Single-Subject Research & ABA Concepts

Single-Subject Research

Research repeatedly measuring individual behavior across conditions where the subject serves as their own control.

Dynamic Behavior

Behavior that changes over time and varies depending on environmental conditions.

Continuous Behavior

Behavior that is constantly occurring and measured repeatedly over time.

Determined Behavior

Behavior occurring in relation to identifiable variables rather than randomly.

Description

Observation and description of behavior telling what is happening.

Prediction

Consistent covariation of two events allowing one to predict the other without establishing causation.

Control

Manipulating one variable to reliably change another; the highest level of scientific understanding.

Correlation

Systematic covariation of two events allowing prediction but not proving causation.

Independent Variable (IV)

The environmental variable or intervention manipulated by the researcher.

Dependent Variable (DV)

The target behavior measured to determine if it changes due to the IV.

Functional Relation

Reliable changes in the DV produced by changes in the IV, proving causation.

Experimental Control

Predictable behavior change produced by systematically manipulating an IV.

Extraneous Variable

Any variable other than the IV that could influence the DV.

Confounding Variable

An uncontrolled variable changing with the IV that provides an alternate explanation for behavior change.

Internal Validity

Degree to which behavior change is confidently attributed to the IV rather than other variables.

External Validity

Degree to which findings generalize across other people, settings, or behaviors.

Baseline

Measurement of behavior without the IV, labeled A, establishing current behavior patterns.

Intervention Phase

The phase in which the IV is introduced, usually labeled B.

Follow-Up

Measurement after intervention to see if behavior change maintains over time.

Stable Baseline

Baseline with minimal variability or trend, making future behavior predictable.

Variable Baseline

Baseline with considerable changes across observations, making prediction difficult.

Practice Effect

Behavior improves due to repeated exposure during measurement rather than intervention.

Prediction (Baseline Logic)

Expected future level of behavior if environmental conditions remain unchanged.

Verification

Demonstrating that the original baseline prediction was correct.

Replication

Repeating IV manipulation to obtain similar behavior change and strengthen functional relation evidence.

Steady-State Responding

Relatively little variation in behavior over time under consistent conditions.

Steady-State Strategy

Continuing a condition until responding is stable before changing experimental conditions.

A-B Design

A single baseline and intervention phase; weak for proving functional relations.

Affirmation of the Consequent

Assuming an intervention caused behavior change simply because behavior changed after its introduction.

X-Y / Line Graph

Common graph showing behavior across time and experimental conditions.

Y-Axis

Vertical axis showing the dependent variable or target behavior.

X-Axis

Horizontal axis showing sessions, observations, days, or time.

Data Point

A single measurement of target behavior plotted on a graph.

Data Path

Line connecting consecutive data points within an experimental condition.

Solid Vertical Phase-Line

Indicates a major change to a new experimental condition.

Dashed Vertical Phase-Line

Indicates a minor modification within the same intervention.

Legend

Explains symbols, abbreviations, or data paths on a graph.

Behavioral Assessment

Process of identifying, defining, measuring, and evaluating behavior and intervention effects.

Indirect Assessment

Information gathered without direct observation, such as interviews or rating scales.

Direct Assessment

Behavior is directly observed and recorded as it occurs.

ABC Recording

Recording Antecedent, Behavior, and Consequence to examine immediate surrounding events.

Antecedent

Environmental event occurring immediately before a behavior.

Consequence

Environmental event occurring immediately after a behavior.

Reactivity

Behavior changes because the person knows they are being observed.

Ecological Assessment

Examines broader environmental variables affecting behavior like settings and routines.

Target Behavior

Specific observable and measurable behavior selected for assessment or change.

Behavioral Cusp

Behavior change giving access to new environments, reinforcers, or learning opportunities.

Pivotal Behavior

Behavior that, when changed, produces improvements in other untrained behaviors.

Operational Definition

Objective, clear, and complete description of the target behavior.

Topography-Based Definition

Defines behavior by its physical form or what it looks like.

Function-Based Definition

Defines behavior by its effect on the environment.

Outcome Criterion

Predetermined performance level used to judge meaningful behavior change.

Repeatability

Property where behavior can occur repeatedly and be counted.

Temporal Extent

Property where behavior occurs for an amount of time, measured by duration.

Temporal Locus

Property where behavior occurs at a specific point in time relative to other events.

Count/Frequency

The number of times a behavior occurs.

Rate

Number of responses per unit of time (Count ÷ time).

Duration

The amount of time a behavior lasts.

Latency

Time between a stimulus and the beginning of a response.

Interresponse Time (IRT)

Amount of time between two consecutive responses.

Trials-to-Criterion

Number of response opportunities required to reach a performance criterion.

Permanent Product

Measurement using the lasting physical result produced by behavior.

Continuous Measurement

Attempts to measure every occurrence of behavior during an observation period.

Discontinuous Measurement

Samples behavior rather than recording every occurrence to provide an estimate.

Whole-Interval Recording

Scores behavior only if it occurs for the entire interval; underestimates duration.

Partial-Interval Recording

Scores behavior if it occurs during any part of the interval; overestimates duration.

Momentary Time Sampling

Records behavior only if occurring at a specific moment at the end of the interval.

Validity of Measurement

Degree to which measurement actually measures the intended behavior dimension.

Accuracy of Measurement

Degree to which observed values match the true value of behavior.

Reliability of Measurement

Degree to which measurement produces consistent results across repeated uses.

Observer Drift

Observer gradually changes how they apply behavioral definitions over time.

Interobserver Agreement (IOA)

Degree to which two or more independent observers agree when measuring behavior.

Total Count IOA

Smaller count divided by larger count multiplied by 100.

Scored-Interval IOA

IOA focusing on intervals where behavior was scored, useful for low-rate behavior.

Unscored-Interval IOA

IOA focusing on intervals where behavior was not scored, useful for high-rate behavior.

History Threat

Outside event occurring during a study that could explain behavior change.

Maturation Threat

Natural changes over time like development or fatigue affecting behavior.

Treatment Integrity

Degree to which an intervention is implemented correctly and consistently as planned.

Applied Dimension (ABA)

Focuses on behavior that is socially important.

Behavioral Dimension (ABA)

Focuses on observable and measurable behavior.

Analytic Dimension (ABA)

Demonstrates that the intervention is responsible for behavior change.

Technological Dimension (ABA)

Procedures are described clearly enough for replication by others.

Conceptually Systematic (ABA)

Procedures are connected to established behavioral principles.

Effective Dimension (ABA)

Behavior change is large enough to be practically meaningful.

Generality Dimension (ABA)

Behavior change lasts over time and occurs across other settings or behaviors.