I have a bunch of data which is structured by year and US state, so I have created a nlme groupedData object for it:
formula(gd2) DEPVAR ~ YEAR | ABREV Now I am trying to run a gls regression on it. I want the error correlation structure to be AR1 with a different rho for each state, so I do > mdyn.1.1 = gls(model = DEPVAR ~ BLAH + BLAH, data=gd2, corr=corAR1(form= ~ > YEAR | ABREV),na.action=na.omit) YEAR and ABREV are always present; DEPVAR is absent for one state. I get the following error message: Error in logLik.glsStruct(glsSt, glsPars) : Deficient rank in gls_loglik Can anyone enlighten me? The error message goes away if I just do corAR1(form = ~1), but this is not meaningful for my data. Cheers David ______________________________________________ R-help@stat.math.ethz.ch mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html