Chapters 11 & 12 - Within-Subjects & Small-N Designs

what is another name for a within-subjects design

a repeated-measures design

What is the main disadvantage of a within-subjects design?

Participants experience multiple conditions, which can create order effects and carryover effects

What is progressive error (order effect)?

Changes in behavior caused by experiencing multiple treatment conditions.
Ex: fatigue.

What are the two major types of progressive error?

Practice/learning effects and fatigue effects.

What is a carryover effect?

When a previous treatment affects performance in a later treatment.
Ex: Drug A's effects continue when Drug B is given

What are four sources of carryover effects?

Habituation, sensitization, contrast, and adaptation

What is subject attrition?

When participants leave or drop out of an experiment.

What is counterbalancing?

Varying the order of treatments across participants to control order effects

What is complete counterbalancing?

Using every possible treatment order an equal number of times.
Ex: 2 treatments, AB and BA

What is a disadvantage of complete counterbalancing?

The number of possible orders increases rapidly as treatments increase, requiring many participants

What is partial counterbalancing?

Using a subset of all possible treatment orders while trying to balance treatment positions

ex: Use AB, BA, and AC instead of every possible order.

When is randomized partial counterbalancing useful?

When complete counterbalancing is impractical because of limited time or participants.

What is a Latin Square design?

A counterbalancing method where each treatment appears once in each position

ex: Each treatment appears once in each position.

How can researchers minimize carryover effects?

Use pre-training, practice sessions, or rest periods between treatments.

When is a within-subjects design especially useful?

When participant differences affect the DV or when participants are limited

What is an advantage of a mixed design?

it can handle variables that cannot be manipulated within participants because of irreversible or carryover effects.

What is a disadvantage of a mixed design?

It is more complex and requires more participants than a completely within-subjects design.

Why are small-N designs useful?

They allow researchers to closely examine individual behavior and can reveal effects that group averages might hide.

What is a single-participant baseline design?

A design where behavior is measured during baseline and treatment phases to determine whether the treatment changes behavior.

What is the baseline phase (A)?

The phase where behavior is measured before treatment to establish a starting point.

What is the intervention phase (B)?

The phase where the treatment/IV is introduced and behavior is measured.

What is a reversal strategy?

Returning to the original baseline condition after treatment to see whether behavior returns toward baseline.
Ex: A → B → A → B

What is intrasubject replication?

Repeating treatment phases with the same participant to establish reliability of the effect.

What is intersubject replication?

Repeating the effect across multiple participants to determine whether the finding generalizes across people.

What is a multiple-baseline design?

A design that uses multiple behaviors, each with its own baseline, when the treatment produces an irreversible change.
Ex: Treating smoking first, then coffee drinking