On 3 September 2010 12:03, zbynek.jano...@gmail.com <zbynek.jano...@centrum.cz> wrote: > > I am having problem using output of lm() function for further analysing using > systemfit package. > > Basicaly, the problem s following - I generate several formulas using lm() >> fo1 <- lm(r98[,2] ~ f98[,1] + f98[,2] + ... + f98[,43]) >> fo2 <- lm(r98[,1] ~ f98[,1] + f98[,2] + ... + f98[,43]) > > and than I want to estimate a general model using package systemfit. > >> fitsur <- systemfit("SUR",list(as.formula(fo),as.formula(foo))) > > and I get following error: > Error in systemfit("SUR", list(as.formula(fo), as.formula(foo))) : > argument 'formula' must be an object of class 'formula' or a list of > objects of class 'formula' > > and I am not able to find where the problem is. > The problem remains even when I try: >> fo1 <- r98[,2] ~ f98[,1] + f98[,2] + ... + f98[,43] >> fo2 <- r98[,1] ~ f98[,1] + f98[,2] + ... + f98[,43] > instead of using lm() > Could someone give me a hand? I am quite new to R, so possibly the solutions > is simple:)
Yes, the formula(s) must be the *first* argument of the systemfit() command, e.g.: R> fitsur <- systemfit( list(as.formula(fo),as.formula(foo)), method = "SUR" ) /Arne -- Arne Henningsen http://www.arne-henningsen.name ______________________________________________ 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.