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Behavioral Assessment. Selection and Definition of Target Behaviors Selection of a Measurement Device Recording behavior (Collection of Data) Assessment of Reliability or IOA (Lecture 6) Selection of Data Display/graphing (Lecture 7). Freedom of Speech?. Behavioral (OP) Definitions.
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Behavioral Assessment • Selection and Definition of Target Behaviors • Selection of a Measurement Device • Recording behavior (Collection of Data) • Assessment of Reliability or IOA (Lecture 6) • Selection of Data Display/graphing (Lecture 7)
Behavioral (OP) Definitions • Walking • Form: Body movement with alternating L/R leg forward • Restriction: Body erect • Restriction: One foot always in contact with ground • Revised form: Body movement with erect torso, with alternating L/R leg forward with one foot always in contact with the ground • Hallucination • Form: Verbal statement (usually of personal experience) • Restriction: Experience or events unlikely to have basis in reality • Revised form: Verbal statement about a personal experience unlikely to have any basis in fact
Characteristics of a Good Measurement System • Objectivity: Response (R) definitions are observable, unambiguous • “Poor self-concept” • Reliability: Instrument produces consistent (repeatable) results • Verbal estimate of amount of time spent running • Validity: Instrument produces accurate representation of events • An 11.5-inch ruler • Sensitivity: Instrument reflects changes in R • Use of an analog watch to time a race
Recording behavior (Data Collection) • Outcome (product): Observable results of R • Process: Observable aspects of ongoing R
Outcome Observation • Advantage: Convenience; does not require presence of observer • Disadvantages: • Some Rs do not always produce the same outcome • Study, athletic practice, amount of time spent working • Some outcomes can be produced by Rs other than the target • Weight loss (from diet, exercise, laxatives)
Process Observation • Advantage: Flexible; can accommodate a wide range of Rs • Disadvantage: Requires system to account for multiple R dimensions • *Topography: Form of R; usually restricted by R definition • Magnitude: Force of R • *Frequency: Number of occurrences of R • *Duration: Amount of time during which R occurs • Latency: Time elapsed from some starting point to R onset • Interresponse time (IRT): Time elapsed between episodes of R
Measuring Ongoing Behavior(Process Observation) • Continuous Recording: Every instance of R is counted • Event recording: Frequency, rate • Duration recording: Duration, latency, IRT • Discontinuous sampling (i.e., interval recording): Only a subset of Rs is counted • Divide session time into equal intervals • Record occurrences of R during an interval • Convert into % of intervals during which R occurred
Sampling Methods • Data Collection Exercises • Videos • In vivo
Interobserver Agreement (Reliability) • Definition: Consistency of an observational code, or the extent to which an observational code produces the same results across samples (subjects, behaviors, time, observers, etc.) • Method for assessment: Collect independent samples of data; compare results to a standard or to each other
Reliability Calculations • Total agreement: Compare overall session values (totals) obtained by two observers • Rel = Smaller / Larger • Interval agreement: Compare individual data entries by two observers and score as agreements or disagreements • Rel = # Agreements / (# Intervals) • Exact agreement: Compare frequencies entered by two observers and score exact agreements • Rel = # Exact agreements / (# Intervals) • Proportional (frequency-within-intervals) agreement: Compare frequencies entered by two observers and score proportional agreements • Rel = ∑ (Smaller/Larger) / # Intervals