This function is an older version of poped_optim
. Please use poped_optim
unless you have a specific reason to use this function instead.
Usage
poped_optimize(
poped.db,
ni = NULL,
xt = NULL,
model_switch = NULL,
x = NULL,
a = NULL,
bpop = NULL,
d = NULL,
maxxt = NULL,
minxt = NULL,
maxa = NULL,
mina = NULL,
fmf = 0,
dmf = 0,
trflag = TRUE,
opt_xt = poped.db$settings$optsw[2],
opt_a = poped.db$settings$optsw[4],
opt_x = poped.db$settings$optsw[3],
opt_samps = poped.db$settings$optsw[1],
opt_inds = poped.db$settings$optsw[5],
cfaxt = poped.db$settings$cfaxt,
cfaa = poped.db$settings$cfaa,
rsit = poped.db$settings$rsit,
rsit_output = poped.db$settings$rsit_output,
fim.calc.type = poped.db$settings$iFIMCalculationType,
ofv_calc_type = poped.db$settings$ofv_calc_type,
approx_type = poped.db$settings$iApproximationMethod,
bUseExchangeAlgorithm = poped.db$settings$bUseExchangeAlgorithm,
iter = 1,
d_switch = poped.db$settings$d_switch,
ED_samp_size = poped.db$settings$ED_samp_size,
bLHS = poped.db$settings$bLHS,
use_laplace = poped.db$settings$iEDCalculationType,
...
)
Arguments
- poped.db
A PopED database.
- ni
A vector of the number of samples in each group.
- xt
A matrix of sample times. Each row is a vector of sample times for a group.
- model_switch
A matrix that is the same size as xt, specifying which model each sample belongs to.
- x
A matrix for the discrete design variables. Each row is a group.
- a
A matrix of covariates. Each row is a group.
- bpop
Matrix defining the fixed effects, per row (row number = parameter_number) we should have:
column 1 the type of the distribution for E-family designs (0 = Fixed, 1 = Normal, 2 = Uniform, 3 = User Defined Distribution, 4 = lognormal and 5 = truncated normal)
column 2 defines the mean.
column 3 defines the variance of the distribution (or length of uniform distribution).
Can also just supply the parameter values as a vector
c()
if no uncertainty around the parameter value is to be used. The parameter order of 'bpop' is defined in the 'fg_fun' or 'fg_file'. If you use named arguments in 'bpop' then the order of this vector can be rearranged to match the 'fg_fun' or 'fg_file'. See `reorder_parameter_vectors`.- d
Matrix defining the diagonals of the IIV (same logic as for the fixed effects matrix bpop to define uncertainty). One can also just supply the parameter values as a
c()
. The parameter order of 'd' is defined in the 'fg_fun' or 'fg_file'. If you use named arguments in 'd' then the order of this vector can be rearranged to match the 'fg_fun' or 'fg_file'. See `reorder_parameter_vectors`.- maxxt
Matrix or single value defining the maximum value for each xt sample. If a single value is supplied then all xt values are given the same maximum value.
- minxt
Matrix or single value defining the minimum value for each xt sample. If a single value is supplied then all xt values are given the same minimum value
- maxa
Vector defining the max value for each covariate. If a single value is supplied then all a values are given the same max value
- mina
Vector defining the min value for each covariate. If a single value is supplied then all a values are given the same max value
- fmf
The initial value of the FIM. If set to zero then it is computed.
- dmf
The initial OFV. If set to zero then it is computed.
- trflag
Should the optimization be output to the screen and to a file?
- opt_xt
Should the sample times be optimized?
- opt_a
Should the continuous design variables be optimized?
- opt_x
Should the discrete design variables be optimized?
- opt_samps
Are the number of sample times per group being optimized?
- opt_inds
Are the number of individuals per group being optimized?
- cfaxt
First step factor for sample times
- cfaa
Stochastic Gradient search first step factor for covariates
- rsit
Number of Random search iterations
- rsit_output
Number of iterations in random search between screen output
- fim.calc.type
The method used for calculating the FIM. Potential values:
0 = Full FIM. No assumption that fixed and random effects are uncorrelated.
1 = Reduced FIM. Assume that there is no correlation in the FIM between the fixed and random effects, and set these elements in the FIM to zero.
2 = weighted models (placeholder).
3 = Not currently used.
4 = Reduced FIM and computing all derivatives with respect to the standard deviation of the residual unexplained variation (sqrt(SIGMA) in NONMEM). This matches what is done in PFIM, and assumes that the standard deviation of the residual unexplained variation is the estimated parameter (NOTE: NONMEM estimates the variance of the residual unexplained variation by default).
