From: "Joern Loetsch" <jloetsch@stanford.edu>
Subject: Exponent in sigmoid Emax model and ETA
Date: Sat, 28 Apr 2001 18:50:29 +0200

Dear all,=20
just a short question:

What is the best (or the first on should try, or the most common) model for interindividual variance of the exponent (gamma) of the sigmoid Emax model? Gamma+ETA(x) or should one take gamma *EXP(Eta(x)) ?

Thanx in advance
Regards
Jorn Lotsch
_______________________________________________________
Joern Loetsch, MD
pharmazentrum frankfurt
Department of Clinical Pharmacology
J.W.Goethe-University Frankfurt/Main
Theodor-Stern-Kai 7
D-60590 Frankfurt/Main, Germany
Phone: +49-69-6301-4589
Fax: +49-69-6301-7636

 

*****

 

From: Lewis B Sheiner <lewis@c255.ucsf.edu>
Subject: Re: Exponent in sigmoid Emax model and ETA
Date: Sat, 28 Apr 2001 16:30:19 -0700

Unless you have exquisite data and lots of it per person (in which case, you probably don't need a hierarchical mdoel), I would not allow gamma to vary betweeen individuals.
--
_/ _/ _/_/ _/_/_/ _/_/_/ Lewis B Sheiner, MD (lewis@c255.ucsf.edu)
_/ _/ _/ _/_ _/_/ Professor: Lab. Med., Biophmct. Sci., Med.
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