Anna.H.Persson@astrazeneca.com
2004-Jul-23 10:36 UTC
[R] confidence intervals for linear combinations when using lme
Hi I really hope someone can help me. I have just started to work with S-plus, and have not yet understood how it really works. I am now trying to fit a mixed effects model with lme. My goal is to compare four different groups, at several different time points, and I therefore would like to create confidence intervals for linear combinations of my estimated parameters (as I usually do with "contrast" or "estimate" or "lsmeans" in SAS). I have now found out that the vcov-function in the lme4-package could be of great help for me, but I do not know if I can use lme4 when working with S-PLUS 6.1, or is it only for R. When I write>library(MASS)I find lme3, where there is a vcov-function, but if I understand it correctly it works with lm and not with lme... If I can use lme4 with s-plus 6.1, what shall I do in order to install it on my computer? I am grateful for all help I can get? best regards Anna Persson
Deepayan Sarkar
2004-Jul-23 11:58 UTC
[R] confidence intervals for linear combinations when using lme
On Friday 23 July 2004 05:36, Anna.H.Persson at astrazeneca.com wrote:> Hi > > I really hope someone can help me. > > I have just started to work with S-plus, and have not yet understood > how it really works. I am now trying to fit a mixed effects model > with lme. My goal is to compare four different groups, at several > different time points, and I therefore would like to create > confidence intervals for linear combinations of my estimated > parameters (as I usually do with "contrast" or "estimate" or > "lsmeans" in SAS). I have now found out that the vcov-function in the > lme4-package could be of great help for me, but I do not know if I > can use lme4 when working with S-PLUS 6.1, or is it only for R.As far as I know, there are no plans (by the developers) to port lme4 to work with S-PLUS. Deepayan
Douglas Bates
2004-Jul-23 12:05 UTC
[R] confidence intervals for linear combinations when using lme
Anna.H.Persson at astrazeneca.com wrote:> I have just started to work with S-plus, and have not yet understood how it > really works. I am now trying to fit a mixed effects model with lme. My goal > is to compare four different groups, at several different time points, and I > therefore would like to create confidence intervals for linear combinations > of my estimated parameters (as I usually do with "contrast" or "estimate" or > "lsmeans" in SAS). I have now found out that the vcov-function in the > lme4-package could be of great help for me, but I do not know if I can use > lme4 when working with S-PLUS 6.1, or is it only for R.The lme4 package is only available for R at this time.