Within-Participants ANOVA

Question 1

What is the main feature in a within-participants ANOVA?

Answer 1

Each participant serves in each level of each treatment

Question 2

What is error based on in within-participants ANOVA?

Answer 2

The interaction between TR and participants
The changes in the effects of a factor across participants

Question 3

How is total variance partitioned in a within-participants ANOVA?

Answer 3

1. Between - participants variance
2. Within - participants variance

Question 4

How is within - participants variance partitioned in a one- way within - participants ANOVA?

Answer 4

1. Between treatments
2. Error

Question 5

What is the F-ratio for a one-way within - participants ANOVA?

Answer 5

TR/ TR * P

Question 6

What is the structural model of a one-way within-participants ANOVA?

Answer 6

Xij = μ + πi + τj + eij
Grand mean
Variation due to the ith person (μi - μ)
Variation due to the jth treatment (μj - μ)
Error (πτij)

Question 7

What is total variability in a within-participants ANOVA?

Answer 7

Deviation of each observation from the grand mean

Question 8

What is variability due to factor in a within-participants ANOVA?

Answer 8

Deviation of factor group means from the grand mean

Question 9

What is variability due to participants in a within-participants ANOVA?

Answer 9

Deviation of each participant’s mean from the grand mean

Question 10

What is variability due to error in a within-participants ANOVA?

Answer 10

Changes in the effect of a factor across participants (TR * P interaction)

Question 11

What is df total in a within- participants ANOVA?

Answer 11

N - 1
no. of observations - 1

Question 12

What is df participants in a within-participants ANOVA?

Answer 12

n - 1
no. of participants - 1

Question 13

What is df treatment in a within-participants ANOVA?

Answer 13

j - 1
no. of levels - 1

Question 14

What is df error in a within-participants ANOVA?

Answer 14

(n - 1)(j - 1)

Question 15

When is the error term different in within-participants ANOVA?

Answer 15

For any follow-up test

Question 16

What kinds of factors does a mixed-model include?

Answer 16

Fixed and random factors

Question 17

What is an example of a random factor?

Answer 17

Participants

Question 18

What is a fixed factor?

Answer 18

A factor in which the levels are chosen

Question 19

What is a random factor?

Answer 19

A factor in which levels are random

Question 20

What are the three assumptions of mixed-model approaches?

Answer 20

1. Random sampling
2. Assumption of normality
3. Compound symmetry

Question 21

What is compound symmetry

Answer 21

Assuming that the variances and covariances between levels in a repeated-measures factor are similar

Question 22

What is the assumption of compound symmetry replaced with?

Answer 22

Mauchely’s test of sphericity

Question 23

When does sphericity matter?

Answer 23

In a within-participant design with more than 2 levels

Question 24

What happens when sphericity is violated?

Answer 24

Increased Type 1 error - critical values are too small

Question 25

How is sphericity adjusted for?

Answer 25

Through epsilon adjustments

Question 26

How does epsilon adjust critical values?

Answer 26

Through changing the degrees of freedom

Question 27

What does a value of epsilon close to 0 mean?

Answer 27

There was a big adjustment to the critical value

Question 28

What are advantages of within-participants designs?

Answer 28

1. More efficient
2. More sensitive (greater power)