RE: BOV
From:"Liang Zhao" zhao.80@osu.edu
Subject: RE: [NMusers] BOV
Date: Wed, September 22, 2004 4:56 pm
Hi Qi,
In my understanding, if the variables are RANDOM, by way of viewing
the regression as orthogonal projections with condition that the sum of
residual distances to be 0 (another view point for the techniques used in
least square simple linear/nonlinear regressions), you can make these
assumptions. In addition, the distribution of BSV and BOV do follow normal
distributions with mean 0 by assumption in this case. The calculations based
on weighted least square or maximum likelihood approach for PPK are equivalent
if the RANDOM variables are assumed to be normally distributed. Please refer
to some nonlinear regression books by Bates for the concept of orthogonal
projection. In fact, a trick to validate the NONMEM outputs is to make sure
the sum of weighted residual is 0 if everything is normally distributed. Point
out if I am wrong.
Liang Zhao PhD
Division of Pharmaceutics
The Ohio State Univ.