Schedules of Reinforcement AP Psychology Mr. Boyd

Reinforcement Schedules Continuous Reinforcement: Reinforces the desired response each time it occurs. Partial Reinforcement: Reinforces a response only part of the time. Though this results in slower acquisition in the beginning, it shows greater resistance to extinction later on. OBJECTIVE 14| Discuss the strengths and weaknesses of continuous and partial reinforcement schedules, and identify four schedules of partial reinforcements.

Schedules of Reinforcement Continuous reinforcement refers to reinforcement being administered to each instance of a response Partial reinforcement (intermittent) lies between continuous reinforcement and extinction

An Example of Continuous Reinforcement Each instance of a smile is reinforced

Schedules of Reinforcement Continuous Reinforcement – A schedule of reinforcement in which every correct response is reinforced. Partial Reinforcement – One of several reinforcement schedules in which not every correct response is reinforced. Which method do you think is used more in real life?

Schedules of Reinforcement Ratio Version – having to do with instances of the behavior. Ex. – Reinforce or reward the behavior after a set number or X many times that an action or behavior is demonstrated. Interval Version – having to do with the passage of time. Ex. – Reinforce the participant after a set number or X period of time that the behavior is displayed.

4 Basic Schedules of Reinforcement Fixed-interval schedule Variable-interval schedule Fixed-ratio schedule Variable-ratio schedule

Fixed-Interval Schedule Fixed-interval schedule – A schedule in which a fixed amount of time must elapse between the previous and subsequent times that reinforcement will occur. No response during the interval is reinforced. The first response following the interval is reinforced. Produces an overall low rate of responding Ex. I get one pellet of food every 5 minutes when I press the lever

Fixed Interval Reinforcement

Variable-Interval Schedule Variable-interval Schedule – A schedule in which a variable amount of time must elapse between the previous and subsequent times that reinforcement is available. Produces an overall low consistent rate of responding. Ex. – I get a pellet of food on average every 5 minutes when I press the bar.

Variable Interval Reinforcement

Fixed-Ratio Schedule Fixed-ratio Schedule – A schedule in which reinforcement is provided after a fixed number of correct responses. These schedules usually produce rapid rates of responding with short post-reinforcement pauses The length of the pause is directly proportional to the number of responses required Ex. – For every 5 bar presses, I get one pellet of food

An Example of Fixed Ratio Reinforcement Every fourth instance of a smile is reinforced

Fixed Ratio Reinforcement

Variable-Ratio Schedule Variable-ratio Schedule – A schedule in which reinforcement is provided after a variable number of correct responses. Produce an overall high consistent rate of responding. Ex. – On average, I press the bar 5 times for one pellet of food.

An Example of Variable Ratio Reinforcement Random instances of the behavior are reinforced

Variable Ratio Reinforcement

TYPE MEANING OUTCOME Fixed Ratio Variable Ratio Fixed Interval Reinforcement depends on a definite number of responses Activity slows after reinforcement and then picks up Variable Ratio Number of responses needed for reinforcement varies Greatest activity of all schedules Fixed Interval Reinforcement depends on a fixed time Activity increases as deadline nears Variable Interval Time between reinforcement varies Steady activity results

Comparisons of Schedules of Reinforcement FORM OF REWARD INFLUENCE ON PERFORMANCE EFFECTS ON BEHAVIOR SCHEDULE Fixed interval Reward on fixed time basis Leads to average and irregular performance Fast extinction of behavior Fixed ratio Reward tied to specific number of responses Leads quickly to very high and stable performance Moderately fast extinction of behavior Variable interval Reward given after varying periods of time Leads to moderately high and stable performance Slow extinction of behavior Variable ratio Reward given for some behaviors Leads to very high performance Very slow extinction of behavior