Question

Some studies show that people who think they are intoxicated will show signs of intoxication, even if they did not consume alcohol. To test whether this is true, researchers had a group of five adults consume nonalcoholic drinks, which they were told contained alcohol. The participants completed a standard driving test before drinking and then after one nonalcoholic drink and after five nonalcoholic drinks. A standard driving test was conducted in a school parking lot where the participants had to maneuver through traffic cones. The number of cones knocked over during each test was recorded. The following table lists the data for this hypothetical study. Driving Test Before Drinking After One Drink After Five Drinks 0 1 3 0 1 2 2 2 3 3 2 5 0 1 0 (a) Complete the F-table. (Round your answers to two decimal places.) Source of Variation SS df MS Fobt Between groups Between persons Within groups (error) Total (b) Compute a Bonferroni procedure and interpret the results. (Assume experimentwise alpha equal to 0.05. Select all that apply.) Students knocked over significantly more cones after 1 nonalcoholic drink compared with the driving test prior to drinking. Students knocked over significantly more cones after 5 nonalcoholic drinks compared with the driving test after 1 nonalcoholic drink. Students knocked over significantly more cones after 5 nonalcoholic drinks compared with the driving test prior to drinking. There were no significant differences between any of the groups.

Answer 1

a)

Driving Test Before Drinking	After One Drink	After Five Drinks
0	2	2
1	2	5
3	2	0
0	3	1
1	3	0

result

Anova: Two-Factor Without Replication
SUMMARY	Count	Sum	Average	Variance
1	3	4	1.333333333	1.333333333
2	3	8	2.666666667	4.333333333
3	3	5	1.666666667	2.333333333
4	3	4	1.333333333	2.333333333
5	3	4	1.333333333	2.333333333
Driving Test Before Drinking	5	5	1	1.5
After One Drink	5	12	2.4	0.3
After Five Drinks	5	8	1.6	4.3
ANOVA
Source of Variation	SS	df	MS	F	P-value	F crit
between person	4	4	1	0.392156863	0.809008162	3.837853355
Between groups	4.933333333	2	2.466666667	0.967320261	0.420485786	4.458970108
error	20.4	8	2.55
Total	29.33333333	14