Transcript Powerpoint

PSY402
Theories of Learning
Chapter 7 – Theories and
Applications of Appetitive
Conditioning
Operant Conditioning
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The nature of reinforcement:
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Premack’s probability differential theory
Response deprivation theory
Behavioral economics:
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Behavioral allocation – blisspoint
Choice behavior – Herrnstein’s
matching law.
Momentary maximization theory
Delay-reduction theory
Probability-Differential Theory
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Premack – a reinforcer can be any
activity that is more likely to occur
than the reinforced behavior.
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Manipulators vs eaters
High probability behaviors can be
used as reinforcers of low
probability behaviors.
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Frequency of the reinforcer decreases
when it is made contingent on another
response.
Response Deprivation Theory
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Timberlake & Allison – deprivation
occurs when an activity is used as a
reinforcer and is not freely emitted.
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The activity is reinforcing because it
satisfies the deprivation created.
The animal tries to return to its predeprivation level of responding.
Activities can be reinforcing even if
their baselines were not higher.
Behavioral Allocation
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Blisspoint (paired basepoint) – the
free operant level of two responses.
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Unrestricted responding with two
choices of behaviors.
Blisspoint is used to figure out how
much behavior an animal will
engage in to obtain a reward.
Animals try to get as close to the
blisspoint as possible.
Problems with Contingencies
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Blisspoint is established by looking
at behavior before a contingency is
established.
The established contingency must
take blisspoint into account or it
may not increase desired behavior.
Choice Behavior
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Herrnstein’s matching law –
describes how animals act when
they have two or more choices.
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Different responses have different
schedules of reinforcement.
Responding to each choice is
proportionate to the reinforcement for
each choice – after learning.
This can be expressed mathematically.
Mathematical Expression
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The formula for the matching law
is:
where R1 and R2 are the rates of
response for two alternative responses
And r1 and r2 are rates of reinforcement
for those responses
Delayed Gratification
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Why does anyone choose a smaller
reward part of the time?
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Animals and people typically choose a
small immediate reward over a larger
delayed reward.
Large rewards are selected when:
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The choice is made in advance of
reward.
Reinforcers are not visible or reward is
already present (pleasurable activity).
Complexities of the Matching Law
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Maximizing law – sometimes the
aim is to obtain as many rewards as
possible.
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Explains FR-10 vs FR-40 schedules.
Doesn’t work for VI vs VR schedules.
Momentary maximization theory –
choose best alternative at the time.
Delay reduction theory – choose
what will get the reward the fastest.
Contingency Management
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Assessment phase – determine the
frequency of behavior and the
situations in which it occurs.
Contracting phase – specifies the
relationship between responding
and reinforcement.
Management phase – implement
the contract and evaluate results.