Hi
Consider the case where we have a categorical (potentially time-varying)
covariate named CAT that can take several values (e.g. 0,1,2,3).
Let's say I want to model CL depending on this categorical covariate (where
parameters are estimated on log-scale).
A simple solution to this would be
IF(CAT.EQ.1) TVCL = THETA(1)
IF(CAT.EQ.2) TVCL = THETA(2)
IF(CAT.EQ.3) TVCL = THETA(3)
I let CL be described by a log-normal distribution with the same omega element
for all CAT values.
CL = EXP(TVCL + ETA(1))
With an omega statement:
$OMEGA 0.1
I now want to switch to the mu referencing framework in NONMEM. Each theta
needs to be reference to a MU value, and to force it to be described by the
same eta I apply the following approach.
MU_1 = THETA(1)
MU_2 = THETA(2)
MU_3 = THETA(3)
IF(CAT.EQ.1) CL = EXP(MU_1 + ETA(1))
IF(CAT.EQ.2) CL = EXP(MU_2 + ETA(2))
IF(CAT.EQ.3) CL = EXP(MU_3 + ETA(3))
With an omega statement:
$OMEGA BLOCK(1) 0.1
$OMEGA BLOCK(1) SAME
$OMEGA BLOCK(1) SAME
where I force the omega element corresponding to ETA1, ETA2 and ETA3 to be the
same.
Is this a valid approach to obtain what I need?
Or is there a simpler way in the mu-referencing framework to link different
thetas to the same omega element?
All the best,
Jacob
________________________________
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Link different thetas to same omega using mu referencing
This looks like it would work - it seems to obey the rules around
mu-referencing. You can simplify the $OMEGA by using SAME(3)
Mike
Michael J. Fossler, Pharm. D., Ph. D., F.C.P.
VP, Quantitative Sciences
Trevena, Inc
[email protected]<mailto:[email protected]>
Office: 610-354-8840, ext. 249
Cell: 610-329-6636
Quoted reply history
From: [email protected] [mailto:[email protected]] On
Behalf Of Leander, Jacob
Sent: Wednesday, April 13, 2016 7:01 AM
To: [email protected]
Subject: [NMusers] Link different thetas to same omega using mu referencing
Hi
Consider the case where we have a categorical (potentially time-varying)
covariate named CAT that can take several values (e.g. 0,1,2,3).
Let's say I want to model CL depending on this categorical covariate (where
parameters are estimated on log-scale).
A simple solution to this would be
IF(CAT.EQ.1) TVCL = THETA(1)
IF(CAT.EQ.2) TVCL = THETA(2)
IF(CAT.EQ.3) TVCL = THETA(3)
I let CL be described by a log-normal distribution with the same omega element
for all CAT values.
CL = EXP(TVCL + ETA(1))
With an omega statement:
$OMEGA 0.1
I now want to switch to the mu referencing framework in NONMEM. Each theta
needs to be reference to a MU value, and to force it to be described by the
same eta I apply the following approach.
MU_1 = THETA(1)
MU_2 = THETA(2)
MU_3 = THETA(3)
IF(CAT.EQ.1) CL = EXP(MU_1 + ETA(1))
IF(CAT.EQ.2) CL = EXP(MU_2 + ETA(2))
IF(CAT.EQ.3) CL = EXP(MU_3 + ETA(3))
With an omega statement:
$OMEGA BLOCK(1) 0.1
$OMEGA BLOCK(1) SAME
$OMEGA BLOCK(1) SAME
where I force the omega element corresponding to ETA1, ETA2 and ETA3 to be the
same.
Is this a valid approach to obtain what I need?
Or is there a simpler way in the mu-referencing framework to link different
thetas to the same omega element?
All the best,
Jacob
________________________________
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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,
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________________________________
Notice: This e-mail message, together with any attachments, contains
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legally privileged.
It is intended solely for use by the individual or entity named on this
message. If you are not the intended recipient, and have received this message
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Hi Jacob,
I suggest:
CAT1=0
CAT2=0
CAT3=0
IF(CAT.EQ.1) CAT1=1
IF(CAT.EQ.2) CAT2=1
IF(CAT.EQ.3) CAT3=1
MU_1 = CAT1*THETA(1) + CAT2*THETA(2) + CAT3*THETA(3)
CL = EXP(MU_1+ETA(1))
That way you have only one OMEGA. This could be more flexible when expanding
OMEGA for additional IIV in block format.