5 = Full FIM parameterized with A,B,C matrices & derivative of variance.
6 = Calculate one model switch at a time, good for large matrices.
7 = Reduced FIM parameterized with A,B,C matrices & derivative of variance.
- ofv_calc_type
OFV calculation type for FIM
1 = "D-optimality". Determinant of the FIM: det(FIM)
2 = "A-optimality". Inverse of the sum of the expected parameter variances: 1/trace_matrix(inv(FIM))
4 = "lnD-optimality". Natural logarithm of the determinant of the FIM: log(det(FIM))
6 = "Ds-optimality". Ratio of the Determinant of the FIM and the Determinant of the uninteresting rows and columns of the FIM: det(FIM)/det(FIM_u)
7 = Inverse of the sum of the expected parameter RSE: 1/sum(get_rse(FIM,poped.db,use_percent=FALSE))
- approx_type
Approximation method for model, 0=FO, 1=FOCE, 2=FOCEI, 3=FOI.
- bUseExchangeAlgorithm
Use Exchange algorithm (1=TRUE, 0=FALSE)
- iter
The number of iterations entered into the
blockheader_2
function.- d_switch
******START OF CRITERION SPECIFICATION OPTIONS**********
D-family design (1) or ED-family design (0) (with or without parameter uncertainty)
- ED_samp_size
Sample size for E-family sampling
- bLHS
How to sample from distributions in E-family calculations. 0=Random Sampling, 1=LatinHyperCube –
- use_laplace
Should the Laplace method be used in calculating the expectation of the OFV?
- ...
arguments passed to other functions. See
Doptim
.
Details
This function optimized the objective function. The function works for both discrete and continuous optimization variables. This function takes information from the PopED database supplied as an argument. The PopED database supplies information about the the model, parameters, design and methods to use. Some of the arguments coming from the PopED database can be overwritten; if they are supplied then they are used instead of the arguments from the PopED database.
References
M. Foracchia, A.C. Hooker, P. Vicini and A. Ruggeri, "PopED, a software fir optimal experimental design in population kinetics", Computer Methods and Programs in Biomedicine, 74, 2004.
J. Nyberg, S. Ueckert, E.A. Stroemberg, S. Hennig, M.O. Karlsson and A.C. Hooker, "PopED: An extended, parallelized, nonlinear mixed effects models optimal design tool", Computer Methods and Programs in Biomedicine, 108, 2012.
See also
Other Optimize:
Doptim()
,
LEDoptim()
,
RS_opt()
,
a_line_search()
,
bfgsb_min()
,
calc_autofocus()
,
calc_ofv_and_grad()
,
mfea()
,
optim_ARS()
,
optim_LS()
,
poped_optim()
,
poped_optim_1()
,
poped_optim_2()
,
poped_optim_3()
Examples
library(PopED)
