I'm running into a little problem when trying to run a mixed ANCOVA with two covariates. I can run the analysis correctly with each covariate separately, but when I try and put them in together - either in R using jmv::anovaRM , or directly in Jamovi.
In Jamovi it says "invalid argument type", and in R it says
Code: Select all
Error in !sapply(bsRows, function(x) x[1] == "Residual") :
invalid argument type
Is this a bug, or am I doing something wrong? I strongly anticipate it is the latter, but I'm not quite sure what exactly it is that I'm doing wrong, given that it does work when using each covariate separately. Any advice would be greatly appreciated!