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Disequilibrium Approaches

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  1. Disequilibrium Approaches A newer model!

  2. Goal of behavior analysis/operant conditioning • Clarify control of human behavior by reinforcement contingencies • many techniques have been developed • used in wide variety of settings • Problem: specifying ahead of time what works: • no a priori way of determining what will be a reinforcer • makes for problems in applied settings • even lab research affected by this • what usually do: reinforcer assessments • time consuming • not very accurate

  3. Successful approach to a priori assessment should satisfy 3 practical requirements Identification of Rs circumstances should involve: • a small number of simple, nonintrusive procedures • must be widely applicable • require no special apparatus • no novel or disruptive stimuli to be introduced • must be accurate and complete • result should be adaptable to variety of situations, rather than limited to small number of stimuli, responses or settings

  4. TransituationalSolution: conceptual Analysis • Meehl, 1950 • simplest method for figuring out what works: use what circumstances have worked in the past • if works in one setting, should work in others • Three important assumptions about reinforcing stimuli and their "setting conditions" • reinforcersand punishers form unique, independent sets of transituationallyeffective stimuli • essential function of the contingency = produce temporally proximate pairings between response and reinforcer • deprivation schedule specifying long-term denial of access to reinforcer= critical setting condition

  5. TransituationalSolution: conceptual Analysis • Problem: • none of these holds up to data • The assumptions are incorrect! • reinforcersand punishers are not mutually exclusive nor are they transituational • eg. Premack:drinking and wheel running could reinforcer each other • applied settings see this all the time • temporal contiguity not sufficient to produce reinforcement: • Premack(1965): pairing wheel running w/drinking had no effect in absence of contingency schedule • appear that contingency is key, not time • long term deprivation not necessary nor sufficient: short term deprivation works

  6. Application problems w/this approach: • STILL is most often used technique • Assessment techniques are intrusive • Not very effective: reinforcers seem to change • Does not account for satiation effects, etc. • Lacks flexibility, accuracy • Ethical questions when using food, certain punishments

  7. Premack's Probability Differential Hypothesis: (Grandma’s Law) • Premack(1959; 1965): distinct improvement over transituational view • schedule in which a higher probability response is contingent upon a lower probability response will result in reinforcement • if you eat your peas (low prob) then you can have chocolate pudding (high prob) • important change in concept of reinforcement in several ways: • reinforcement is related to access to a response • probability of response determined by probability (duration) of that response in FREE BASELINE • shows that transituational situation is special case of probability-differential: • highest probability response contingent upon a lower probability response • as long as is highest probability- should be transituational

  8. Premack's Probability Differential Hypothesis: (Grandma’s Law) • Some problems, however: • incomplete and unclear about several things: • fails to specify conceptual rules for setting values of contingency schedule:- pair 1:1, 5:1 or what? • Unclear about role of reduction in contingent responding relative to baseline that typically accompanies an increase in instrumental responding • Unclear about role of long-term deprivation

  9. Application • Probably most widely used behavioral technique • Popularity due to several desirable characteristics: • procedures for identification are clear, relatively non-disruptive • more accurate than transituational method • allows for far wider choices of Sr's and P's • Problems even in applied arena: • duration of discrete response hard to measure • duration not always a good measure • problem in that must always use higher probability responses as reinforcers • time consuming to measure baselines

  10. Response Deprivation and Disequilibrium Approach • Assumption: reinforcement results from adaptation of motivational processes underlying free baseline responding to the performance constraints imposed by a contingency schedule • What's that? • are constraining behavior that would naturally occur in free baseline to a set contingency schedule • only allowing free baseline behavior to occur at certain levels, rates, times • restrict via a contingency schedule • really looking at molar equilibrium theory: • free baseline = equilibrium state • disrupt this equilibrium state via a contingency schedule • assumes assessment of free-baseline of instrumental and contingent responding before imposition of contingency schedule

  11. Response Deprivation and Disequilibrium Approach • does NOT view baseline as stable hierarchy of reinforcement value: • estimate of relative motivation underlying different responses • that is- can change from situation to situation • Idea that just must disrupt baseline ratio and you create behavioral effects • by imposing different contingencies- can create reinforcement and punishment conditions: • response deficit: reinforcement • response excess: punishment

