Factorial Designs & Interactions Lecture Notes

This set of flashcards covers key concepts from factorial designs and interactions as well as quasi-experimental designs, small-N designs, and aspects of replication and validity in research.

Interaction

An interaction exists when the effect of one independent variable depends on the level of another independent variable.

Factorial Design

A study design that examines the effects of two or more independent variables.

Non-additive Effect

A situation where the combined effect of independent variables is not equal to the sum of their individual effects.

Levels of an Independent Variable

The different conditions or values that an independent variable can take in an experiment.

Main Effects

The direct effects of each independent variable in a factorial study.

Participants per Cell

The number of participants assigned to each condition in a factorial design.

Marginal Means

The average scores for one independent variable, collapsing across the other independent variables.

Interrupted Time-Series Design

A quasi-experimental design that measures a dependent variable multiple times before and after an intervention.

Nonequivalent Control Group Design

A research design that has both a treatment group and a comparison group but lacks random assignment.

Small-N Design

A research design that involves intensive, repeated measurements of a small number of participants.

Direct Replication

Repeating a study using the same methods and procedures as the original.

Conceptual Replication

Testing the same hypothesis using different methods or paradigms.

Meta-analysis

A statistical technique that combines results from multiple studies to estimate an overall effect size.

P-hacking

The practice of manipulating statistical analyses to achieve statistically significant results.

HARKing

Hypothesizing After Results are Known; presenting post-hoc explanations as if they were predicted.

External Validity

The extent to which research findings can be generalized to real-world settings.

Ecological Validity

Another term for external validity, focusing on how findings can apply in real-world environments.

WEIRD

An acronym representing subjects from Western, Educated, Industrialized, Rich, and Democratic cultures, often criticized for limited generalizability.