R help - Jan 2024 - how to specify uncorrelated random effects in nlme::lme()

Dear professor,


I'm using package nlme, but I can't find a way to specify two
uncorrelated random effects. For example, a random intercept and a random slope.
In package lme4, we can specify x + (x ll g) to realize, but how in
nlme?


Thanks!








 ????????????????????????
 Zhen Wang
 Graduate student, Department of Medical Statistics, School of Public Health,
Sun Yat-sen University
E-mail: wangzh597 at mail2.sysu.edu.cn
??
????????????????2022??????
	[[alternative HTML version deleted]]

Dear Zhen,

You can use this with pdDiag(). An example:

library(nlme)
res <- lme(distance ~ age*Sex, random = list(Subject = pdDiag(~ age)),
data=Orthodont)
summary(res)

Best,
Wolfgang
> -----Original Message-----
> From: R-help <r-help-bounces at r-project.org> On Behalf Of ??
> Sent: Monday, January 8, 2024 12:43
> To: R-help <R-help at r-project.org>
> Subject: [R] how to specify uncorrelated random effects in nlme::lme()
>
> Dear professor,
>
> I'm using package nlme, but I can't find a way to specify two
uncorrelated
> random effects. For example, a random intercept and a random slope. In
package
> lme4, we can specify&nbsp;x + (x ll g) to realize, but how in nlme?
>
> Thanks!
>
> ????????????????????????
>  Zhen Wang
>  Graduate student, Department of Medical Statistics, School of Public
Health,
> Sun Yat-sen University
> E-mail:&nbsp;wangzh597 at mail2.sysu.edu.cn
> ??
> ????????????????2022??????