JMP Tutorial: Calculating a Z-Test
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Calculating a Z-Test (with Video)
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Please click on the following link and save it to your desktop: Distributions Data

Now go to your desktop and double click on the JMP file.
This process will automatically start JMP and display the following dataset.


To calculate a one-sample z test based on the dataset we will begin by clicking Analyze and selecting Distribution.


The following dialog box will appear.


For this z test we will be examining the height of 8th graders.
Select Height of 8th Graders (in) and then press the Y,Columns button to add the variable into the column roles.
Your dialog box should now appear as follows:


Click OK and the following window should appear.


Move and click your cursor on the red arrow next to Distributions and select Stack.


Now move your cursor and click the red arrow next to Height of 8th Graders(in) and select Test Mean.


The following dialog box should appear:


For Specify Hypothesized Mean, we will plug in 65. To perform a z test we must enter the true standard deviation of the population, which in this example will assume to be 6 (inches).


Then click OK.


Prob > |z| = 0.0015 represents the p-value for HA: µ ≠ 65.
Prob > z = 0.9993 represents the p-value for HA: µ > 65.
Prob < z = 0.0007 represents the p-value for HA: µ < 65.