Cheers... Brian
Quoted reply history
From: [email protected] [mailto:[email protected]] On
Behalf Of Michael Fossler
Sent: Wednesday, April 13, 2016 7:56 AM
To: Leander, Jacob; [email protected]
Subject: [NMusers] RE: Link different thetas to same omega using mu referencing
This looks like it would work - it seems to obey the rules around
mu-referencing. You can simplify the $OMEGA by using SAME(3)
Mike
Michael J. Fossler, Pharm. D., Ph. D., F.C.P.
VP, Quantitative Sciences
Trevena, Inc
[email protected]<mailto:[email protected]>
Office: 610-354-8840, ext. 249
Cell: 610-329-6636
From: [email protected]<mailto:[email protected]>
[mailto:[email protected]] On Behalf Of Leander, Jacob
Sent: Wednesday, April 13, 2016 7:01 AM
To: [email protected]<mailto:[email protected]>
Subject: [NMusers] Link different thetas to same omega using mu referencing
Hi
Consider the case where we have a categorical (potentially time-varying)
covariate named CAT that can take several values (e.g. 0,1,2,3).
Let's say I want to model CL depending on this categorical covariate (where
parameters are estimated on log-scale).
A simple solution to this would be
IF(CAT.EQ.1) TVCL = THETA(1)
IF(CAT.EQ.2) TVCL = THETA(2)
IF(CAT.EQ.3) TVCL = THETA(3)
I let CL be described by a log-normal distribution with the same omega element
for all CAT values.
CL = EXP(TVCL + ETA(1))
With an omega statement:
$OMEGA 0.1
I now want to switch to the mu referencing framework in NONMEM. Each theta
needs to be reference to a MU value, and to force it to be described by the
same eta I apply the following approach.
MU_1 = THETA(1)
MU_2 = THETA(2)
MU_3 = THETA(3)
IF(CAT.EQ.1) CL = EXP(MU_1 + ETA(1))
IF(CAT.EQ.2) CL = EXP(MU_2 + ETA(2))
IF(CAT.EQ.3) CL = EXP(MU_3 + ETA(3))
With an omega statement:
$OMEGA BLOCK(1) 0.1
$OMEGA BLOCK(1) SAME
$OMEGA BLOCK(1) SAME
where I force the omega element corresponding to ETA1, ETA2 and ETA3 to be the
same.
Is this a valid approach to obtain what I need?
Or is there a simpler way in the mu-referencing framework to link different
thetas to the same omega element?
All the best,
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.
________________________________
Notice: This e-mail message, together with any attachments, contains
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USA. This information may be confidential, proprietary, copyrighted and/or
legally privileged.
It is intended solely for use by 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 and delete it and any attachments from
your system.
I’m not sure that Brian’s suggestion is acceptable due to the following
constraint I quote from one of the NONMEM manuals:
“Time dependent covariates cannot be part of the MU_ equation”
If CAT is time-varying (as suggested by Jacob) then “MU_1 = CAT1*THETA(1) +
CAT2*THETA(2) + CAT3*THETA(3)” includes time dependent covariates. Rather
worryingly, I don’t think NONMEM will trap this problem since I have fallen
foul of it with no resulting NONMEM warnings, and I have no idea what the
consequences are for the resulting NONMEM run and results.
Rupert
Rupert Austin, PhD
Senior Scientist
BAST Inc Limited
Loughborough University Science and Enterprise Park
Charnwood Wing
Holywell Park
Ashby Road
Loughborough, LE11 3AQ, UK
Tel: +44 (0)1509 222908
Quoted reply history
From: [email protected] [mailto:[email protected]] On
Behalf Of Sadler, Brian
Sent: 13 April 2016 13:26
To: [email protected]
Subject: [NMusers] RE: Link different thetas to same omega using mu referencing
Hi Jacob,
I suggest:
CAT1=0
CAT2=0
CAT3=0
IF(CAT.EQ.1) CAT1=1
IF(CAT.EQ.2) CAT2=1
IF(CAT.EQ.3) CAT3=1
MU_1 = CAT1*THETA(1) + CAT2*THETA(2) + CAT3*THETA(3)
CL = EXP(MU_1+ETA(1))
That way you have only one OMEGA. This could be more flexible when expanding
OMEGA for additional IIV in block format.
