NONMEM Users Network Archive

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RE: Omega ratio

From: Ribbing, Jakob <Jakob.Ribbing>
Date: Wed, 15 Jul 2009 18:51:18 +0100

Dear Khaled,

 

You could for example report this as "Including covariate X in the
model, the estimate of random (unexplained) between-subject variability
in parameter Y reduced from 41.8 %CV to 40.5 %CV".

 

Reporting % explained variability may lead to confusion on if this is in
percent or percental units or if it is on the CV scale or variance
(OMEGA) scale (3 different values that you can present), so I think the
above is easier to understand. If you prefer you can report it as r or
R^2, but the values are generally not very impressive.

 

Best

 

Jakob

 

________________________________

From: owner-nmusers
On Behalf Of Khaled Nm
Sent: 15 July 2009 12:07
To: nmusers
Subject: [NMusers] Omega ratio

 

Dear all,

 

I am still confused how to determine the % of explained variability by
including covariates from Omega . Omega estimate were 0.175 (before) and
0.164 (after). Objective function value decreased more than 150 units
and the goodness-of-fit plots confirmed the positive impact of this
covariate.

How these values should be treated?

 

Any feedback? thanks in advance

Khaled

 

 


Received on Wed Jul 15 2009 - 13:51:18 EDT

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