R help - Sep 2008 - glmer -- extracting standard errors and other statistics

Hello,

I am using glmer() from lmer(lme4) to run generalized linear mixed 
models.  However, I am having a problem extracting the standard errors 
for the fixed effects.

I have used:

summary(model)$coef
fixed.effects(model)
coef(model)

to get out the parameter estimates, but do not seem able to extract the 
se's.

Anybody have a solution?

Thanks,
John

John Poulsen schrieb:
> Hello,
> 
> I am using glmer() from lmer(lme4) to run generalized linear mixed 
> models.  However, I am having a problem extracting the standard errors 
> for the fixed effects.
> 
> I have used:
> 
> summary(model)$coef
> fixed.effects(model)
> coef(model)
> 
> to get out the parameter estimates, but do not seem able to extract the 
> se's.
> 
> Anybody have a solution?
> 
You need to extract the variance-covariance matrix:

library(lme4)

gm1 <- glmer(cbind(incidence, size - incidence) ~ period + (1 | herd), 
              family = binomial, data = cbpp))

sqrt(diag(vcov(gm1)))


HTH,

Bernd