[R] Questions about extract-lme.cov

From: Li, Hua <HUL_at_stowers-institute.org>
Date: Sat 15 Jul 2006 - 02:18:33 EST


Hi, all:

I am using extract.lme.cov to extract the covariance matrix of lme. But the results are not expected.

For example,

 b <- lme(travel~1,Rail,~1|Rail)

The default correlation for lme is no correlation within groups.

>extract.lme.cov(b,Rail)

The part of covariance matrix looks like:

         1 2 3 4 5 6

1 631.4778 615.3111 615.3111   0.0000   0.0000   0.0000
2 615.3111 631.4778 615.3111   0.0000   0.0000   0.0000
3 615.3111 615.3111 631.4778   0.0000   0.0000   0.0000
4   0.0000   0.0000   0.0000 631.4778 615.3111 615.3111
5   0.0000   0.0000   0.0000 615.3111 631.4778 615.3111
6   0.0000   0.0000   0.0000 615.3111 615.3111 631.4778

Where does the covariance come from? Maybe I'm missing sth here?

Thanks,

Hua Li

        [[alternative HTML version deleted]]



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 Received on Sat Jul 15 02:23:18 2006

Archive maintained by Robert King, hosted by the discipline of statistics at the University of Newcastle, Australia.
Archive generated by hypermail 2.1.8, at Sat 15 Jul 2006 - 20:14:43 EST.

Mailing list information is available at https://stat.ethz.ch/mailman/listinfo/r-help. Please read the posting guide before posting to the list.