method Was interested in animal learning. Put animals in boxes and watched how long it took them to escape

2 Thorndike s Puzzle Boxes Cat in box Thorndike s law of effect Consequences of an act determine whether it will be repeated in the future Behaviors followed by positive consequences are more likely to be repeated Behaviors followed by negative consequences are less likely to be repeated B. F. (Fred) Skinner ( ) Highly creative & imaginative maverick Systematized prior work Great inventor Skinner box Cumulative recorder

3 Skinner box Rat Operant Conditioning Behavior operatingon the environment Learning about the consequences of behavior: IF-THEN relations between behavior and a stimulus that comes after it Operant Behavior Examples of IF-THEN relations IF the key is pressed, THEN food is presented.

4 Operant Behavior IF the key is turned, THEN the car starts. Operant Behavior IF the dog s tail is pulled, THEN the dog bites. Operant Conditioning Reinforcement Any stimulus that increases behavior Punishment Any stimulus that decreases behavior

5 Operant Conditioning Reinforcement & Punishment Present Stimulus + Remove Stimulus - Increases Behavior Positive Reinforcement (give money) Negative Reinforcement (take away chores) Decreases Behavior Positive Punishment (give chores) Negative Punishment (take away money) Similar consequences affect behavior differently. Billy enjoys camping. The last time he camped out, some older kids snuck up to his tent while he was sleeping and threw a bucket of cold water on him. Billy has not camped-out for three weeks. What is Camping the behavior? Increasing Decreasing What Bucket is the Consequence? of Water Adding Subtracting

6 Your dog s barking really upsets you. So every time she barks a collar you put on her gives her a shock. She stops barking. What is Camping the behavior? Increasing Decreasing What Bucket is the Consequence? of Water Adding Subtracting Your dog hates strangers, so she barks at them. This makes them leave. Her barking in the presence of strangers increases. What is Camping the behavior? Increasing Decreasing What Bucket is the Consequence? of Water Adding Subtracting Your mother is nagging you to clean the house. After a while you decide to clean the house so that you don t have to listen to her anymore. In the future you decided to clean the house more often to avoid her nagging. What is Camping the behavior? Increasing Decreasing What Bucket is the Consequence? of Water Adding Subtracting

7 Your dog jumps on you to get attention. Every time the dog jumps on you, you turn your back or leave the room. The dog s jumping up behavior decreases. What is Camping the behavior? Increasing Decreasing What Bucket is the Consequence? of Water Adding Subtracting Shaping Desired behavior is not always available to be reinforced So reinforce closer & closer approximations to desired behavior Elephant training

8 What are reinforcers? Primary reinforcers Food if hungry Fluid if thirsty Shelter Sex Secondary reinforcers Things that are often linked with primary reinforcers acquire the ability to act as reinforcers themselves

9 Using Reinforcement to Boost Job Performance All salesclerks were observed for a 20-day baseline period. Then, half were given cash bonuses for good performance, half were not. The ones given cash bonuses improved job performance. Schedules of Reinforcement But does every response need to receive a reinforcer to increase the behavior? What happens if you only reinforce some of the behavior? OR you reinforce the behavior every 10 minutes? Types of Schedules Four basic schedule types: Fixed Ratio (FR) Variable Ratio (VR) Fixed Interval (FI) Variable Interval (VR)

10 Types of Schedules Ratio: Reinforcement depends on certain number of responses Interval: Reinforcement depends on the first response after a certain period of time from the last reinforcer Types of Schedules Fixed: Requirements for reinforcement do not change from one reinforcer to the next Variable: Requirements for reinforcement vary from one reinforcer to the next Fixed-Ratio (FR) Schedules Real-life example: piecework

11 Variable-Ratio (VR) Schedules Real-life example: slot machines Fixed-Interval (FI) Schedules Real-life example: checking clock Variable-Interval (VI) Schedules Real-life example: waiting for the big wave

12 Cindy is practicing her golf putting. On the average, it takes her four putts before the ball goes in the hole. This is an example of a schedule of reinforcement A. Fixed ratio B. Variable ratio C. Fixed interval D. Variable interval Francis sells jewelry to a local gift shop. Each time he completes 10 pairs of earrings, the shopkeeper pays him for them. This is an example of a schedule of reinforcement. A. Fixed ratio B. Variable ratio C. Fixed interval D. Variable interval Sandra s mail is delivered every day at 10:00. She checks her mailbox several times each morning, but only finds mail the first time she checks after 10:00. This is an example of a schedule of reinforcement A. Fixed ratio B. Variable ratio C. Fixed interval D. Variable interval

13 Paula is an eager third-grader, and loves to be called on by her teacher. Her teacher calls on her approximately once each period, although Paula is never sure when her turn will come. This is an example of a schedule of reinforcement A. Fixed ratio B. Variable ratio C. Fixed interval D. Variable interval Difference between operant and classical conditioning Classical Conditioning Stimulus Behavior Difference between operant and classical conditioning Operant Conditioning Behavior Stimulus

14 What did we learn? History. Operant conditioning and how it is different from classical conditioning. Shaping Difference between reinforcement and punishment. Types of reinforcers. Differences between the schedules of reinforcement.