ANOVA and ANCOVA

[CPhilipp]

How would one estimate an ancova model in stata? Is this the same command as when one runs an anova model?

Also, for an anova model if I am estimating an anova model with income as a dependent variable and race as an independent variable, but I need to code the dummy variable for race first.... does this look correct? Many thanks!! Struggling with this topic!

[Clyde Schechter]

Whatever you tried to post as a screen shot or attachment, didn't come through. So nobody knows whether it looks correct or not. Whatever code or output you want to share with us is best posted in a code block. Click on the underlined A button to open the advanced editor. Then click on the # button to bring up a pair of code block delimiters. Type or paste whatever you want to show between those delimiters.

In terms of generic questions: if you are using the -anova- command you do not need to create your own dummy variables. If you want to include a continuous covariate, you must prefix that variable name with c. to prevent -anova- from treating it as a categorical variable (with far too many levels).

[Richard Williams]

If you just type -help anova- you get plenty of examples, including for ancova. I would use regress commands myself but I suppose it depends on the traditions in your field.