Please click on the following link and save it to your desktop:
Annual Mileage 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 quickly calculate a z-score for each observation in this data set we will have to create a new column.
Clicking on the next available column after Car Type will do this.
You can change Column Name in which I changed to Z-score.
Now we can move onto calculating our Z-scores.
First click on the drop down arrow next to Column Properties and select Formula.
To edit this column, double-click on Column 4. This dialog box will appear.
Select Edit Formula.
The following screen will then appear:
Now remember the formula for calculating a z-score is:
To start this formula click on the division icon:
Your formula should now look like this:
To begin select Annual Miles under the Table Columns section then select the Subtract icon.
Next, under Functions (grouped), select Statistical then Col Mean.
Your formula should now look like the following:
Then again go back to Table Columns and select Annual Miles.
Moving to the denominator, make sure you click on the small box so that it is outlined in red and go back to Functions (grouped) select Statistical then Col Std Dev. Afterwards, go to Table Columns again and select Annual Miles.
Your final formula should look like the following.
Click ok, and ok again. This will then populate the column that you created with standardized values for the variable (Z-scores).
You can also now quickly calculate a Z-score for any value you would like.
For instance, in the column Annual Miles I put in 20000 and JMP automatically calculated the Z-score for that variable which is 1.401.