  12. Response deficits and satiation • Response deficit: I/C >Oi/Oc • If individual maintains instrumental responding at baseline level, would engage in less of baseline level of contingent responding • thus: if I continue to eat my baseline level of peas, I would engage in less chocolate pudding eating (than baseline) • Response excess: I/C < Oi/Oc • Is the individual maintains instrumental responding at baseline level, would engage in too much of baseline level of contingent responding • if I hit my sister at baseline levels, I would engage in/receive more spankings than I engaged in/received during baseline

  13. Why an improvement? • improvement for several reasons: • specifies rules for setting terms of schedule: • I/C > Oi/Oc for reinforcement effects • I/C < Oi/Oc for punishment effects • I = instrumental response • C = contingent response • Oi = baseline rate of instrumental response • Oc = baseline rate of contingent response • no limitations on units for measuring baseline behaviors, as long as keep same in contingency setting and ratio • sets NO restrictions on what can be a reinforcer or a punisher • note: lower probability response can reinforcer higher probability response, as long as setting conditions are met • shows that long term denial is NOT necessary: • Critical: allows for deprivation or disequilibrium within a session • long term denial is special case of this

  14. Applications • Several desireable reasons for using: • procedures specific • relatively non-disruptive • more accurate • allows incredible flexibility- no set reinforcers or punishers • Examples: Konarski (1980): • grade school kids • free baseline of coloring or working simple arithmetic problems • Konarski(1985): EMH classroom • retarded children • working arithmetic problems and writing • incidental teaching • behavior contracting: Dougher study (1983) • good behavior game • overcorrection: punishment technique

  15. Incidental teaching and the Minimum bliss point model Farmer-Dougan, 1998 • Bitonic relationship between rate of reinforcement imposed by a schedule and strength of reinforcement effect • Response rate first increase then decrease as reinforcer rate increases • When schedule provides very high rate of reinforcement (disrupts disequilibrium only slightly) – little change in instrumental responding • When schedule provides very low rate of reinforcement (disrupts disequilibrium to high degree), little net reinforcement effect • Thus, extreme rates of reinforcement should be less effective than moderate rates

  16. Can mathematically predict reinforcement effects! • Simple FR schedule: according to minimum distance models, R rate that produced by ratio schedule is equal to: • R1 = predicted rate of response • Oi is rate of unconstrained instrumental response • Oc is rate of unconstrained contingent response • K is number of units reinforcement/response (inverse of FR requirement)

  17. Incidental teaching • Accurately IDs reinforcers and increases generalization and maintenance via use of naturalistic teaching • Involves capturing a teaching moment (Hart and Risley, 1980) • Subject initiates (verbally/physically) toward an item or activity • Teacher immediately imposes contingency such that access to the item/activity is blocked until the contingent response is emitted • Immediate assessment of baseline and immediate imposition of momentary disequilibrium • Question: how often to disrupt? • Minimum bliss models suggest that moderate amounts should be better than high interruption or very low interruption

  18. Method • 4 head start preschoolers • Worked 1:1 in workroom at Head Start • Set of toy items for each child, and set of 26 flash cards containing letters A to Z • Task: ID letter expressively to gain access to toy • Manipulated rate of disruption: • Baseline (0) • 25% • 50% • 75% • 100%

  19. Results! • Little academic behavior when did not disrupt ( • surprisingly, there was some • but differed by child • Shows differences in baseline rates • Too much disruption = no academic responding! • Moderate levels worked best!!

  20. Limitations on/Extensions of Disequilibrium approach • not completely accurate • how to measure baseline for individual subjects • time consuming nature of measuring baseline • only takes into account 2 behaviors (I and C), while many more behaviors occur in any contingency setting • Question of time frames: do baselines change w/time? • Does constraining baseline affect or reset baseline?

  21. Conclusions • Strong need to predict reinforcement ahead of time • if can't- not very usable concept • early theories did not do this very well • Reinforcersand punishers aren't things: • no magic wand • reinforcement/punishment effects depend upon extent to which contingency schedule constrains the free distribution of responding