Reinforcement: Part 1

Week 5: Increasing Behavior

Positive Reinforcement

• Delivered Immediately after a behavior• Delivered contingent upon a behavior• Increases probability of future behavior

Potential Rule Governed Behavior

• When no immediate consequence• Behavior changes without reinforcement• Large increase in behavior follows one

instance of reinforcement• Rule exists

Some important Points

• We do not reinforce people• Practice is not reinforcement• Feedback is not always reinforcement• Artificial Reinforcement does not mean “fake”

Motivating Operations

• Establishing Operations: Increases temporarily the immediate effectiveness of a reinforcer.– Deprivation

• Abolishing Operations: Decreases temporarily the immediate effectiveness of a reinforcer– Satiation

4 term Contingency

EO A B CNo water Drinking Drink Fluid intake

Fountain

Reinforcement Classification

• Unconditioned– Unlearned– Primary

• Conditioned– Secondary– Learned

Generalized Conditioned Reinforcement

• Neutral Stimulus that is paired with many other reinforcers– The more reinforcers are paired with a neutral

stimulus the more likely the neutral stimulus becomes a GCR

– E.g. money

Premack Principle

• LPR Before access to HPR• Response-Deprivation Hypothesis (Timberlake

& Allison, 1974).– This is an important consideration when

developing treatments.– Don’t just make HPR contingent. – It must be contingent and be deprived relative to

free operant levels!

Identifying Potential Reinforcers

• Stimulus Preference Assessment– Ask People

• Open ended questions• Choice Format• Rank-ordering

– Observe• Contrived• Naturalistic

– Experiment• Single Stimulus• Paired Stimuli• Multiple Stimuli

Identifying Potential Reinforcers Continued

• Reinforcer Assessment– Concurrent Schedule of Reinforcement• May cause premature rejection (preference does not

mean ineffective reinforcer).

– Multiple Schedule Reinforcer Assessment– Progressive-Ratio Schedule Reinforcer Assessment• Increase response effort (schedule) and see how

behavior changes.

Other Methods of Identifying Reinforcers

• ABAB• Non-contingent Reinforcement• Differential Reinforcement

Non-Contingent Reinforcement?

• What is wrong with this term?• Presenting Reinforcement on a time schedule

Tips for Using Reinforcement

• Easily Achieved Initial Criterion• Sufficient Magnitude of Reinforcer• Vary Reinforcer• Direct contingencies when possible• Use prompts with reinforcement• Reinforce each occurrence initially• Use praise/attention with other reinforcers• Gradually increase response-to-reinforcement

delay (some call this fading – it is not – Thinning)

Negative Reinforcement

• Removal of aversive stimulus• Immediately after a behavior• Increases probability of behavior in future

Escape Versus Avoidance

• Escape – Termination• Avoidance – Prevention

Examples?

Schedules of Reinforcement

Fixed Ratio

• Reinforcement delivered after a specific number of target responses are emitted.– Post Reinforcement Pause• Larger the ratio longer the PRP

– DeLuca & Holborn (1990)• Provided FR schedule to pedaling behavior of fat

people. Fat people started pedaling more

Variable Ratio

• Reinforcement provided contingent upon a variable number of responses.

• Strong Consistent Performance• Group Contingencies makes use of VR

Schedules

Fixed Interval

• Reinforcement provided after first response after specified period of time.

• PRP and Scallop Effect• Slow rates of responding

Variable Interval

• Reinforcement provided after first response after variable duration of time elapsed.

• Constant stable rate of responding• Limited Hold: amount of time R+ is available

once interval elapses.

Differential Reinforcement

• DR-Other• DR-Alternate• DR-Icompatiable• DR-Lower Rates• DR-Higher Rates

Compound Schedules of Reinforcement

• Can be:– Successive or simultaneously– With or without discriminative stimuli– Reinforcement for each element or for the

combination of all.

Concurrent Schedules of Reinforcement

• 2 contingencies of reinforcement operating independently and simultaneously– E.g. you can study or go out for the night

• Behaviors are Matched to maximize rates of reinforcement

Discriminative Schedules

• Multiple Schedule (Stimulus discrimination)– Alternating two or more schedules– Uses an S+ to signal each schedule• (e.g. 1 behavior class but two different situations for

two different reinforcement schedules)

• Chained Schedule– Specific order of presentation– Behavior may be different for each schedule– All schedules must be complete for final outcome

Nondiscriminative Schedules

• Mixed Schedules– Same as Mult. But no discriminative stimulus– FR15/FI1 sometimes after FR15 and sometimes

after FI1• Tandem Schedules– Same as chained but no discriminative stimulus– FR 15/FI2 means first instance will be 15 response

and second will be in 2 minutes

Combined Schedules

• Alternative Schedules– Either or Schedule (whichever comes first)

• Conjunctive Schedules– Both Schedules being met before reinforcement is

provided

Matching Law

• Myerson Article