Preference and Reinforcer Assessments Michael F. Dorsey, Ph.D., BCBA

Preference/ Reinforcer Assessments Why are they vital to the success of any behavioral intervention?

Best Review of the Field: Ivancic, M. (2000). Stimulus Preference and Reinforcer Assessment. In Handbook of Applied Behavior Analysis, Austin, J. & Carr, J. (Eds.), Context Press.

Most Common Method of Preference/Reinforcer Assessment Teacher/Parent Selection

Teacher Choice of Potential Reinforcers a.k.a., “Rewards” Consider age, interests, and appetites of individual Consider the behavior you wish to strengthen (reinforcer value needs to match behavior effort) List potential reinforcers Do teachers choose effective reinforcers?

What research says about teacher choice: Green et al, (1991) found caregiver opinions of preferences did not coincide with student preferences obtained during a choice assessment. Does this matter? “Reward” vs. “Reinforcer”

Preference/ Reinforcer Assessment What is the difference between a preference assessment and a reinforcer assessment? Choice versus function Only reinforcer assessment measures effectiveness!!!

Preference Assessment A large number of stimuli are evaluated to identify preferred stimuli (Piazza, et al., 1996) Purpose is to identify potential reinforcers Does not evaluate the reinforcing effects of the stimuli

Purpose of Preference Assessment Piazza, Fisher, Hagopian, Bowman & Toole (1996) found that high-preference stimuli were very likely to be effective reinforcers, but low function stimuli do not function as reinforcers.

Methods for completing a preference assessment: Self-report (Who? How?) Interview/ Informant Report – Structured or semi-structured interview – Checklist or rating scale Direct observation – Free Operant Direct testing

Preference Assessments Interview or questionnaire – Advantage: Simplicity – Disadvantage: Subjective (based on opinion), unreliable Observation of daily activities (preferences) – Advantage: Objective (based on direct observation) – Disadvantage: Time consuming (except Free Operant), limited access to stimuli Systematic preference assessment – Advantage: Objective, accommodates a wide range of stimuli – Disadvantage: Time consuming

Interviews or Questionnaires

The Person’s Choice Matters!

Methods: Self-Report Involves asking a person to report on items of preference Usually involves interview, checklists, or rating scales

Informant Report Involves interviewing or gathering information via rating scale or checklist from a person familiar with the individual being assessed

Which to Use: Does it Matter? Yes, Generally Self-Report is more Reliable than Parent/Teacher Interviews

Forms to Use for Interviews/ Self-Reports 1.Reinforcer Assessment for Individuals With Severe Disabilities; 2.Description of Potentially Reinforcing Events; 3.Psychiatric Reinforcement Survey Schedule (PRESS); 4.Leisure Item Preference Assessment;

Similar Results re: Tasks Being Reinforced Vaughn & Horner (1997) examined levels of problem behavior on preferred v. non-preferred tasks AND when each task was chosen by teacher v. student; List of preferred v. non-preferred tasks gathered by interview/ observation; Results showed allowing students to choose between pairs of lower preference tasks resulted in lower rates of behavior;

Systematic Preference Assessments

Stimulus Preference Methodologies Study_______Stimulus PresentationResponse Measure Pace et al. (1985)Single, trials% Approach Fisher et al. (1992)Paired, trials% Selection DeLeon & Iwata (1996)Grouped, trials% Selection Roane et al. (1998)Grouped, free operantDuration of engagement DeLeon et al. (1999)Single, trialsDuration of engagement

Direct observation of approach (Pace, et al., 1985) Direct observation in the individual’s natural settings Items present during free play; data recorded on approach to items, self-selection, and duration of use. Arrangements of items

Choice Assessment Initially described by Fisher (1992) Each stimuli presented/ paired with every other stimulus, placed.7 meter apart and.7 m in front of the child An instruction is given to “pick one only” Client approach = 5 seconds of access to choice; simultaneous approach blocked, no response = sampling of each

Choice Assessment: In comparison to single-choice presentation, paired-choice presentation more reliably identifies reinforcers (Fisher, et al., 1992).

Verbal v. Tangible Choice Cohen-Almeida, Graff, & Ahearn (2000) compared tangible presentation of objects with verbal presentation. Assessment using verbal presentation completed in less time Assessment using verbal and tangible presentations achieved comparable results in 4 of 6 individuals

Verbal v. Pictorial Choice Northup et al., (1996) confirmed that verbal choices were as effective as pictorial choices in a choice assessment Also confirmed that survey was less likely to correspond to the results of a reinforcer assessment than choice-based assessments

Ambiguous Preference Assessment Individual may not make any selection: – if none of the items are preferred – if choice-making skills lacking – if several of the items are highly preferred and compete with each other; switches across trials can become ambiguous

What to do… Present items singularly (although this method is less reliable) Do duration based assessment with single items (DeLeon, 1999) – Present items alone – Measure duration subject manipulates items

Free Operant Roane, Vollmer, Ringdahl, & Marcus (1998) Stimulus Preference Assessment – participates had noncontingent access to an array of stimuli and could interact with any of the stimuli during 5-min sessions – object manipulation was recorded using a 10 s partial-interval recording procedure

Free Operant (cont.) Reinforcer Assessment revealed that those items chosen as preferred in the free-operant assessment functioned as reinforcers for a simple operant response

Free Operant (cont.) Advantages - Time efficient - Reduced behavior problems Disadvantages – False negatives – Does not produce rank

Reinforcer Assessments

Reinforcer Assessment The evaluation of a small number of stimuli (highly preferred stimuli) to determine the reinforcing effects of the stimuli Stimuli presented contingently for desired behavior (a multi-element design)

Reinforcer Sampling Ayllon & Azrin (1968) described a procedure called reinforcer sampling, designed to increase the frequency of using potential reinforcers. Involved forced engagement for brief periods of time Increased # and duration of use of the potential reinforcers available

More on Reinforcer Assessment/Sampling Smith, et al., (1995) compared reinforcer sampling to teacher choice (from previously determined preferences) at the start of training sessions and found little to no difference in stimuli were selected by subjects rather than experimenters.