chapter 12

Question 1

What are the two types of interactions? Give an example for each

Answer 1

1. Intuitive interaction or a crossover interaction “It depends”
   Example : People’s liking for ice cream and pancakes depends on the temperature of the food
2. Spreading interaction or a fan interaction “Especially when”
   Example : the rate deliciousness of a sandwich is good with avocado especially when paired with bacon.

Question 2

What is a factorial design?

Answer 2

A factorial design is one in which there are two or more independent variables. These two IV’s are crossed. They are to study manipulated variables or measured variables, and to test for interactions.

Question 3

What is a cell in a factorial design?

Answer 3

A condition in an experiment; in a simple experiment, a cell can represent the level of one independent variable; in a factorial design, a cell represents one of the possible combinations of two independent variables.

Question 4

Give an example of a factorial design and its elements.

Answer 4

Two IVs
1. Driver’s age
2. Use of cell phone
Each of these has 2 levels
1. Younger or older driver
2. Using cell phone while driving or not
This is a 2x2 design

Question 5

What is a main effect?

Answer 5

In a factorial design, the overall effect of one independent variable on the dependent variable, averaging over the levels of the other independent variable.

Question 6

Explain how factorial designs can test limits.

Answer 6

One reason researchers conduct studies with factorial designs is to test whether an independent variable affects different kinds of people, or people in different situations, in the same way.

Question 7

What does it mean when there are parallel lines in a graph for factorial design?

Answer 7

Parallel lines represent NO interaction. For example, in the case of young and old drivers and cell phone use, there are parallel lines (representing age), meaning the effect of talking on a cell phone DOES NOT depend on age

Question 8

True or False : The goal of factorial designs is to test for external validity.

Answer 8

True : When researchers test an independent variable in more than one group at once, they are testing whether the effect generalizes.

Question 9

Give an example of how a factorial design can test theories.

Answer 9

We want to test why drinking alcohol causes aggression.
IV1 : Photo type
IV2 : Word type
DV : Reaction time
Levels :
IV1 : Alcohol photo – plant photo
IV2 : Aggressive – neutral
This is a 2x2 factorial design

Question 10

How many main effects should we look for in a 2x2 factorial design?

Answer 10

There should be 2 main effects.

Question 11

True or False : If the confidence interval does not include 0, it is statistically significant.

Answer 11

True

Question 12

What does it mean to say “there is a difference in differences”?

Answer 12

A difference in differences represents the interactions between two IVs in a factorial design. This interaction effect is the third result in a factorial design.

Question 13

True or False : Interactions are just as important as main effects in factorial designs.

Answer 13

False : Interactions are almost always more important.

Question 14

What is meant by a 4 x 2 factorial design?

Answer 14

There are 2 independent variables, one of them has 4 levels, and the other has 2 levels.

Question 15

What is a mixed factorial design?

Answer 15

In a mixed factorial design, one independent variable is manipulated as independent-groups and the other is manipulated as within-groups

Question 16

Give an example and the information of a 2 X 3 factorial design.

Answer 16

A 2 x 3 design represents 2 independent variables, one of which has 2 levels, the second having 3 levels.
IV1 : Driver age
Levels : Younger drivers – older drivers
IV2 : Cell phone condition
Levels : Hands-free cell phone – handheld cell phone – no phone
There would be 6 cells total because 2 x 3

Question 17

How many main effects are there in a 2 x 3 x 4 design?

Answer 17

There are 3 main effects to test.

Question 18

How many two-way interactions are there in a 2 x 2 x 2 factorial design?

Answer 18

There are 12 – depends on the number of cells.

Question 19

In a 2 x 2 x 2 factorial design, how do we know if there is a three-way interaction in a graph?

Answer 19

There are 2 cases where there is a three-way interaction
1. If one of the interactions shows a cross interaction and the other is a fan interaction.
2. If both interactions are a cross interaction but reversed patterns in the two-way interaction.

Question 20

Give a 3 x 3 x 3 factorial design example.

Answer 20

DV : Fatigue
IV1 : Coffee consumption (no coffee, 1 cup, 10 cups)
IV2 : Smoking (no smoking, 1 cig, 10 cigs)
IV3 : Hours of sleep (no sleep, < 6 hours, 6+ hours)

Question 21

How can we identify factorial designs in popular media articles?

Answer 21

When looking in popular media articles, we will see “it depends” or “only when” to highlight an interaction. We will also look for participants variables (measured variables such as age, gender, ethnicity)