NONMEM Users Network Archive

Hosted by Cognigen

Re: Problem with HESSIAN

From: Leonid Gibiansky <LGibiansky>
Date: Mon, 29 Jun 2009 08:51:21 -0400

Note also that your models are not identical: in ADVAN4 realization, you
put random effect on ALAG1 while in ADVAN6 it is on F1.

Try to remove ALAG1 (or fix it at 0.0001 or some small value, before the
first observation). The error could be related to ALAG1 difficulties.

Also, start ADVAN6 problem with the final values of ADVAN4 problem
(could be with MAXEVAL=0), just to get something converged. It could be
even FO: just to start with something. Then, after you see that the bulk
part is correct, you can move on to sort out details.

Leonid

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




Brogren, Jacob wrote:
> Hi Leonid,
>
> I tried to change to ADVAN8/ADVAN9 and TOL=8. I get the same error message.
>
> By the way, Martin Brgstrand tiped me about (F+DEL)**2 instead of F**2+DEL since NONMEM might not like the concept of 0 raised to the power of 2. However, this didn't change the outcome.
>
> Best Regards
>
> Jacob
>
>
> --------------------------------------------------------------------------
> Confidentiality Notice: This message is private and may contain confidential and proprietary information. If you have received this message in error, please notify us and remove it from your system and note that you must not copy, distribute or take any action in reliance on it. Any unauthorized use or disclosure of the contents of this message is not permitted and may be unlawful.
>
> -----Original Message-----
> From: Leonid Gibiansky [mailto:LGibiansky
> Sent: 29 juni 2009 13:31
> To: Brogren, Jacob
> Cc: Nmusers (E-mail)
> Subject: Re: [NMusers] Problem with HESSIAN
>
>
> Jacob,
> DEL part is not needed (unless you do log-transform; and even then,
> there are better methods).
> Try TOL=8 and/or ADVAN8 ADVAN9
>
> Leonid
>
> --------------------------------------
> Leonid Gibiansky, Ph.D.
> President, QuantPharm LLC
> web: www.quantpharm.com
> e-mail: LGibiansky at quantpharm.com
> tel: (301) 767 5566
>
>
>
>
> Brogren, Jacob wrote:
>> Hi, thank's for the advice. Unfortunately neither "DEL=0.01" nor "S3=V3" resolved the issue. I've also tried log-transforming both sides with no improvement.
>>
>> Regards
>>
>> Jacob
>>
>>
>
Received on Mon Jun 29 2009 - 08:51:21 EDT

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.