Dear list,

I´m using the mgcv package to model the proportion by weight of certain prey
on the stomach content of a predator.  This proportion is the ratio of two
weights (prey weight over stomach weight), and ranges between 0 and 1.  The
variance is low when proportion is close to 0 and 1, and higher at
intermediate values.

It seems that the best way to go is to model this using the "quasi" family
with a logit link and a mu(1-mu) variance.  Or I am missing something
obvious?  I will be thankful for any input.

All the best,

Julian

-- 
Julian Mariano Burgos
Hafrannsóknastofnunin/Marine Research Institute
Skúlagata 4, 121 Reykjavík, Iceland
Sími/Telephone : +354-5752037
Bréfsími/Telefax:  +354-5752001
Netfang/Email: julian@hafro.is, jmburgos@uw.edu

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