On Tue, 19 May 2009, Stephen J. Barr wrote:
Hello,
I am working on a data set (already as a plm.data object) located here: http://econsteve.com/arch/plmWithDensity.Robj With the following R session: > library(plm) ... >load("plmWithDensity.Robj") >model <- plm(RATE ~ density08, data=plmWithDensity) Error: subscript out of bounds I am not understanding the "subscript out of bounds" error, as this is
I agree that the error is not very meaningful but the problem is due to your data: density08 does not vary within your id variable (COURT), hence the default within model cannot be estimated. And it is also the reason why density08 gets no coefficient in a larger model.
Also note that your RATE variable is a factor...I'm pretty certain you want a numeric variable here!
Yves & Giovanni: What happens in the code is that the model.matrix() method silently omits the column from the regressor matrix. Hence, this goes unnoticed in the larger model and results in a regressor matrix without any columns in the case above. Thus, the subscript error.
hth, Z ______________________________________________ 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.
