lmer / lme [General Sta­tis­tics]

posted by Helmut Homepage – Vienna, Austria, 2019-12-25 19:12 (481 d 00:30 ago) – Posting: # 21030
Views: 4,028

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 +
                     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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