LMER对象的边际方差

Question

有人可以解释是否残差方差/标准差。开发。在下面的输出中给出的是边际或条件方差/标准。开发。我试图获得模型的边际方差。如果在summary（）函数中没有给出，你能告诉我如何获得它吗？谢谢！

library(lme4)
sleepstudy <- transform(sleepstudy,period=(Days<6.5))
m0 <- lmer(Reaction ~ Days+ (1 | Subject), sleepstudy)
m2 <- lmer(Reaction ~ Days*period+ (1 | Subject), sleepstudy)

Linear mixed model fit by REML ['lmerMod']
Formula: Reaction ~ Days * period + (1 | Subject) 
   Data: sleepstudy 

REML criterion at convergence: 1773.86 

Random effects:
 Groups   Name        Variance Std.Dev.
 Subject  (Intercept) 1377.8   37.12   
 Residual              964.5   31.06   
Number of obs: 180, groups: Subject, 18

Fixed effects:
                Estimate Std. Error t value
(Intercept)      207.008     42.533   4.867
Days              16.050      5.176   3.101
periodTRUE        45.908     41.922   1.095
Days:periodTRUE   -6.125      5.358  -1.143

Correlation of Fixed Effects:
            (Intr) Days   prTRUE
Days        -0.974              
periodTRUE  -0.972  0.988       
Dys:prdTRUE  0.941 -0.966 -0.980