# Conduct Regression Error Normality Tests

Conduct Regression Error Normality Tests##
Minitab^{®}
– Procedure

If you haven't already done so, store the residuals on which you want to conduct the Ryan Joiner correlation test.

- Select
**Stat**>**Regression**>**Regression >****Fit Regression Model...** - Specify the response and the predictor variable(s).
- Select
**Storage...**Under**Diagnostic Measures**, select the type of residuals (and/or influence measures) that you want to store. Select**OK**. - Select
**OK**. The requested residuals (and/or influence measures) will be stored in your worksheet.

Once Minitab has stored the residuals in your worksheet:

- Select
**Stat**>**Basic Statistics**>**Normality Test****...** - In the box labeled
**Variable**, specify the name of the variable containing the residuals (Minitab names it something like RESI1, RESI2, ...). - Under
**Tests for Normality**, select**Anderson-Darling****,****Ryan-Joiner****,****or**.**Kolmogorov-Smirnov** - Select
**OK**. A new graph window containing the requested normal probability plot should appear.

##
Example

The data set adaptive.txt contains the Gesell adaptive scores and ages (in months) of *n* = 21 children with cyanotic heart disease. Upon regressing the response *y* = score on the predictor *x *= age, use the resulting residuals to test whether or not the error terms are normally distributed.

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