## lmer / lme [General Sta­tis­tics]

Hi Nastia,

» I still struggle to understand what is the difference between lmer and lme in this case...

The syntax of the formula for random effects is different.

 mod <- lmer(logPK  ~ sequence + period + treatment +                      (1|subject),                      data = data) mod <- lme(log(PK) ~ sequence + period + treatment,                      random = ~1|subject,                      data = data, na.action = na.omit)

Important: If you have incomplete data, in lme() you have to use na.action = na.omit because the default na.action = na.fail would stop and throw an error.

The method to extract the PE and calculate the CI is also different. Hint: Lines 53–56 and 80–84 of the source-code of method.B.R.

Dif-tor heh smusma 🖖
Helmut Schütz

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