JMP Analysis of Skull Measurements
The JMP statistical computing program allows you to quickly analyze numerical data.
Data are entered into a spreadsheet. The individual measurements are entered in a
column. Various analyses are available from either the JMP starter window or the pull
down menus. Distribution is a primary tool for displaying and summarizing the
distribution of numerical values. The basic output includes a histogram and box plot.
There is a five-number summary as well as the sample mean and standard deviation. It
automatically produces a 95% confidence interval for the population mean. To perform a
test of hypothesis, click on the red triangle next to the measurement name and click on
Test Mean. You can enter the null hypothesized value and click on OK. JMP will
display the value of the test statistic as well as the P-value for each of the possible
alternative hypotheses.
An annotated version of the JMP output appears on the reverse side of this handout.
Annotated JMP Output of Skull Measurements
Distributions
Sinus (mm)
4
2
20
30
40
Count Axis
6
Box plot
Histogram
50
Quantiles
100.0%
Maximum
42.000
75.0%
50.0%
25.0%
Quartile
Median
Quartile
40.000
33.000
27.000
0.0%
Minimum
25.000
Five Number
Summary
Moments
Mean
Std Dev
Std Err Mean
upper 95% Mean
lower 95% Mean
N
34
6.78233
2.5634798
40.272609
27.727391
7
Sample Mean
Sample Std Dev
95% Confidence Interval
Test Mean=value
Hypothesized Value
Actual Estimate
Df
Std Dev
Test Statistic
Prob > |t|
Prob > t
Prob < t
30
34
6
6.78233
t Test
1.5604
0.1697
0.0848
0.9152
Test Statistic
P-value