Re: [R] Regression with groups and nested sub-groups

To be clear, this: >> How can I get the output to show all 3 groups that I have inputted? There >> are only group 2 and group 3 on the output, group 1 is missing. Also there >> is a subgroup (subgroup 1) of the total 9 subgroups missing. I would like >> to see the p-value of the missing group a

Re: [R] Regression with groups and nested sub-groups

Hi Robert, In R, the default treatment contrasts for factor class variables in regression treats the first level as the reference group when creating the contrast matrix for the regression, so it is not really a matter of changing the formula. This might provide some insight: http://www.ats.ucla.