Hi,
I would like to use a variable of interest along with its first order temporal derivative as the "seed" in my GLM analysis, as done for awkwardness ratings in this paper: https://www.ncbi.nlm.nih.gov/pmc/article...

In the secondary results section in Conn (2021), I see both "variable" and  "variable-der1" as an option to select as the seed. My question is, does the "variable-der1" include only the first order derivative or is it the original "variable" plus the "variable-der-1"?  So in other words, to achieve this analysis, would I select both "variable" and "variable-der1" or only "variable-der1"?  

Thank you!
~Em