Lecture 4 - Principles of Experimental Designs III

Question 1

What does multiple independent variables (IV) mean?

Answer 1

More than one independent variable

Question 2

What does having multiple IV’s allow?

Answer 2

Allows an interaction

Question 3

What can happen when an interaction occurs?

Answer 3

The relationship between one IV and DV may change as the levels of the other IVs change

Question 4

What is a fully crossed/factorial design?

Answer 4

When you have a number of IVs and you collect data in all combinations of the levels or your IVs

Question 5

What are factors?

Answer 5

The different IVs in a factorial design

Question 6

What are factors?

Answer 6

The different IVs in a factorial design

Question 7

What is a mixed design?

Answer 7

When one IV is within-subjects and one IV is between-subjects

Question 8

What is a main effect?

Answer 8

• Focusing on one IV and ignoring the other one(s)
• There is a main effect for each of the IVs

Question 9

How do you calculate a main effect?

Answer 9

Take the average of each column or row and compare the difference. The larger the difference, the more it is significant and there is a main effect

Question 10

What is an interaction effect?

Answer 10

• The effects of one IV on the DV, taking into sccount the other IV(s) in the study
• There is an interaction for every combination of IVs

Question 11

How do you calculate the interaction effect?

Answer 11

Take the differnce between the cells of interest and compare