Cheers… Brian
From: [email protected] <mailto:[email protected]>
[mailto:[email protected]] On Behalf Of Michael Fossler
Sent: Wednesday, April 13, 2016 7:56 AM
To: Leander, Jacob; [email protected] <mailto:[email protected]>
Subject: [NMusers] RE: Link different thetas to same omega using mu referencing
This looks like it would work – it seems to obey the rules around
mu-referencing. You can simplify the $OMEGA by using SAME(3)
Mike
Michael J. Fossler, Pharm. D., Ph. D., F.C.P.
VP, Quantitative Sciences
Trevena, Inc
<mailto:[email protected]> [email protected]
Office: 610-354-8840, ext. 249
Cell: 610-329-6636
From: [email protected] <mailto:[email protected]>
[mailto:[email protected]] On Behalf Of Leander, Jacob
Sent: Wednesday, April 13, 2016 7:01 AM
To: [email protected] <mailto:[email protected]>
Subject: [NMusers] Link different thetas to same omega using mu referencing
Hi
Consider the case where we have a categorical (potentially time-varying)
covariate named CAT that can take several values (e.g. 0,1,2,3).
Let’s say I want to model CL depending on this categorical covariate (where
parameters are estimated on log-scale).
A simple solution to this would be
IF(CAT.EQ.1) TVCL = THETA(1)
IF(CAT.EQ.2) TVCL = THETA(2)
IF(CAT.EQ.3) TVCL = THETA(3)
I let CL be described by a log-normal distribution with the same omega element
for all CAT values.
CL = EXP(TVCL + ETA(1))
With an omega statement:
$OMEGA 0.1
I now want to switch to the mu referencing framework in NONMEM. Each theta
needs to be reference to a MU value, and to force it to be described by the
same eta I apply the following approach.
MU_1 = THETA(1)
MU_2 = THETA(2)
MU_3 = THETA(3)
IF(CAT.EQ.1) CL = EXP(MU_1 + ETA(1))
IF(CAT.EQ.2) CL = EXP(MU_2 + ETA(2))
IF(CAT.EQ.3) CL = EXP(MU_3 + ETA(3))
With an omega statement:
$OMEGA BLOCK(1) 0.1
$OMEGA BLOCK(1) SAME
$OMEGA BLOCK(1) SAME
where I force the omega element corresponding to ETA1, ETA2 and ETA3 to be the
same.
Is this a valid approach to obtain what I need?
Or is there a simpler way in the mu-referencing framework to link different
thetas to the same omega element?
All the best,
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.
_____
Notice: This e-mail message, together with any attachments, contains
information of Trevena, Inc., 1018 West 8th Avenue, King of Prussia, PA 19406,
USA. This information may be confidential, proprietary, copyrighted and/or
legally privileged.
It is intended solely for use by 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 and delete it and any attachments from
your system.
Rupert, I believe at least in principle you are right (I am not sure of the
specifics for NONMEM but I am generally familiar with the implementation
challenges that time varying covariates pose for EM methods. ) The basic
problem is that mu-modeling works to speed up EM methods because the EM update
step can be
reduced to a simple linear regression that is very fast. This cannot be done
in the time varying case, so a much more computationally intensive update must
be used.
If the regression is done anyway in the time varying case, the results are not
necessarily correct.
Quoted reply history
From: [email protected] [mailto:[email protected]] On
Behalf Of Rupert Austin
Sent: Wednesday, April 13, 2016 11:44 AM
To: 'Sadler, Brian'; [email protected]
Subject: RE: [NMusers] RE: Link different thetas to same omega using mu
referencing
I’m not sure that Brian’s suggestion is acceptable due to the following
constraint I quote from one of the NONMEM manuals:
“Time dependent covariates cannot be part of the MU_ equation”
If CAT is time-varying (as suggested by Jacob) then “MU_1 = CAT1*THETA(1) +
CAT2*THETA(2) + CAT3*THETA(3)” includes time dependent covariates. Rather
worryingly, I don’t think NONMEM will trap this problem since I have fallen
foul of it with no resulting NONMEM warnings, and I have no idea what the
consequences are for the resulting NONMEM run and results.