############# START #################
## Create PopED database
## (warfarin model for optimization)
#####################################
## Warfarin example from software comparison in:
## Nyberg et al., "Methods and software tools for design evaluation
## for population pharmacokinetics-pharmacodynamics studies",
## Br. J. Clin. Pharm., 2014.
## Optimization using an additive + proportional reidual error
## to avoid sample times at very low concentrations (time 0 or very late samples).
## find the parameters that are needed to define from the structural model
ff.PK.1.comp.oral.sd.CL
#> function (model_switch, xt, parameters, poped.db)
#> {
#> with(as.list(parameters), {
#> y = xt
#> y = (DOSE * Favail * KA/(V * (KA - CL/V))) * (exp(-CL/V *
#> xt) - exp(-KA * xt))
#> return(list(y = y, poped.db = poped.db))
#> })
#> }
#> <bytecode: 0x557079188b38>
#> <environment: namespace:PopED>
## -- parameter definition function
## -- names match parameters in function ff
sfg <- function(x,a,bpop,b,bocc){
parameters=c(CL=bpop[1]*exp(b[1]),
V=bpop[2]*exp(b[2]),
KA=bpop[3]*exp(b[3]),
Favail=bpop[4],
DOSE=a[1])
return(parameters)
}
## -- Define initial design and design space
poped.db <- create.poped.database(ff_fun=ff.PK.1.comp.oral.sd.CL,
fg_fun=sfg,
fError_fun=feps.add.prop,
bpop=c(CL=0.15, V=8, KA=1.0, Favail=1),
notfixed_bpop=c(1,1,1,0),
d=c(CL=0.07, V=0.02, KA=0.6),
sigma=c(prop=0.01,add=0.25),
groupsize=32,
xt=c( 0.5,1,2,6,24,36,72,120),
minxt=0.01,
maxxt=120,
a=c(DOSE=70),
mina=c(DOSE=0.01),
maxa=c(DOSE=100))
############# END ###################
## Create PopED database
## (warfarin model for optimization)
#####################################
##############
# D-family Optimization
##############
# below are a number of ways to optimize the problem
# RS+SG+LS optimization of DOSE and sample times
# optimization with just a few iterations
# only to check that things are working
out_1 <- poped_optimize(poped.db,opt_a=TRUE,opt_xt=TRUE,
rsit=2,sgit=2,ls_step_size=2,
iter_max=1,out_file = "")
#> ===============================================================================
#> Initial design evaluation
#>
#> Initial OFV = 55.3964
#>
#> Initial design
#> expected relative standard error
#> (%RSE, rounded to nearest integer)
#> Parameter Values RSE_0
#> CL 0.15 5
#> V 8 3
#> KA 1 14
#> d_CL 0.07 30
#> d_V 0.02 37
#> d_KA 0.6 27
#> sig_prop 0.01 32
#> sig_add 0.25 26
#>
#> ==============================================================================
#> Optimization of design parameters
#>
#> * Optimize Sampling Schedule
#> * Optimize Covariates
#>
#> *******************************
#> Initial Value
#> OFV(mf) = 55.3964
#> *******************************
#>
#> RS - It. : 2 OFV : 55.3964
#>
#> *******************************
#> RS Results
#> OFV(mf) = 55.3964
#>
#> Optimized Sampling Schedule
#> Group 1: 0.5 1 2 6 24 36 72 120
#>
#> Optimized Covariates:
#> Group 1: 70
#>
#> *********************************
#>
#> Run time for random search: 0.02 seconds
#>
#> SG - It. : 1 OFV : 55.45 Diff. : 1
#> SG - It. : 2 OFV : 55.61 Diff. : 0.002799
#>
#> SG - Iteration 2 --------- FINAL -------------------------
#> Normalized gradient: Grad_xt(OFV)/OFV
#> -0.00262405729196299
#> -0.000132025609212243
#> 0.0049562882696737
#> -0.000109893316026729
#> -0.000341253164434824
#> 2.72645074812749e-05
#> 0.000160461661950708
#> 3.06020481312946e-05
#> xt opt:
#> 0.210318514650852
#> 0.950298514650852
#> 2.28968148534915
#> 5.71031851465085
#> 23.7103185146509
#> 36.2896814853491
#> 72.2896814853491
#> 120
#> Normalized gradient: Grad_a(OFV)/OFV
#> 6.312896e-04
#> aopt:
#> 7.024140e+01
#> OFV(mf) : 55.6095
#> diff : 0.00279928
#> *************************************************************
#> Stochastic gradient run time: 0.326 seconds
#>
#> *****************************
#> Line Search
#>
#> Searching xt2 on group 1
#> Searching xt4 on group 1
#> Searching xt1 on group 1
#> group 1 -- xt[1] changed from 0.210319 to 0.01
#> OFV(MF) changed from 55.6095 to 55.8352
#> group 1 -- xt[1] changed from 0.01 to 120
#> OFV(MF) changed from 55.8352 to 55.8915
