Viewing standard errors and parameter estimates in lme4

Question

I just started working with the lme4 package for linear mixed models in R. I started following along the book by Douglas Bates, in order to to understand the process. In the book, the output for a model fit using the 'sleepstudy' dataset in the package is given as:

Linear mixed model fit by maximum likelihood [✬merMod✬]
Formula: Reaction ~ 1 + Days + (1 + Days | Subject)
Data: sleepstudy
AIC BIC logLik deviance
1763.9393 1783.0971 -875.9697 1751.9393
Random effects:
Groups Name Variance Std.Dev. Corr
Subject (Intercept) 565.52 23.781
Days 32.68 5.717 0.081
Residual 654.94 25.592
Number of obs: 180, groups: Subject, 18
Fixed effects:
Estimate Std. Error t value
(Intercept) 251.405 6.632 37.91
Days 10.467 1.502 6.97
Correlation of Fixed Effects:
(Intr)
Days -0.138

However, when I fit the same model,

fm06 <- lmer(Reaction~1 + Days + (1 + Days|Subject),sleepstudy,REML =FALSE)

I get a different output, without the standard error estimates. This is how my output looks like:

    Linear mixed model fit by maximum likelihood  ['lmerMod']
Formula: Reaction ~ 1 + Days + (1 + Days | Subject)
   Data: sleepstudy
      AIC       BIC    logLik  deviance  df.resid 
1763.9393 1783.0971 -875.9697 1751.9393       174 
Random effects:
 Groups   Name        Std.Dev. Corr
 Subject  (Intercept) 23.781       
          Days         5.717   0.08
 Residual             25.592       
Number of obs: 180, groups:  Subject, 18
Fixed Effects:
(Intercept)         Days  
     251.41        10.47 

I am not sure what I am doing wrong, if anything, or how to view the parameter and standard error estimates of the variance components. Can somebody give me some pointers? Much appreciated!!

Answer 1

Try summary(fm06). This gives the desired output.