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Use predict() after lmer() (library lme4)

1 message · Thierry Onkelinx

#
Dear Marc,

This question is more suited for R-Sig-mixed models to which I'm forwarding
it.

Your manual predictions for out3 are wrong. Here are the correct manual
predictions.

fixed <- model.matrix(~effect, data = dataF) %*% fixef(out3)
random <- rowSums(model.matrix(~Sector, data = dataF) *
ranef(out3)$Beach[dataF$Beach, ])
range(fixed + random - predict(out3))

Best regards,


ir. Thierry Onkelinx
Instituut voor natuur- en bosonderzoek / Research Institute for Nature and
Forest
team Biometrie & Kwaliteitszorg / team Biometrics & Quality Assurance
Kliniekstraat 25
1070 Anderlecht
Belgium

To call in the statistician after the experiment is done may be no more
than asking him to perform a post-mortem examination: he may be able to say
what the experiment died of. ~ Sir Ronald Aylmer Fisher
The plural of anecdote is not data. ~ Roger Brinner
The combination of some data and an aching desire for an answer does not
ensure that a reasonable answer can be extracted from a given body of data.
~ John Tukey

2016-02-03 8:08 GMT+01:00 Marc Girondot <marc_grt at yahoo.fr>: