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Re: Deat Jun,the covariance?

From: saik.urien.svp <saik.urien>
Date: Mon, 14 Dec 2009 18:30:48 +0100

Dear Hongpo

Covariance between CL and V etas can be or should be observed for the =
oral route. CL and V are apparent parameters that are related by the =
unknown bioavailability : these are CL/F and V/F, so there is a =
physiological/pharmacological basis for the correlation.

  ----- Original Message -----
  From: yhb5442387
  To: nmusers
  Sent: Monday, December 14, 2009 4:10 PM
  Subject: [NMusers] Deat Jun,the covariance?

  Dear Jun:
  Sorry for making you in the reading trouble:
  Here is my question:
  Is there any special specification on the employ of covariance:
  The papers which I have read most always take the covariance =
excluded,such as W21,w31 w32.If the Decrease of OFV between the model of =
the covriance included and the one not is significantly meaningful,what =
choice should I do? I really do not understand the correlation of Cl and =
V,if the convariance between the two parameters does exist.Dose it truly =
exist in physiologically or just mathematically?

  Dear Hongpo,

  I am not sure I understand your question. Can you rephrase?

  Jun Shen
  Millipore Corporation

  2009/12/13 yhb5442387 <yhb5442387

    Dear professor:

    THE off diagnoal:

    Sometimes we make the OMEGA syntax as follows:$omega 0.1 0.1,but =
$omega blokc (2) 0.1 0.01 0.1 at another occasion.As we know,the only =
difference is whether the off diagonal estimate be used.So is there any =
specila condition about the existence of the W21,or some another W =
square like that?

    Thank you !!!



Received on Mon Dec 14 2009 - 12:30:48 EST

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