Confidence Intervals and Prediction Intervals for Regression Response

Click the link below and save the following JMP file to your Desktop:

Now go to your Desktop and double click on the JMP file you just downloaded.

This action will start JMP and display the content of this file:

Go to the **Analyze** menu and select **Fit Y by X**:

Click the column **Gross Sales**, then click **Y, Response**.

Click the column **Items**, then click **X, Factor**.

Your screen should now look similar to the following:

Click **OK**.

The scatter plot is produced:

Click on the red down arrow next to **Bivariate Fit of Gross Sales By Items**
and select **Fit Line**:

You should see:

Click the red down arrow next to **Linear Fit** and pull to **Confid
Shaded Fit**:

You should now see, on the scatter plot, the 95% confidence interval for the
** mean** value of y for a given value of x for all values of x.

Click again on the red down arrow next to **Linear Fit** and pull to **
Confid Shaded Indiv**:

You should now also see, on the scatter plot, the 95% prediction interval for
a __ single__ value of y for a given value of x for all values of x. Notice these bands
are wider than the confidence interval bands:

If you wish to display 99% confidence and prediction intervals rather than
95%, click the red down arrow next to** Linear Fit**, go to **Set
α Level**, then 0.01.

You should see both sets of bands get wider: