NONMEM Users Network Archive

Hosted by Cognigen

Re: R/S+ nlme ODE

From: Leonid Gibiansky <LGibiansky>
Date: Mon, 23 Nov 2009 13:57:38 -0500

Bill,
Thanks for the code although it seems to be not what I need (or I am
missing something). If understood the code correctly, you replace the
model coefficients with the ones generated according to the population
model. I need to fix population parameters and variance-covariance
matrix (as in your code) but then estimate individual parameters for a
specific subject, based on his data, rather than use random parameters
consistent with the population model.
Thanks
Leonid

--------------------------------------
Leonid Gibiansky, Ph.D.
President, QuantPharm LLC
web: www.quantpharm.com
e-mail: LGibiansky at quantpharm.com
tel: (301) 767 5566




Denney, William S. wrote:
> Hi Leonid,
>
> This is how to do it for fixed effects in R with a regular nlme model
> (I've not used nlmeODE). I don't have an example with generating new
> random variables.
>
> library(MASS)
> ## make a model named "model" here
> coef <- model$coefficients$fixed
> cov.matrix <- model$varFix
> new.coef <- as.data.frame(mvrnorm(n=10000, coef, cov.matrix,
> empirical=TRUE))
>
> Thanks,
>
> Bill
>
> -----Original Message-----
> From: owner-nmusers
> On Behalf Of Leonid Gibiansky
> Sent: Monday, November 23, 2009 11:50 AM
> To: nmusers
> Subject: [NMusers] R/S+ nlme ODE
>
> Dear All,
> This is off-topic but I tried to ask this question in R-help list and it
> was not successful: 132 email/day and no reply to this question:
>
> I have a population PK model in nlmeODE (R or S+ versions) and I need a
> posthoc (in Nonmem terminology) estimate: estimate individual parameters
> of new subjects given population parameters and variance-covariance
> matrix. Is this possible? If yes, could you send me a sample code?
>
> Thanks!
> Leonid
>
> --------------------------------------
> Leonid Gibiansky, Ph.D.
> President, QuantPharm LLC
> web: www.quantpharm.com
> e-mail: LGibiansky at quantpharm.com
> tel: (301) 767 5566
>
>
> Notice: This e-mail message, together with any attachments, contains information of Merck & Co., Inc. (One Merck Drive, Whitehouse Station, New Jersey, USA 08889), and/or its affiliates Direct contact information for affiliates is available at http://www.merck.com/contact/contacts.html) that may be confidential, proprietary copyrighted and/or legally privileged. It is intended solely for the use of the individual or entity named on this message. If you are not the intended recipient, and have received this message in error, please notify us immediately by reply e-mail and then delete it from your system.
>
>
Received on Mon Nov 23 2009 - 13:57:38 EST

The NONMEM Users Network is maintained by ICON plc. Requests to subscribe to the network should be sent to: nmusers-request@iconplc.com.

Once subscribed, you may contribute to the discussion by emailing: nmusers@globomaxnm.com.