lecture 13

Question 1

factorial designs

Answer 1

• address research questions involving multiple “independent” variables that potentially work together
• can include independent variables and or participant variables = called factors
• simplest form is a 2X2 factorial design
  ex) factor A= gender, factor B = turn taking hints

Question 2

2X2 factorial design example

Answer 2

• two levels of factor A
  ex) gender: men and women
• two levels of factor B
  ex) implicit turn taking hints: provided or not
• dependent variable
  ex) # of conservation “switches”

Question 3

2X3 factorial design

Answer 3

• could have two independent variables with more than two levels
• each level of factor A has three levels of factor B
  ex) type of phobia (2) and type of treatment (3)

Question 4

2X2X2 factorial design

Answer 4

• could have more than two independent variables, with two or more levels each
• each level of factor A has two levels of factor B
• at each level of factor A at each level of factor B also has two levels of factor C

Question 5

main effects

Answer 5

• the overall effect of each factor on the dependent variable
• differences between means on each individual factor
• we often say collapsing across the other factor
  ex) gender and hit chat

Question 6

interactions

Answer 6

• the influence of one factor depends upon the level of the second factor
• we often say main effects are qualified by an interaction
  ex) bar graphs
  ex) line graphs- are lines parallel/do they cross

Question 7

factorial designs: between subjects

Answer 7

• between-subjects factorial designs
• all factors/IV’s in the design are between subjects
• often participant variables- age and gender
• sometimes used to avoid variability issues
  ex) experimenter

Question 8

factorial designs: with-in subjects

Answer 8

• with-in subjects factorial designs
• all factors/ IV’s are with-in subjects
  ex) type of music and type of stimulus
• same benefits as less complicated designs
• 10 participants per condition = 10 participants

Question 9

factorial designs: mixed methods

Answer 9

• some factors are between subjects and some with-in subjects
  ex) music and studying = can deal with some order effects

Question 10

quasi experimental as factorial designs

Answer 10

• many quasi-experimental strategies are factorial designs
• pre test post test non equivalent control group is 2X2 factorial design!
• time series designs are also factorial designs

Question 11

factorial designs-hypotheses

Answer 11

-what are the null and alternative hypotheses?
-there are multiple hypotheses, one for each potential effect
ex) 2X2 factorial design
Hypothesis 1:
Ho: No main effect of A
H1: Main effect of A

Question 12

statistical analysis

Answer 12

• Unlike a one-way ANOVA, which includes only one factor, factorial ANOVAS have multiple effects to be tested statistically
• main effects of each factor
• interactions