1. When comparing only two treatment groups…
a. The F-ratio and the t-test will yield similar results
b. The F-ratio and the t-test will yield different results
c. The F-ratio won’t work
d. The t-test won’t work
2. A study that compares the effectiveness of five different drugs and a placebo has…
a. 2 factors and 5 levels
b. 1 factor and 6 levels
c. 5 factors and 1 level
d. 1 factor and 5 levels
3. The F-ratio is communicating
a. The ratio of systematic variance to error variance
b. The ratio of error variance to unsystematic variance
c. The ratio of systematic variance to treatment variance
d. The ratio of within-treatment variance to error variance
4. If η² for an ANOVA was 1 that would mean…
a. There was no treatment effect
b. There was no difference between the means
c. There was no within-treatment variance
d. All of the total variance was explained by the within-treatment variance
5. Compared to Tukey’s HSD, the Scheffe test is:
a. more likely to reject the null
b. more likely to make a Type I Error
c. less likely to make a Type I Error
d. less likely to retain the null
6. Increasing the total number of hypothesis tests run…
a. Decreases the probability of a Type I Error
b. Lowers alpha
c. Increases the probability of a Type I Error
d. Makes it harder to reject the null
7. Researchers followed a sample of 20 adults from their 30s into their 50s, recording whether they exercised regularly and if they followed a healthy diet. The researchers also measured the number of serious medical conditions the participants experienced. The researchers divided the sample into four conditions depending on their diet and exercise patterns.
Diet & Exercise
|
Only Exercise
|
Only Diet
|
Neither
|
1
|
1
|
8
|
10
|
0
|
7
|
14
|
15
|
6
|
7
|
12
|
19
|
5
|
1
|
17
|
12
|
3
|
4
|
9
|
19
|
SS = 26
|
SS = 36
|
SS = 54
|
SS = 66
|
a) Test the hypothesis that different patterns of diet and exercise lead to different amounts of serious medical conditions with alpha = .01. State the null & alternative hypotheses. Report your decision in a sentence.
b) Use the ANOVA table below to present the results of the ANOVA.
Source
|
SS
|
df
|
MS
|
F
|
Between
|
|
|
|
|
Within
|
|
|
|
|
Total
|
|
|
|
|
c) Find η² to determine the effect size. Report in a sentence what η² is telling us.
d) Use Tukey’s HSD to make all six comparisons between the lifestyles. For each of the six comparisons, report whether they are significantly different or not.
e) Based on your results, which lifestyle should people choose? Which ones should they avoid?
f) Use the Scheffe test to compare “Diet & Exercise” to “Only Diet” and report whether it is significantly different.
g) Use the Scheffe test to compare “Only Exercise” to “Only Diet” and report whether it is significantly different.