The twin tag has no wiki summary.
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Mixed-effects model for MZ twin data: avoiding overparametrization
I'm trying to fit a (simple) linear regression using MZ twin data. The reason why mixed-effects are used here is just to correct for correlated responses from the twins.
The current model looks like ...
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Choice of referent twin in twin difference model
Carlin (2005) points out that mixed effects models specifically for twin data can be simplified by calculating differences between paired clusters. This allows for modeling specifically the within ...
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How to account for different degrees of familial relatedness in linear mixed model? Is heteroscedasticity a problem?
(Let me preface this by stating that I am somewhat of an R newb and also a LMM newb.)
I have a very, very simple research question. I have a continuous outcome variable ("HAPPY"). I have two factors ...
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Linear mixed-effects modeling with twin study data
Suppose I have some some response variable $y_{ij}$ that was measured from $j$th sibling in $i$th family. In addition, some behavioral data $x_{ij}$ were collected at the same time from each subject. ...
