Unit 9

Question 1

What are three reasons for using a factorial research design

Answer 1

In factorial research design you want to examine the effect of two or more variables in a single experiment.

One reason is efficiency: as long as you were designing an experiment, building another independent variable into the design may not require much additional effort

You might have more than one alternative hypothesis to rule out

To reveal interactions among variables

Question 2

How many cells/combinations are there in a 2 x 3 x 4 factorial design?

Answer 2

24 combinations

Question 3

In a factorial experiment, the effect of one independent variable, averaged over all levels of another independent variable.

Answer 3

Main effect

A factorial design with two independent variables is able to have two possible main effects

Question 4

When effective one independent variable depends on the level of another independent variable

Answer 4

Interaction

Question 5

How can one tell graphically if there is an interaction between two variables?

Answer 5

If the graphical representation of a factorial experiment shows curves that are not parallel, there is an interaction between the variables. If the lines are parallel, there is no interaction

Question 6

Is it possible to have an interaction if one or the other independent variable has no main effect, or even if neither independent variable has a main effect?

Answer 6

Yes

Question 7

Interaction in which the two independent variables tend to reverse each other’s effects

Answer 7

Antagonistic interaction

Question 8

Interaction in which the two independent variables reinforce each other’s effects

Answer 8

Synergistic interaction

Question 9

Interaction in which one variable has a smaller effect when paired with higher levels of the second variable

Answer 9

Ceiling-effect interaction

Question 10

What are the three types of interactions in psychological research in factorial design?

Answer 10

Antagonist interaction, synergistic interaction, ceiling-effect interaction

Question 11

Factorial design that has at least one within-subjects variable and at least one between-subjects variable

Answer 11

A mixed factorial design

Question 12

Research design that involves all combinations of at least two values of two or more independent variables

Answer 12

Factorial design