Chapter 11 - Factorial designs

define factorial design

research design which includes two or more factors

interactions are present in factorial designs when _____

the effects of one factor depend on another factor

True or false

factorial designs may feature

1. all between-subjects designs

2. all within-subject designs

3. a mix of both

True

give an example of mixed designs

a study is done with a treatment group and a control group (concurrent with between subjects designs) but each participant is evaluated pre and post treatment (concurrent with within subjects designs)

when computing a two way interaction, we know there is an interaction if _____

the size and direction of the row differences are the same as the corresponding column differences

in factorial designs, each _____ is denoted by a letter and each ______ is represented by a number

• factor

• level of the IV

True or false? a 2×3 design has two factors, the first of which has 2 levels and the second has 3 levels

True

define the interaction effect

Combined effect of factors

True or false? in the following three way interaction between factors a,b,c, the possible pairs are a-b a-c b-c

false, thee way interaction: a-b-c or 3x two way interactions: a-b b-c a-c

how can you identify main effects with a matrix

compare column means together and row means together

how can you identify interactions with a matrix

compare the difference in row means (differences of row means will be different if there is an interaction)

when reporting an interaction, your statement should include the phrase “____”

depends on

what are the 3 types of factorial designs

1. pure (between-subjects) factors

2. within-subjects factors

3. mixed designs

define high order factorial designs

factorial designs with three or more factors

define between-groups factorial designs

Different groups of participants are randomly assigned to each cell of the design

define within groups factorial designs

same group of participants present in all conditions

when individual differences are high, (within-subject factorial designs/ between subjects factorial designs

within-subjects factorial designs

define mixed factorial designs

factorial studies combining both within and between-subject designs characteristics

mixed factorial designs are mostly used when ________ is expected to threaten validity

one factor

in the three factor design for factors a, b, and c, what does the researcher evaluate

1. effects of factors a, b, and c

2. three two-way interactions (a-b b-c a-c)

3. one three-way interaction (a-b-c)

in factorial designs, more than ____ factors should be avoided

3

what are the 2 standard practice steps to statistical analysis of factorial designs

1. computing the mean for each treatment condition (cell)

2. use ANOVA to evaluate the statistical significance of the mean differences