Note that the standard errors in those cases is 0, so the calculation will involve division by 0.
Without your data, it's impossible to say what is causing this, but it could be perfect collinearity, I think.
2025 SAS Hackathon: There is still time!
Good news: We've extended SAS Hackathon registration until Sept. 12, so you still have time to be part of our biggest event yet – our five-year anniversary!
ANOVA, or Analysis Of Variance, is used to compare the averages or means of two or more populations to better understand how they differ. Watch this tutorial for more.