From: Bill Gillespie <*bgillespiester*>

Date: Tue, 22 Dec 2015 14:24:36 -0500

Hi Bob,

Thanks for the reply. On investigating further I see this happens when

NONMEM reports a THETA value of 1.34+154 in the PRDERR file. Would I be

correct in thinking that is the result of a floating point error somewhere

in the sampling process?

Thanks,

Bill

On Tue, Dec 22, 2015 at 12:40 PM, Bauer, Robert <Robert.Bauer

wrote:

*> Bill:
*

*>
*

*> I just tested this on a simple script (see below), and the boundaries are
*

*> imposed in BAYES analysis for me.
*

*>
*

*>
*

*>
*

*> $PROB RUN# Example 1 (from samp5l)
*

*>
*

*> $INPUT C SET ID JID TIME DV=CONC AMT=DOSE RATE EVID MDV CMT CLX V1X QX
*

*> V2X SDIX SDSX
*

*>
*

*> $DATA example1.csv IGNORE=C
*

*>
*

*> $SUBROUTINES ADVAN3 TRANS4
*

*>
*

*> $PK
*

*>
*

*> MU_1=THETA(1)
*

*>
*

*> MU_2=THETA(2)
*

*>
*

*> MU_3=THETA(3)
*

*>
*

*> MU_4=THETA(4)
*

*>
*

*> IF (THETA(1)<1.63.OR.THETA(1)>1.8) WRITE(50,*) THETA(1)
*

*>
*

*> CL=DEXP(THETA(1)+ETA(1))
*

*>
*

*> V1=DEXP(THETA(2)+ETA(2))
*

*>
*

*> Q=DEXP(MU_3+ETA(3))
*

*>
*

*> V2=DEXP(MU_4+ETA(4))
*

*>
*

*> S1=V1
*

*>
*

*> $ERROR
*

*>
*

*> Y = F + F*EPS(1)
*

*>
*

*> $THETA (1.63, 1.67,1.8) 2.0 2.0 2.0
*

*>
*

*> $OMEGA BLOCK(4) VALUES(0.15,0.01)
*

*>
*

*> $SIGMA (0.6 )
*

*>
*

*> $PRIOR NWPRI
*

*>
*

*> $THETAP (2.0 FIX) (2.0 FIX) (2.0 FIX) (2.0 FIX)
*

*>
*

*> $THETAPV BLOCK(4) FIX VALUES(10000,0.0)
*

*>
*

*> $OMEGAP BLOCK(4) FIX VALUES(0.2,0.0)
*

*>
*

*> $OMEGAPD (4 FIX)
*

*>
*

*> $EST METHOD=BAYES INTERACTION NITER=1000 PRINT=100 CTYPE=3
*

*>
*

*> $COV MATRIX=R PRINT=E UNCONDITIONAL
*

*>
*

*>
*

*>
*

*> Robert J. Bauer, Ph.D.
*

*>
*

*> Vice President, Pharmacometrics R&D
*

*>
*

*> ICON Early Phase
*

*>
*

*> Office: (215) 616-6428
*

*>
*

*> Mobile: (925) 286-0769
*

*>
*

*> Robert.Bauer *

*>
*

*> www.iconplc.com
*

*>
*

*>
*

*>
*

*> *From:* owner-nmusers *

*> *On Behalf Of *Bill Gillespie
*

*> *Sent:* Tuesday, December 22, 2015 8:14 AM
*

*> *To:* nmusers *

*> *Subject:* [NMusers] BAYES method and initial estimate bounds
*

*>
*

*>
*

*>
*

*> Hi all,
*

*>
*

*>
*

*>
*

*> If bounds are specified in the $THETA statements for initial estimates,
*

*> what, if any, effect do they have when the BAYES method is used?
*

*>
*

*>
*

*>
*

*> I initially thought they might work in conjunction with the prior
*

*> specifications to implement truncated priors. However that does not seem to
*

*> be true because statements like "IF(ABS(THETA(1)) > 10) EXIT 1 14"
*

*> sometimes get tripped even when THETA(1) is bounded between -10 and 10 in
*

*> the $THETA statement.
*

*>
*

*>
*

*>
*

*> Happy Holidays,
*

*>
*

*> Bill
*

*>
*

*>
*

*> ICON plc made the following annotations.
*

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Received on Tue Dec 22 2015 - 14:24:36 EST

Date: Tue, 22 Dec 2015 14:24:36 -0500

Hi Bob,

Thanks for the reply. On investigating further I see this happens when

NONMEM reports a THETA value of 1.34+154 in the PRDERR file. Would I be

correct in thinking that is the result of a floating point error somewhere

in the sampling process?

Thanks,

Bill

On Tue, Dec 22, 2015 at 12:40 PM, Bauer, Robert <Robert.Bauer

wrote:

Received on Tue Dec 22 2015 - 14:24:36 EST