Hi all, I would like to apply the vcov function from the survey package for the variables api00 and api99 grouped by the stype variable which can assume H, M and E categories (see below)
I have tried svyby but as far as I know covariant matrices don't work with this function In the code example (survey package manual) they apply the as.svrepdesign and then svyby with svymean function but I need svyby with svytotal without as.svrepdesign. data(api) dclus1<-svydesign(id=~dnum, weights=~pw, data=apiclus1, fpc=~fpc) rclus1<-as.svrepdesign(dclus1) mns<-svyby(~api00, ~stype, rclus1, svymean,covmat=TRUE) vcov(mns) how to mix the different stypes to obtain terms like: api00:H api00:H api00:H api00:M api00:H api00:E api00:H api99:H api00:H api99:M api00:H api99:E api00:E api00:E api00:E api00:M api00:E api99:H api00:E api99:E api00:E api99:M api00:M api00:M api00:M api99:H api00:M api99:E api00:M api99:M api99:H api99:H api99:H api99:E api99:H api99:M api99:E api99:E api99:E api99:M api99:M api99:M I have no clue on how to implement that. Thanks a lot! Daniela. [[alternative HTML version deleted]] ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.