Dear "plm"-Package insiders, [I posted the following observation is April already but unfortunately I am not aware of any answers. With the hope that someone found an answer in the mean time, I ask again:]
I realized the following difficulty with the summary.plm function (demonstrated with the example from the ?plm documentation). library(plm) data("Produc", package="Ecdat") estimation_method<-"within" estimation_effect<-"individual" zz <- plm(log(gsp)~log(pcap)+log(pc)+log(emp)+unemp, data=Produc, index=c("state","year") , method=estimation_method , effect=estimation_effect ) summary(zz) #Error: object of type 'symbol' is not subsettable #But if I run zz <- plm(log(gsp)~log(pcap)+log(pc)+log(emp)+unemp, data=Produc, index=c("state","year") , method="within" , effect="individual" ) summary(zz) #the summary function works fine. Is it wrong (or bad practice) to define the function's parameters as I did in the upper example? If yes, how should it be done correctly such that the summary function works? I am running R version 2.9.1 wie plm version 1.1-4 on a Windows XP workstation. I checked, and the same issue occurs under Linux (Ubuntu). Thank you for your advice, Ulrich Morawetz ______________________________________________ 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.