You can try dissecting the output of VarCorr(ggg)
but, once again, I can't guarantee that it's what you want because we can't fit your model, and you have not sent us a simple, reproducible example. Andrew On Tue, May 30, 2006 at 03:37:19AM -0700, Pryseley Assam wrote: > Dear R-Users > > I have a problem accessing some values in the output from the summary of an > lme fit. > > I fit the model below: > > ggg <- lme (ST~ -1 + as.factor(endp):Z.sas + as.factor(endp), data=dat4a, > random=~-1 + as.factor(endp) + as.factor(endp):Z.sas|as.factor(trials), > correlation = corSymm(form=~1|as.factor(trials)/as.factor(id)), > weights=varIdent(form=~1|endp)) > > hh <- summary(ggg) > hh > > Below is the following part of the output of interest: > > Correlation Structure: General > Formula: ~1 | as.factor(trials)/as.factor(id) > Parameter estimate(s): > Correlation: > 1 > 2 0.785 > Variance function: > Structure: Different standard deviations per stratum > Formula: ~1 | endp > Parameter estimates: > -1 1 > 1.0000000 0.9692405 > > I wish to access the value of the correlation (0.785) and the vector of the > variance function estimates (1,0.969). I know these can be done throught the > intervals function, but sometimes when the estimated Hessian matrix is not > positive definite or something like that (i am not quite sure), the intervals > function delivers an error message. > > Thus, i will like to ask if there is another way to access these values. I > tried using the following code: > > hh$modelStruct$corStruct[1] > hh$modelStruct$varStruct[1] > > Rather the output was: > > > hh$modelStruct$corStruct[1] > [1] -1.308580 > > hh$modelStruct$varStruct[1] > [1] -0.03124255 > > I presume there is a way to calculate the correlation and variance function > coefficients using these values. > > Could someone tell me how to access those values (without using the > intervals function) or better still how to calculate the values from the last > output values. > > Kind regards > Pryseley > > > > > --------------------------------- > > [[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 -- Andrew Robinson Department of Mathematics and Statistics Tel: +61-3-8344-9763 University of Melbourne, VIC 3010 Australia Fax: +61-3-8344-4599 Email: [EMAIL PROTECTED] http://www.ms.unimelb.edu.au ______________________________________________ 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