Statistics for the Behavioral Sciences by Frederick J. Gravetter, Larry B. Wallnau ISBN 10: 1305504917 ISBN 13: 9781305504912

PROBLEMS 441
PROBLEMS
1. How does the denominator of the F-ratio (the error
term) for a repeated-measures ANOVA compare
to the denominator for an independent-measures
ANOVA?
2. The repeated-measures ANOVA can be viewed as a
two-stage process. What is the purpose for the second
stage?
3. A researcher conducts an experiment comparing
four treatment conditions with n = 12 scores in each
condition.
a. If the researcher uses an independent-measures
design, how many individuals are needed for the
study and what are the df values for the F-ratio?
b. If the researcher uses a repeated-measures design,
how many individuals are needed for the study and
what are the df values for the F-ratio?
4. A researcher conducts a repeated-measures experiment
using a sample of n = 15 subjects to evaluate the
differences among three treatment conditions. If the
results are examined with an ANOVA, what are the
df values for the F-ratio?
5. The following data were obtained from a repeatedmeasures
study comparing three treatment conditions.
Use a repeated-measures ANOVA with α =.05 to
determine whether there are significant mean differences
among the three treatments.
Treatments
Person I II III
Person
Totals
A 0 2 4 P = 6
B 0 3 6 P = 9 N = 15
C 3 7 8 P = 18 G = 60
D 0 7 5 P = 12 ΣX 2 = 350
E 2 6 7 P = 15
M = 1 M = 5 M = 6
T = 5 T = 25 T = 30
SS = 8 SS = 22 SS = 10
6. The following data represent the results of a
repeated-measures study comparing different viewing
distances for a 42-inch high-definition television.
Four viewing distances were evaluated, 9 feet,
12 feet, 15 feet, and 18 feet. Each participant was
free to move back and forth among the four distances
while watching a 30-minute video on the
television. The only restriction was that each person
had to spend at least 2 minutes watching from each
of the four distances. At the end of the video, each
participant rated the all of the viewing distances on
a scale from 1 (Very Bad, definitely need to move
closer or farther away) to 7 (excellent, perfect
viewing distance).
a. Use a repeated-measures ANOVA with α =.05 to
determine whether there are significant difference
among the four viewing distances.
b. Compute η 2 to measure the size of the treatment
effect.
Person 9 Feet
Viewing Distance
12 Feet 15 Feet 18 Feet
Person
Totals
A 3 4 7 6 P = 20 n = 5
B 0 3 6 3 P = 12 k = 4
C 2 1 5 4 P = 12 N = 20
D 0 1 4 3 P = 8 G = 60
E 0 1 3 4 P = 8 ΣX 2 = 262
T = 5 T = 10 T = 25 T = 20
SS = 8 SS = 8 SS = 10 SS = 6
7. The following data were obtained from a repeatedmeasures
study comparing two treatment conditions.
Use a repeated-measures ANOVA with α = .05 to
determine whether there are significant mean differences
between the two treatments.
Person I II
Treatments
Person
Totals
A 3 5 P = 8
B 5 9 P = 14 N = 16
C 1 5 P = 6 G = 80
D 1 7 P = 8 ΣX 2
= 500
E 5 9 P = 14
F 3 7 P = 10
G 2 6 P = 8
H 4 8 P = 12
M = 3 M = 7
T = 24 T = 56
SS = 18 SS = 18