Schedules of Operant Conditioning Handout

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Classical/Operant Conditioning
Comparing Classical and Operant Conditioning: What’s the Difference?
In Summary, the processes of generalization, discrimination, extinction, and spontaneous recovery occur in both classical
and operant conditioning. Both types of conditioning depend on associative learning. In classical conditioning, an association is
formed between two stimuli – for example, a tone and food, a white rat and a loud noise, a product and a celebrity. In operant
conditioning, the association is established between a response and its consequences – studying hard and a high-test grade, or in
the world of rats, bar pressing and food.
In classical conditioning, the focus is on what precedes the response. Pavlov focused on what led up to the salivation in his
dogs, not on what happened after they salivated. In operant conditioning, the focus is on what follows the response. If a rat’s bar
pressing or your studying is followed by a reinforcer, that response is more likely to occur in the future.
Generally, in classical conditioning, the subject is passive and responds to the environment rather than acting on it. A loud
noise evokes fear in a baby. In operant conditioning, the subject is active and operates on the environment. Children do something
to get their parents’ attention or their praise.
Characteristics
Types of association
State of subject
Focus on attention
Types of response involved
Bodily response involved
Range of responses
Responses learned
Classical and Operant Conditioning Compared
Classical Conditioning
Operant Conditioning
Between two stimuli
Between a response and its
consequence
Passive
Active
On what precedes response
On what follows response
Involuntary or reflexive response
Voluntary response
Internal responses: emotional and
External responses: muscular and
reflexive reactions
skeletal movement and verbal
responses
Relatively simple
Simple to highly complex
Emotional reactions: fear, likes, dislikes
Goal-oriented responses
The Effects of Reinforcement and Punishment
Reinforcement
Punishment
(Increases or strengthens a behavior)
(Decreases or suppresses a behavior)
Positive reinforcement (Adding a Positive)
Positive Punishment/Punishment by Application (Adding
Presenting food, money, praise, attention, or
a negative)
other rewards
Delivering a pain-producing or otherwise aversive stimulus,
such as a spanking or an electric shock.
Negative Reinforcement (Subtracting a Negative) Negative Punishment/Punishment by Removal
Removing or terminating some pain-producing or (Subtracting a positive)
otherwise aversive stimulus, such as an electric
Removing some pleasant stimulus or taking away
shock
privileges such as TV watching or use of automobile. Ex.
Grounding or Time Outs.
Reinforcement Schedule Compared
Pattern of Responses
Schedule of
Reinforcement
Fixed-ratio
Schedule
Response Rate
Variable-ratio
Schedule
Fixed-interval
Schedule
Variable-interval
Schedule
Highest response
rate
Lowest response
rate
Moderate
Very high
Steady response with low ratio.
Brief pause after each
reinforcement with very high
ratio.
Constant response pattern, no
pauses
Long pause after reinforcement,
followed by gradual acceleration
Stable, uniform response
Resistance to Extinction
The higher the ratio, the more
resistance to extinction.
Most resistance to extinction.
The longer the interval, the more
resistance to extinction
More resistance to extinction
than fixed-interval schedule with
same average interval
Schedules of Reinforcement
RATIOS = RESPONSES
•
•
Fixed Ratio (FR) – Reinforcement occurs after a fixed number of responses
–
Results in a burst-pause-burst-pause pattern
–
Example: Receiving a free coffee after every ten you buy at Jumping Java
Variable Ratio (VR) – Reinforcement occurs after an average number of responses.
Number of responses
required for reinforcement is unpredictable.
–
Results in high, steady rates of responding with almost no pauses
–
Example: Gambling – you must continue to play the slot machine multiple times if you want to win.
No one knows how many times you’ll have to play before you’re reinforced (win).
INTERVALS = TIME
•
•
Fixed Interval (FI) – A reinforcer is delivered for the first response after a preset time interval has elapsed.
–
Number of responses tends to increase as the time for the next reinforcer draws near then long pause
occurs after reinforcement.
–
Example: If the cookie dough packages says bake for 10 minutes, you don’t start to check until around
the 10 minute mark. The behavior of checking increases around the time of reinforcement (eating the
baked cookies).
Variable Interval (VI) – A reinforcer is delivered for the first response after an average time interval has
elapsed. The interval is unpredictable.
–
Number of responses will be consistently steady because reinforcement could occur at any time.
–
Example: At teacher who wants his class to study their notes every night gives random pop quizzes to
the class. Students study each night because they don’t know when the quiz is actually coming.
Ask Yourself:
•
•
Can the animal speed up its reinforcement by doing the behavior? If YES - Ratio
–
Does the number of times the animal does the behavior vary for reinforcement? Variable
–
Does the animal do the behavior a set number of times for reinforcement? Fixed
Is the example dealing with the amount of time that elapses from when the animal does the behavior till it
gets reinforcement? - Interval
–
Reinforcement will NOT be sped up by doing the behavior more often
–
Does the amount time between the behavior and reinforcement vary? Variable
–
Is the amount of time between the behavior and reinforcement stay the same? Fixed
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