Hello,

Why the correlation between the random effects is negative?
library(coxme)
rats1 <- coxme(Surv(time, status) ~ (1|litter), rats)
random.effects(rats1)[[1]] #one value for each of the 50 litters
print(rats1)

rats2 <- lmekin(time ~ (1|litter), rats)
fixed.effects(rats2)
random.effects(rats2)[[1]] #one value for each of the 50 litters
print(rats2)

cor(random.effects(rats1)[[1]],random.effects(rats2)[[1]])

Thanks

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