Factorial Design

Factorial Design

Benefits

Interaction effects

Generalizability

Testing complex theories

Interpreting Results

Main effects

Interaction effects

Crossover interaction

Spreading interaction

2x2 design

Main effect of IV1

Main effect of IV2

Interaction between IV1 & IV2

Describe what happens to level 1 of IV1 across the levels of IV2

Repeat this for level 2 of IV1

Repeat this for IV2 levels

“The significant main effect was qualified by an interaction…”

Adding Complexity

More levels

More variables

Testing for moderators allows us to test the limits of our data

Single factor exp. can't tell a WHY a relationship exists

2x2x2 design (3-way)

3 Main Effects

3 2-way Interactions

IV1xIV2

IV1xIV3

IV2xIV3

1 3-way Interaction

IV1xIV2xIV3

Detect using marginal means

Detect using difference of the difference

3 Types

Between-Groups

Within-Groups

Mixed