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					Choice and Matching


     Chapter 10


                                1
     Steven I. Dworkin, Ph.D.
                   Choice
• Can you think of a situation or behavior that
  does not involve choice?




                                              2
                  Steven I. Dworkin, Ph.D.
         Choice and Matching
• Concurrent schedule of reinforcement
  – Simultaneous presentation of two or more
    independent schedules, each of which leads to a
    reinforcer.
• Conc
  – VR 20        VR 50
  – VI 30        VI 60

                                                  3
                  Steven I. Dworkin, Ph.D.
           The Matching Law
• Hernstein’s 1961
• Concurrent VI
  schedules (eg. VI 135”
  VI 270” – 13 versus
  27 reinforcers/hr)




                                              4
                   Steven I. Dworkin, Ph.D.
          The Matching Law
• Proportion of           • Ra/Ra+Rb =
  responses emitted on a    SRa/SRa+SRb
  particular schedule
  matches the proportion
  of reinforcers obtained
  on that schedule.




                                            5
                 Steven I. Dworkin, Ph.D.
              Matching Law
•   Data from pigeon on a conc VI 30 VI 60
•   Reinforcers VI 30 – 119, VI 60 – 58
•   Responses VI 30 – 2800, VI 60 – 1450
•   Proportion of reinforcers -119/177 = .67
•   Proportion of responses – 2800/4250 = .66



                                                6
                   Steven I. Dworkin, Ph.D.
                 Matching
• Not just in the laboratory
• Not just rats and pigeons




                                             7
                  Steven I. Dworkin, Ph.D.
    Deviations from Matching
• Undermatching – proportion of responses
  on the richer alternative versus poorer
  alternative is less different then those
  predicted from matching (less different)
• Little cost for switching from one
  alternative to another.


                                             8
                 Steven I. Dworkin, Ph.D.
     Deviations from Matching
• Overmatching – proportion of responses on
  the richer versus poorer of two alternatives
  is more different than would be predicted by
  matching (overmatching more different)
• Cost to move is high



                                             9
                 Steven I. Dworkin, Ph.D.
     Deviations from Matching
• Bias – one alternative attracts a higher
  proportion of responses than would be
  predicted by matching, regardless of
  whether that alternative is the richer or
  poorer of the two alternatives.




                                              10
                  Steven I. Dworkin, Ph.D.
Deviations from Matching




                                   11
        Steven I. Dworkin, Ph.D.
        Quality and Amount
• Matching holds




                                              12
                   Steven I. Dworkin, Ph.D.
 Application to Single Schedules
• As relative reinforcement for operant
  response increases responding will increase
• Context is important
  – Outdated magazines in doctors office
  – Covering JEABs when graduate applications
    are due



                                                13
                 Steven I. Dworkin, Ph.D.
               Melioration
• To make better
• The distribution of behavior in a choice
  situation shifts toward those alternatives
  that have a higher value regardless of the
  effect on the overall amount of
  reinforcement


                                               14
                  Steven I. Dworkin, Ph.D.
    Problems with Melioration
• Tendency towards richer alternatives can
  result in reduction in obtained
  reinforcements
• VR 100 VI 30
  – Allocation of study time to different courses




                                                    15
                   Steven I. Dworkin, Ph.D.
    Problems with Melioration
• Over indulgence in a highly reinforcing
  alternative can often result in long-term
  habituation to that alternative, thus reducing
  its value as a reinforcer.
  – Too much of a good thing……
  – Be careful of what you wish for….



                                               16
                  Steven I. Dworkin, Ph.D.
    Problems with Melioration
• Often the result of behavior being too
  strongly governed by immediate versus
  delayed consequences.




                                            17
                 Steven I. Dworkin, Ph.D.
        Optimization Theory
• Make decisions that maximize satisfaction
• Matching law –description
• Optimization theory – explanation
• Matching occurs when it is optimal thing to
  do
• Concurrent VIs matching maximizes the
  rate of reinforcement
                                            18
                 Steven I. Dworkin, Ph.D.
  Optimization versus Matching
• Mazur 1981
   – Concurrent chained
     schedules
   – Matching over
     optimization
• Concurrent VI VR
   – Matching
• Other studies
  optimization
                                                19
                     Steven I. Dworkin, Ph.D.
 Molar versus Molecular Control
• Context
• History
• Bias




                                       20
            Steven I. Dworkin, Ph.D.
  Momentary Maximization Theory
• Selection of alternative with highest value at the moment
   – Size and quality of reinforcer
   – State of deprivation
• Momentary best choice not always best in long run (self-
  control)
• Order in moment to moment patterns?
• Gambling experiment
• Data suggest absence of momentary maximization if
  number of responses considered
• Maybe maximization if time considered

                                                              21
                          Steven I. Dworkin, Ph.D.
           Delay Reduction
• Choice related to reduction in delay to
  reinforcement




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                  Steven I. Dworkin, Ph.D.
        Self-Control Choices
• Small immediate reinforcer versus delayed
  larger reinforcer.
  – Impulsivity versus self-control




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                   Steven I. Dworkin, Ph.D.
                  Self-Control
• Controlling Responses (Skinner)
       • Controlled response
  –   Physical restraint
  –   Deprivation satiation
  –   Doing something else
  –   Self-reinforcement and self-punishment



                                                 24
                      Steven I. Dworkin, Ph.D.
                     Self-Control
• Temporal Issue
      – Lack of self-control arises from the fact that our
        behavior is more heavily influenced by immediate
        consequences as opposed to delayed consequences.

                      Immediate Consequence          Delayed Consequence


quitting              withdrawal                     Improved health


smoking               Nicotine high                  Deterioration of health




                                                                               25
                          Steven I. Dworkin, Ph.D.
               Self-Control
• Self-control – preference for larger later
  reward
• Impulsiveness – preference for smaller
  sooner reward




                                               26
                  Steven I. Dworkin, Ph.D.
        Anslie-Rachlin Model
• Preference for self-control versus impulsive
  choice shifts over time.
• Value of reward is hyperbolic function of
  delay
  – Value of reward increases more sharply as
    delay decreases and reward becomes more
    imminent.


                                                27
                  Steven I. Dworkin, Ph.D.
                           28
Steven I. Dworkin, Ph.D.
         Which do you prefer
• $500 now or $1,000 in two years
• $500 in four years or $2,000 in six years




                                              29
                 Steven I. Dworkin, Ph.D.
     Changing the Shape of Delay
•   Biological factors
•   Behavioral disorders
•   Age
•   Drugs
•   History of delayed rewards
•   Availability of other reinforcers
•   Chaining or setting up subgoals
                                               30
                    Steven I. Dworkin, Ph.D.
      Improving Self-Control
• Precommitment
• Self-reinforcement
• Punishment for impulsive option




                                           31
                Steven I. Dworkin, Ph.D.
       Other Choice Situations
• Preference for variability
  – Pigeons - fixed delay has to be 3-4 secs longer
    to be preferred over a variable delay.
  – VR 60 over FR 30




                                                      32
                   Steven I. Dworkin, Ph.D.
  Preference for Variable Delays
• Delay discounting
  – Longer delay less value
    of reinforcer




                                                33
                     Steven I. Dworkin, Ph.D.
     Tragedy of the Commons
• Freedom in a commons brings ruin to all.
• precommitment
• Punishers more immediate reinforcers




                                             34
                 Steven I. Dworkin, Ph.D.

				
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