Rupert
Rupert Austin, PhD
Senior Scientist
BAST Inc Limited
Loughborough University Science and Enterprise Park
Charnwood Wing
Holywell Park
Ashby Road
Loughborough, LE11 3AQ, UK
Tel: +44 (0)1509 222908
From: [email protected]<mailto:[email protected]>
[mailto:[email protected]] On Behalf Of Sadler, Brian
Sent: 13 April 2016 13:26
To: [email protected]<mailto:[email protected]>
Subject: [NMusers] RE: Link different thetas to same omega using mu referencing
Hi Jacob,
I suggest:
CAT1=0
CAT2=0
CAT3=0
IF(CAT.EQ.1) CAT1=1
IF(CAT.EQ.2) CAT2=1
IF(CAT.EQ.3) CAT3=1
MU_1 = CAT1*THETA(1) + CAT2*THETA(2) + CAT3*THETA(3)
CL = EXP(MU_1+ETA(1))
That way you have only one OMEGA. This could be more flexible when expanding
OMEGA for additional IIV in block format.
Cheers… Brian
From: [email protected]<mailto:[email protected]>
[mailto:[email protected]] On Behalf Of Michael Fossler
Sent: Wednesday, April 13, 2016 7:56 AM
To: Leander, Jacob; [email protected]<mailto:[email protected]>
Subject: [NMusers] RE: Link different thetas to same omega using mu referencing
This looks like it would work – it seems to obey the rules around
mu-referencing. You can simplify the $OMEGA by using SAME(3)
Mike
Michael J. Fossler, Pharm. D., Ph. D., F.C.P.
VP, Quantitative Sciences
Trevena, Inc
[email protected]<mailto:[email protected]>
Office: 610-354-8840, ext. 249
Cell: 610-329-6636
From: [email protected]<mailto:[email protected]>
[mailto:[email protected]] On Behalf Of Leander, Jacob
Sent: Wednesday, April 13, 2016 7:01 AM
To: [email protected]<mailto:[email protected]>
Subject: [NMusers] Link different thetas to same omega using mu referencing
Hi
Consider the case where we have a categorical (potentially time-varying)
covariate named CAT that can take several values (e.g. 0,1,2,3).
Let’s say I want to model CL depending on this categorical covariate (where
parameters are estimated on log-scale).
A simple solution to this would be
IF(CAT.EQ.1) TVCL = THETA(1)
IF(CAT.EQ.2) TVCL = THETA(2)
IF(CAT.EQ.3) TVCL = THETA(3)
I let CL be described by a log-normal distribution with the same omega element
for all CAT values.
CL = EXP(TVCL + ETA(1))
With an omega statement:
$OMEGA 0.1
I now want to switch to the mu referencing framework in NONMEM. Each theta
needs to be reference to a MU value, and to force it to be described by the
same eta I apply the following approach.
MU_1 = THETA(1)
MU_2 = THETA(2)
MU_3 = THETA(3)
IF(CAT.EQ.1) CL = EXP(MU_1 + ETA(1))
IF(CAT.EQ.2) CL = EXP(MU_2 + ETA(2))
IF(CAT.EQ.3) CL = EXP(MU_3 + ETA(3))
With an omega statement:
$OMEGA BLOCK(1) 0.1
$OMEGA BLOCK(1) SAME
$OMEGA BLOCK(1) SAME
where I force the omega element corresponding to ETA1, ETA2 and ETA3 to be the
same.
Is this a valid approach to obtain what I need?
Or is there a simpler way in the mu-referencing framework to link different
thetas to the same omega element?
All the best,
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.
________________________________
Notice: This e-mail message, together with any attachments, contains
information of Trevena, Inc., 1018 West 8th Avenue, King of Prussia, PA 19406,
USA. This information may be confidential, proprietary, copyrighted and/or
legally privileged.
