Page 211 - Intermediate Statistics for Dummies

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Part III: Comparing Many Means with ANOVA
together that whether you take the drug once or twice a day has no effect.
So factor A (dosage) is significant, and factor B (times per day) isn’t. Parallel
lines again means no interaction effect.
a.
2 times/day
Change in BP
1 time/day
10mg
20mg
b.
Change in BP
2 times/day
1 time/day
10mg (dosage) 30mg
20mg
30mg
(dosage)
c. 2 times/day
Change in BP 1 time/day
10mg 20mg 30mg
(dosage)
d.
Change in BP 2 times/day
1 time/day
10mg 20mg 30mg
Figure 11-1: (dosage)
Five
examples of e.
the results 2 times/day
from a
two-way Change in BP
ANOVA with 1 time/day
interaction.
10mg 20mg 30mg