Hallo s-news,
I used lme to fit a linear mixed effects model as follows:
lme(y~ time + x2 + x3 + x4, random= list(center=~1, pid=~time, data=work)
My qqnorm-plot is heavy tailed, because of a lot of outliers, so the
residuals are not normally distributed. In Pinheiro and Bates (2000) I
read that this would lead to conservative tests. One of my fixed effects
has an p-value of 0.059 in the summary t-test, thus I have to exclude it
from the model. Does anybody know, if there is a better test with "true"
p-values or how to deal with this data?
Thank you in advance
Birgit
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