A convenience function that returns the theta parameters for a
merMod object.
Value
a vector of the covariance, theta, parameters from a merMod
Examples
(fm1 <- lmer(Reaction ~ Days + (Days | Subject), sleepstudy))
#> Linear mixed model fit by REML ['lmerMod']
#> Formula: Reaction ~ Days + (Days | Subject)
#> Data: sleepstudy
#> REML criterion at convergence: 1743.628
#> Random effects:
#> Groups Name Std.Dev. Corr
#> Subject (Intercept) 24.741
#> Days 5.922 0.07
#> Residual 25.592
#> Number of obs: 180, groups: Subject, 18
#> Fixed Effects:
#> (Intercept) Days
#> 251.41 10.47
thetaExtract(fm1) #(a numeric vector of the covariance parameters)
#> [1] 0.96674177 0.01516906 0.23090995