[R] Generate bivariate binomial data

[ONKELINX, Thierry]

Dear all,

Could someone point me to a function or algorithm to generate random
bivariate binomial data? 

Some details about what I'm trying to do. I have a dataset of trees who
were categorised as not damaged or damaged. Each tree is measured twice
(once in two consecutive years). The trees can recover from the damage
but the data is clearly correlated. As a (un)damaged tree is more likely
to stay (un)damaged. A GEE-model indicates a correlation of about 0.6
between the measures on the same tree.
I need to simulate similar dataset to do some power calculations.

Best regards,

Thierry

------------------------------------------------------------------------
----
ir. Thierry Onkelinx
Instituut voor natuur- en bosonderzoek / Research Institute for Nature
and Forest
Cel biometrie, methodologie en kwaliteitszorg / Section biometrics,
methodology and quality assurance
Gaverstraat 4
9500 Geraardsbergen
Belgium 
tel. + 32 54/436 185
Thierry.Onkelinx at inbo.be 
www.inbo.be 

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say what the experiment died of.
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ensure that a reasonable answer can be extracted from a given body of
data.
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