Investigators are interested in a small exploratory study looking a continuous m
ID: 3180476 • Letter: I
Question
Investigators are interested in a small exploratory study looking a continuous measure taken on three different formulations. Because they expect variability between batches they ran a blocked design where they blocked on the batch. The data are given below. https://home.ubalt.edu/ntsbarsh/Business-stat/otherapplets/ANOVATwo.htm Test for difference between mean responses for the three treatments ignoring batch in the model. What can you conclude? Justify your answer. Re-test the above adjusted for the batch. What do you conclude about mean responses? How does this differ from the prior analyses? Data in the table is a study of blood pressure for different doses (DOSAGE) and different of times used (TIMES). How many different doses were included in the study? Based just on the table what can you conclude about dosage and times applied?Explanation / Answer
Answer:
1).
One factor ANOVA
Mean
n
Std. Dev
69.3
4
2.22
A
69.8
4
4.11
B
59.5
4
7.59
C
66.2
12
6.78
Total
ANOVA table
Source
SS
df
MS
F
p-value
Treatment
267.17
2
133.583
5.04
.0340
Error
238.50
9
26.500
Total
505.67
11
Calculated F=5.04, P=0.034 which is < 0.05 level of significance.
There is significant mean difference between three treatments.
2).
Randomized blocks ANOVA
Mean
n
Std. Dev
69.250
4
2.217
A
69.750
4
4.113
B
59.500
4
7.594
C
63.333
3
9.074
Batch1
64.333
3
4.041
Batch2
64.667
3
8.386
Batch3
72.333
3
2.517
Batch4
66.167
12
6.780
Total
ANOVA table
Source
SS
df
MS
F
p-value
Treatments
267.17
2
133.583
9.60
.0135
Blocks
155.00
3
51.667
3.71
.0805
Error
83.50
6
13.917
Total
505.67
11
Calculated F=9.60, P=0.0135 which is < 0.05 level of significance.
There is significant mean difference between three treatments.
In this analysis, we are controlling variation between blocks.
3a)
Three
3b).
The interaction between Dosage and Time is significant, but main effects of Dosage and Time are not significant.
One factor ANOVA
Mean
n
Std. Dev
69.3
4
2.22
A
69.8
4
4.11
B
59.5
4
7.59
C
66.2
12
6.78
Total
ANOVA table
Source
SS
df
MS
F
p-value
Treatment
267.17
2
133.583
5.04
.0340
Error
238.50
9
26.500
Total
505.67
11
Related Questions
drjack9650@gmail.com
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.