It is intended solely for use by 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 and delete it and any attachments from
your system.
I think the following code should work:
IF(CAT.EQ.1) CLCOV = THETA(1)IF(CAT.EQ.2) CLCOV = THETA(2)IF(CAT.EQ.3) CLCOV =
THETA(3)MU_1 = THETA(4)
CL = EXP(MU_1+ETA(1))*(1+CLCOV)
$OMEGA BLOCK(1) 0.1
Mannie
Quoted reply history
From: Rupert Austin <[email protected]>
To: "'Sadler, Brian'" <[email protected]>; [email protected]
Sent: Wednesday, April 13, 2016 11:44 AM
Subject: RE: [NMusers] RE: Link different thetas to same omega using mu
referencing
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div.yiv7090570546WordSection1 {}#yiv7090570546 I’m not sure that Brian’s
suggestion is acceptable due to the following constraint I quote from one of
the NONMEM manuals: “Time dependent covariates cannot be part of the MU_
equation” If CAT is time-varying (as suggested by Jacob) then “MU_1 =
CAT1*THETA(1) + CAT2*THETA(2) + CAT3*THETA(3)” includes time dependent
covariates. Rather worryingly, I don’t think NONMEM will trap this problem
since I have fallen foul of it with no resulting NONMEM warnings, and I have no
idea what the consequences are for the resulting NONMEM run and results.
Rupert Rupert Austin, PhDSenior ScientistBAST Inc LimitedLoughborough
University Science and Enterprise ParkCharnwood WingHolywell ParkAshby
RoadLoughborough, LE11 3AQ, UKTel: +44 (0)1509 222908 From:
[email protected] [mailto:[email protected]] On Behalf Of
Sadler, Brian
Sent: 13 April 2016 13:26
To: [email protected]
Subject: [NMusers] RE: Link different thetas to same omega using mu referencing
Hi Jacob, I suggest:CAT1=0CAT2=0CAT3=0IF(CAT.EQ.1) CAT1=1IF(CAT.EQ.2)
CAT2=1IF(CAT.EQ.3) CAT3=1MU_1 = CAT1*THETA(1) + CAT2*THETA(2) + CAT3*THETA(3)CL
= EXP(MU_1+ETA(1)) That way you have only one OMEGA. This could be more
flexible when expanding OMEGA for additional IIV in block format. Cheers…
Brian From: [email protected]
[mailto:[email protected]] On Behalf Of Michael Fossler
Sent: Wednesday, April 13, 2016 7:56 AM
To: Leander, Jacob; [email protected]
Subject: [NMusers] RE: Link different thetas to same omega using mu referencing
This looks like it would work – it seems to obey the rules around
mu-referencing. You can simplify the $OMEGA by using SAME(3) MikeMichael J.
Fossler, Pharm. D., Ph. D., F.C.P.VP, Quantitative SciencesTrevena,
[email protected]: 610-354-8840, ext. 249Cell: 610-329-6636
From: [email protected] [mailto:[email protected]] On
Behalf Of Leander, Jacob
Sent: Wednesday, April 13, 2016 7:01 AM
To: [email protected]
Subject: [NMusers] Link different thetas to same omega using mu referencing Hi
Consider the case where we have a categorical (potentially time-varying)
covariate named CAT that can take several values (e.g. 0,1,2,3).Let’s say I
want to model CL depending on this categorical covariate (where parameters are
estimated on log-scale). A simple solution to this would be IF(CAT.EQ.1) TVCL
= THETA(1)IF(CAT.EQ.2) TVCL = THETA(2)IF(CAT.EQ.3) TVCL = THETA(3) I let CL be
described by a log-normal distribution with the same omega element for all CAT
values. CL = EXP(TVCL + ETA(1)) With an omega statement: $OMEGA 0.1 I now
want to switch to the mu referencing framework in NONMEM. Each theta needs to
be reference to a MU value, and to force it to be described by the same eta I
apply the following approach. MU_1 = THETA(1)MU_2 = THETA(2)MU_3 = THETA(3)
IF(CAT.EQ.1) CL = EXP(MU_1 + ETA(1))IF(CAT.EQ.2) CL = EXP(MU_2 +
ETA(2))IF(CAT.EQ.3) CL = EXP(MU_3 + ETA(3)) With an omega statement: $OMEGA
BLOCK(1) 0.1$OMEGA BLOCK(1) SAME$OMEGA BLOCK(1) SAME where I force the omega
element corresponding to ETA1, ETA2 and ETA3 to be the same. Is this a valid
approach to obtain what I need? Or is there a simpler way in the mu-referencing
framework to link different thetas to the same omega element? All the
best,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.
