JMP Analysis of Blood Pressure Data
Enter the data into two columns:
Group – Data Type is Character, Modeling Type is Nominal
Blood Pressure – Data Type is Numeric, Modeling Type is Continuous
Go to Basic in the JMP Starter
Click on Oneway
Enter Blood Pressure for the Y, Response and Group for the X, Grouping
Click on OK
Oneway Analysis of Blood Pressure By Group
135
Blood Pressure
130
125
120
115
110
105
1
2
Group
Click on the Red Triangle next to Oneway Analysis of Blood Pressure By Group
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Means/ANOVA/Pooled t – Performs and ANalysis of VAriance and two-sample t-test
assuming equal variances. (STAT 401)
Oneway Analysis of Blood Pressure By Group
Oneway Anova
Summary of Fit
Rsquare
Adj Rsquare
Root Mean Square Error
Mean of Response
Observations (or Sum Wgts)
0.348247
0.266778
7.341662
121.8
10
Analysis of Variance
Source
Group
Error
C. Total
DF
1
8
9
Sum of Squares
230.40000
431.20000
661.60000
Mean Square
230.400
53.900
F Ratio
4.2746
Prob > F
0.0725
Means for Oneway Anova
Level
1
2
Number
5
5
Mean
117.000
126.600
Std Error
3.2833
3.2833
Lower 95%
109.43
119.03
Upper 95%
124.57
134.17
Std Error uses a pooled estimate of error variance
This is the same procedure used for the two-sample t-test assuming equal variances. The
output from the analysis of variance is displayed above. The value of the F-test statistic
is 4.2746 (this is the value of the t-test statistic squared) with a two-sided P-value of
0.0725. Group 2 has a sample mean that is different from the sample mean for Group 1
and that difference is not statistically significant. The analysis of variance considers a
two-sided alternative hypothesis so there is no contradiction with the earlier results.
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