what is shaping? a process where you systematically and differentially reinforce successive...
TRANSCRIPT
What is Shaping?A process where you systematically and
differentially reinforce successive approximations to a desired behavior
Used to help learners acquire new behaviors
Differential ReinforcementSome members of a response class are
reinforced (responses that are successively closer to the terminal behavior)
Other members of that response class are not reinforced (responses that are not closer to the terminal behavior)
Response DifferentiationInvolves two components:
Differentially reinforce behaviors that resemble the terminal behavior
Carefully changing the criterion for reinforcement
ResultIncrease in behaviors successively closer to
terminal behaviorDecrease in behaviors that are not
successively closer to terminal behavior
SD
Tap on faucet
marked with blue dot or letter “C”
Response
Walk to sink and look at it
SR+
Cold water presented
Walking to sink and looking at it maintains
EO
Deprived of water for a long period
of time
Assume we want to teach a child to turn on the cold water tap in order to get a drink of water.
Assume the child already walks to sink and looks at it when he/she is thirsty.
Shaping might proceed like this:
Response already in repertoire
Cooper, Heron, and HewardApplied Behavior Analysis, Second Edition
Copyright © 2008 by Pearson Education, Inc.All rights reserved
SD
Tap on faucet
marked with blue dot or letter “C”
Response
Walk to sink and look at it
SO
Cold water withheld
Walking to sink and looking at it when deprived of water decreases
EO
Deprived of water for a long period
of time
Shaping step 1:
SD
Tap on faucet
marked with blue dot or letter “C”
Response
Point to tap
SR+
Cold water presented
Pointing to tap when deprived of water increases
EO
Deprived of water for a long period
of time
SD
Tap on faucet
marked with blue dot or letter “C”
Response
Point to tap
SO
Cold water withheld
Pointing to tap when deprived of water decreases
EO
Deprived of water for a long period
of time
Shaping step 2:
SD
Tap on faucet
marked with blue dot or letter “C”
Response
Touch tap
SR+
Cold water presented
Touching tap when deprived of water increases
EO
Deprived of water for a long period
of time
SD
Tap on faucet
marked with blue dot or letter “C”
Response
Touch tap
SO
Cold water withheld
Touching tap when deprived of water decreases
EO
Deprived of water for a long period
of time
Shaping step 3:
SD
Tap on faucet
marked with blue dot or letter “C”
Response
Grasp tap
SR+
Cold water presented
Grasping tap when deprived of water increases
EO
Deprived of water for a long period
of time
SD
Tap on faucet
marked with blue dot or letter “C”
Response
Grasp tap
SO
Cold water withheld
Grasping tap when deprived of water decreases
EO
Deprived of water for a long period
of time
Shaping step 4:
SD
Tap on faucet
marked with blue dot or letter “C”
Response
Turn tap
SR+
Cold water presented
Turning tap when deprived of water increases
EO
Deprived of water for a long period
of timeTerminal Behavior
Dimensions of Behavior that can be ShapedTopography
Form of the behavior
Frequency Number of responses per unit of time
Latency Time between onset of antecedent stimulus and the occurrence
of the behavior
Duration Total elapsed time for the occurrence of the behavior
Amplitude Magnitude
Guidelines for Implementing ShapingConsider Nature of Behavior to be Learned and
Resources AvailableSelect the Terminal BehaviorDetermine Criteria for SuccessAnalyze the Response ClassEliminate interfering StimuliDeprivation of Reinforcers you want to useIdentify the First Behavior to ReinforceLimit the Number of Approximations at Each
LevelContinue Reinforcement when Terminal
Behavior is Achieved
Consider Nature of Behavior to be Learned and Resources Available
How far away is current performance from terminal behavior? This might influence how long shaping will take
What is the availability of staff and other resources? Remember, this is a labor intensive procedure
Select the Terminal BehaviorThe ultimate criterion for selecting a
behavior for change:How will the behavior change contribute to
the learner’s independence in gaining reinforcement?
Define the terminal behavior preciselyThen you’ll know when the behavior has
occurred
Determine Criteria for Success How accurate, fast, long, or intensely should
the behavior be performed? Under what conditions should it be performed?
Establish norms by Consulting literature Observing similar peer group
Analyze the Response ClassIdentify the approximations that might be
emitted during training BEFORE TRAINNG BEGINSTrainer is in a better position to “stay ahead
of his/her subject”Can be done by:
Consulting experts in the fieldUse published literatureUse videotape of peers to analyze
components of a behaviorPerform the target behavior yourself
LIST THEM IN ORDER
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Key to Shaping - DeprivationIf possible, deprive the organism of what you
want to reinforce it with.
Animals with food. Deprive to 80% of its body weight.
Deprive kid of reinforcer you want to use.
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KidsFood
Chocolate Chip Cookies (ccc’s)M & Ms
TokensMoney
Identify the First Behavior to Reinforce Behavior should already occur at some levelBehavior should be a member of the targeted
response class
SpecificsEliminate Interfering Stimuli
Eliminate distractions during trainingProceed in Gradual Stages
Be prepared for decrements in performance when you increase criteria
Limit the Number of Approximations at Each LevelLest the behavior become too firmly
established
Continue Reinforcement When the Terminal Behavior is Achieved
The behavior will be lost if the terminal response is not reinforced
Move to a schedule of reinforcementThin the schedule
Increasing Efficiency of ShapingCombine with other discriminative stimuli
(e.g., a prompt)Verbal cuesPhysical guidanceModels
Positive Aspects of ShapingTeaches new behaviorsIs a positive approach to teachingCan be combined with other procedures,
such as chaining, imitation, etc.
Limitations of ShapingCan be time consumingProgress is not always linear and may be
erraticRequires a skillful trainer, who can
recognize subtly closer approximationsCan be misapplied (problem or harmful
behaviors can be accidentally shaped)
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Reverse ShapingIs different from Regular Shaping Start at the end response, then reinforce it.
Then two steps before you reinforce it,
Then three steps, etc.
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ExamplesTeaching a kid to tie their shoes.
SummaryIs an extremely useful techniqueCan be used with a variety of other techniquesCan be used to change behaviorWe use shaping with many behaviors and do not
know itCan be used systematically to manipulate behavior
of others in a variety of situationsWeight control Business relationshipsFamily relationships
Can take longer than other techniques.