Notice: This e-mail message, together with any attachments, contains
information of Trevena, Inc., 1018 West 8th Avenue, King of Prussia, PA 19406,
USA. This information may be confidential, proprietary, copyrighted and/or
legally privileged.
It is intended solely for use by 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 and delete it and any attachments from
your system.
Thanks. You’re right. With my solution the eta is not constant for an
individual, instead it will vary for each value of the categorical covariate,
meaning that it is similar to IOV. With your solution we restrict only one eta
per individual not matter of the covariate value.
To exemplify this discussion one can think of two different oral formulations
with different absorption rate that are given in sequence. The question is then
if we would expect that a person who has “higher than normal” absorption rate
for the first formulation also would have a “higher than normal” absorption
rate for the second formulation. If the answer to that question is yes then one
should impose the restriction that you described.
//Jacob
Quoted reply history
From: Emmanuel Chigutsa [mailto:[email protected]]
Sent: den 13 april 2016 22:47
To: Leander, Jacob <[email protected]>;
[email protected]; 'Sadler, Brian' <[email protected]>;
[email protected]
Subject: Re: [NMusers] RE: Link different thetas to same omega using mu
referencing
Hi Jacob,
Yes, THETA(4) would represent the typical value (before exponentiation). In
summary, writing your covariate code after the definition of MU should
circumvent the time-varying problem. If you want everything on a log scale you
could try:
OCL=MU_1+ETA(1)
CL=EXP(OCL+CLCOV)
The issue with trying to use different etas for the different thetas as you had
was that only the variance (omega) was constrained to be same, but not
necessarily the same eta for each ID.
Mannie
________________________________
From: "Leander, Jacob"
<[email protected]<mailto:[email protected]>>
To: Emmanuel Chigutsa <[email protected]<mailto:[email protected]>>;
"[email protected]<mailto:[email protected]>"
<[email protected]<mailto:[email protected]>>; "'Sadler,
Brian'" <[email protected]<mailto:[email protected]>>;
"[email protected]<mailto:[email protected]>"
<[email protected]<mailto:[email protected]>>
Sent: Wednesday, April 13, 2016 2:00 PM
Subject: RE: [NMusers] RE: Link different thetas to same omega using mu
referencing
Thanks for the answers.
Just as Rupert pointed out it is not possible to model time-dependent
covariates in the MU expression. I am not sure what is happening if you do but
since the NONMEM manual explicitly tell you to avoid it you should not do it.
It seems that Mannies code instead uses a THETA(4) to model the “mean” value
and then use CLCOV to change the value for different covariates. Or what does
THETA(4) mean in your code Mannie? Remember that the problems was to impose
same omega element for different thetas depending on time-varying covariate and
also estimate all the parameters on a log scale.
//Jacob
From: [email protected]<mailto:[email protected]>
[mailto:[email protected]] On Behalf Of Emmanuel Chigutsa
Sent: den 13 april 2016 19:01
To: [email protected]<mailto:[email protected]>; 'Sadler,
Brian' <[email protected]<mailto:[email protected]>>;
[email protected]<mailto:[email protected]>
Subject: Re: [NMusers] RE: Link different thetas to same omega using mu
referencing
I think the following code should work:
IF(CAT.EQ.1) CLCOV = THETA(1)
IF(CAT.EQ.2) CLCOV = THETA(2)
IF(CAT.EQ.3) CLCOV = THETA(3)
MU_1 = THETA(4)
CL = EXP(MU_1+ETA(1))*(1+CLCOV)
$OMEGA BLOCK(1) 0.1
Mannie
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