Re: OMEGA BLOCK with mixture model?

Andreas, Thanks for the suggestion. However, I think its only necessary to enforce 0 to 1 boundaries on the individual value of F1 when one is modelling absolute bioavailability. In this example I gave the individual 'apparent' bioavailability can be due to a variety of differences from the implicit mean of 1 (e.g. actual bioavailability, protein binding, dose errors, etc). The only constraint required is that F1 be non-negative. This is taken care of by the use of EXP transformation of ETA. Nick andreas lindauer wrote: > Nick, > > In your code example for the estimation of a 'relative bioavailability' wouldn't it be necessary to use a logit transformation to keep F1 between 0 and 1? Something like: F1 = 1/(1+exp(BSV_F1)) > > Regards, Andreas. > > ____________________________ > > Andreas Lindauer > > Department of Clinical Pharmacy > > Institute of Pharmacy > > University of Bonn > > An der Immenburg 4 > > D-53121 Bonn > > phone: + 49 228 73 5781 > > fax: + 49 228 73 9757 -- Nick Holford, Dept Pharmacology & Clinical Pharmacology University of Auckland, 85 Park Rd, Private Bag 92019, Auckland, New Zealand [email protected] tel:+64(9)923-6730 fax:+64(9)373-7090 mobile: +33 64 271-6369 (Apr 6-Jul 17 2009) http://www.fmhs.auckland.ac.nz/sms/pharmacology/holford