#> Searching xt6 on group 1
#> group 1 -- xt[6] changed from 36.2897 to 0.01
#> OFV(MF) changed from 55.8915 to 55.9642
#> group 1 -- xt[6] changed from 0.01 to 120
#> OFV(MF) changed from 55.9642 to 56.0271
#> Searching xt3 on group 1
#> Searching xt7 on group 1
#> group 1 -- xt[7] changed from 72.2897 to 120
#> OFV(MF) changed from 56.0271 to 56.0561
#> Searching xt5 on group 1
#> Searching xt8 on group 1
#> OFV(MF): 56.0561
#>
#> Best value for OFV(MF) = 56.0561
#>
#> Best value for xt:
#> Group 1: 0.9503 2.29 5.71 23.71 120 120 120 120
#>
#> Searching a1 on individual/group 1
#> group 1 -- a[1] changed from 70.2414 to 100
#> OFV(MF) changed from 56.0561 to 56.8149
#> OFV(MF): 56.8149
#> Best value for OFV(MF) = 56.8149
#>
#> Best value for a:
#> Group 1: 100 [0.01,100]
#>
#>
#> Line search run time: 0.19 seconds
#> ***************************
#>
#> ===============================================================================
#> FINAL RESULTS
#> Optimized Sampling Schedule
#> Group 1: 0.9503 2.29 5.71 23.71 120 120 120 120
#>
#> Optimized Covariates:
#> Group 1: 100
#>
#> OFV = 56.8149
#>
#> Efficiency:
#> ((exp(ofv_final) / exp(ofv_init))^(1/n_parameters)) = 1.194
#>
#> Expected relative standard error
#> (%RSE, rounded to nearest integer):
#> Parameter Values RSE_0 RSE
#> CL 0.15 5 5
#> V 8 3 3
#> KA 1 14 14
#> d_CL 0.07 0 0
#> d_V 0.02 37 34
#> d_KA 0.6 0 0
#> sig_prop 0.01 32 24
#> sig_add 0.25 26 16
#>
#> Total running time: 0.537 seconds
if (FALSE) { # \dontrun{
# RS+SG+LS optimization of sample times
# (longer run time than above but more likely to reach a maximum)
output <- poped_optimize(poped.db,opt_xt=T)
get_rse(output$fmf,output$poped.db)
plot_model_prediction(output$poped.db)
# MFEA optimization with only integer times allowed
mfea.output <- poped_optimize(poped.db,opt_xt=1,
bUseExchangeAlgorithm=1,
EAStepSize=1)
get_rse(mfea.output$fmf,mfea.output$poped.db)
plot_model_prediction(mfea.output$poped.db)
# Examine efficiency of sampling windows
plot_efficiency_of_windows(mfea.output$poped.db,xt_windows=0.5)
plot_efficiency_of_windows(mfea.output$poped.db,xt_windows=1)
# Random search (just a few samples here)
rs.output <- poped_optimize(poped.db,opt_xt=1,opt_a=1,rsit=20,
bUseRandomSearch= 1,
bUseStochasticGradient = 0,
bUseBFGSMinimizer = 0,
bUseLineSearch = 0)
get_rse(rs.output$fmf,rs.output$poped.db)
# line search, DOSE and sample time optimization
ls.output <- poped_optimize(poped.db,opt_xt=1,opt_a=1,
bUseRandomSearch= 0,
bUseStochasticGradient = 0,
bUseBFGSMinimizer = 0,
bUseLineSearch = 1,
ls_step_size=10)
# Stochastic gradient search, DOSE and sample time optimization
sg.output <- poped_optimize(poped.db,opt_xt=1,opt_a=1,
bUseRandomSearch= 0,
bUseStochasticGradient = 1,
bUseBFGSMinimizer = 0,
bUseLineSearch = 0,
sgit=20)
# BFGS search, DOSE and sample time optimization
bfgs.output <- poped_optimize(poped.db,opt_xt=1,opt_a=1,
bUseRandomSearch= 0,
bUseStochasticGradient = 0,
bUseBFGSMinimizer = 1,
bUseLineSearch = 0)
##############
# E-family Optimization
##############
# Adding 10% log-normal Uncertainty to fixed effects (not Favail)
bpop_vals <- c(CL=0.15, V=8, KA=1.0, Favail=1)
bpop_vals_ed_ln <- cbind(ones(length(bpop_vals),1)*4, # log-normal distribution
bpop_vals,
ones(length(bpop_vals),1)*(bpop_vals*0.1)^2) # 10% of bpop value
bpop_vals_ed_ln["Favail",] <- c(0,1,0)
bpop_vals_ed_ln
## -- Define initial design and design space
poped.db <- create.poped.database(
ff_fun=ff.PK.1.comp.oral.sd.CL,
fg_fun=sfg,
fError_fun=feps.add.prop,
bpop=bpop_vals_ed_ln,
notfixed_bpop=c(1,1,1,0),
d=c(CL=0.07, V=0.02, KA=0.6),
sigma=c(0.01,0.25),
groupsize=32,
xt=c( 0.5,1,2,6,24,36,72,120),
minxt=0,
maxxt=120,
a=70,
mina=0,
maxa=100)
# ED optimization using Random search (just a few samples here)
output <- poped_optimize(poped.db,opt_xt=1,opt_a=1,rsit=10,d_switch=0)
get_rse(output$fmf,output$poped.db)
# ED with laplace approximation,
# optimization using Random search (just a few samples here)
output <- poped_optimize(poped.db,opt_xt=1,opt_a=1,rsit=10,
d_switch=0,use_laplace=TRUE,laplace.fim=TRUE)
get_rse(output$fmf,output$poped.db)
} # }