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| SIMULATION_3 EXAMPLE |
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This is an example of simulation and estimation within the same NONMEM
run. It is a continuation of Simulation Example 2.
As in Simulation Example 2, values of the covariate WT are simulated
during the Simulation Step. They also replace the original WT values
in NONMEM's internal copy of the data set. This transgeneration makes
them available in the Estimation and Table Steps.
There are two models for V, illustrating the use of diferent models in
the Simulation and Estimation Steps:
(simulated V) VS = THETA(2) * EXP(ETA(3))
(non-simulated V) VN = THETA(3) + ETA(4)
There are two epsilons in the $ERROR block, illustrating the use of an
of using an initial estimate for estimation different from the value
used to simulate.
Because theta(2), eta(2), eta(3) and eps(1) are used only in the Simu-
lation Step, the FIXED attribute is specified for theta(2),
omega(2,2), omega(3,3) and sigma(1,1) during the Estimation Step.
$PROBLEM Simulation of population data w/ covariates
$INPUT ID TIME WT AMT DV
$DATA SIMORIG IGNORE=#
$SUBROUTINE ADVAN1
$PK
IF (ICALL.EQ.4) THEN
WT=70+70*ETA(3)
ENDIF
CL=THETA(1)*WT*EXP(ETA(1))
IF (ICALL.EQ.4) THEN
V=THETA(2)*EXP(ETA(2)) ; Simulated V
ELSE
V=THETA(3)+ETA(4) ; Non-simulated V
ENDIF
K=CL/V
S1=V
$ERROR
IF (ICALL.EQ.4) THEN
Y=F+F*EPS(1)
ELSE
Y=F+F*EPS(2)
ENDIF
$THETA (0,.0625) (10 FIX) (0,12)
$OMEGA .09 (.05 FIX) (.04 FIX) 4
$SIGMA (.01 FIX) .03
$SIMULATION (9215690) SUBPROBLEMS=10
$ESTIMATION
$TABLE ID TIME WT AMT NOPRINT FILE=SIMDATA3 NOHEADER
REFERENCES: Guide IV Section III.B.13, IV.I
REFERENCES: Guide V Section 12.4.8
REFERENCES: Guide VI Section III.C, III.E, IV.B, IV.G.1
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