Experiments With More Than One IV (Week 12)

Question 1

What are main effects?

What are interaction effects?

Answer 1

Main effects: observing a difference (or no difference) between the levels of an IV
Interaction effects: determining whether the difference between levels of one IV depend on the level of another IV

Question 2

What is a 2x2 factorial design?

Answer 2

Participants get different combinations of manipulated IV

2 (variable) x 2 (stimulus type) - randomly assign participants to four groups

Question 3

What were the results of the head tilt study?

Answer 3

The effect of head tilt on dominance depends on whether people can see the other person’s eyes
With eyes - downward head tilt increased dominance
Without eyes - no effect

Question 4

How do you calculate main effects? - draw this if you need 2

Answer 4

Find cross section averages (Horizontal) - subtract

Find other averages (Vertical) - subtract

Question 5

How do you calculate interaction effects?

Answer 5

Minus averages from each column (vertically), then subtract the products

Question 6

“There was a Bridge X Gender BLANK. The effect of being on the bridge on attractiveness ratings was stronger when the researcher was a female.”

Answer 6

Interaction effect

Question 7

“There was a BLANK of Bridge condition. Participants in the bridge condition rated the researcher as more attractive by 0.5 points. There was also a BLANK of Gender. Participants rated females as more attractive by 0.7 points”

Answer 7

Main effect

Question 8

What is a within-groups factorial design?

Answer 8

All participants complete all combinations of the IVs

Question 9

What is a mixed factorial design?

Answer 9

All participants complete each level of one IV but different levels of the other IV