Re: [NMusers] Logic Expression in $DATA: ACCEPT or IGNORE

2014-11-19 Thread Xinting Wang
Dear Katya and Bill, Thanks a lot for your suggestion. Multiple IGNORE, as suggested Katya, actually worked. Best Regards On 18 November 2014 17:24, Ekaterina Gibiansky wrote: > Hi Xinting, > > You can separate the condition into several statements. For example, if > you need to accept (A=1 O

Re: [NMusers] Genotype data missing in some individuals

2014-11-19 Thread Jeroen Elassaiss-Schaap
Dear SoJeong, First you might want to answer the question whether that phenotype is indeed important in your dataset. With the initial popPK model you could plot posthoc clearance against bodyweight and/or inspect the posthocs of clearance for evidence of multiple peaks in your distribution. Yo

RE: [NMusers] Genotype data missing in some individuals

2014-11-19 Thread Rekic, Dinko
Dear SoJeong, I agree with everything Jeroen proposed. In addition to that, you may want to code the subjects with missing genotype as genotype 99 (or something similar) and then estimate genotype as categorical covariate on CL. This approach is not elegant but it is quick and often useful for

Re: [NMusers] Genotype data missing in some individuals

2014-11-19 Thread Leonid Gibiansky
I would do mixture model only if there is a very large -several folds- difference in PK parameters for two genotypes. If the difference is comparable with the inter-subject variability within the genotype, I would introduce category "missing" to remove the effect of those subjects on covariate

RE: [NMusers] Genotype data missing in some individuals

2014-11-19 Thread Denney, William S.
Hi SoJeong, I agree with Leonid here on the value of the mixture model. With potentially subtle changes, mixture models can be very difficult. One way that I've had luck previously with a similar approach is to make "unknown genotype" a separate category and then to fit a parameter that is fr

RE: [NMusers] Genotype data missing in some individuals

2014-11-19 Thread Mats Karlsson
Hi, I would use: IF (GENOTYPE.EQ.1) GENE = THETA(1) IF (GENOTYPE.EQ.2) GENE = THETA(2) IF (GENOTYPE.EQ.-99.AND.MIXNUM.EQ.1) GENE = THETA(1) IF (GENOTYPE.EQ.-99.AND.MIXNUM.EQ.2) GENE = THETA(2) $MIX P(1)=THETA(3) P(2)=1-P(1) .. To handle THETA(3) there are different options If I believe th

RE: [NMusers] Genotype data missing in some individuals

2014-11-19 Thread Sebastian Frechen
Hey Bill & SoJeong, in your suggestion (Bill), you would estimate a fixed effect for the unknown genotype weighting between G1 and G2. But let's assume that the status "genotype unknown" is completely at random, so some are of type 1 and some are of type 2. Wouldn't it be possible to implement

[NMusers] A question about handling large-scale data

2014-11-19 Thread Liudongyang_hotmail
Hello All Nonmem Users, I am modeling intra-gastric H+ concentrations as PD biomarker, which varies from 10e-7 to 10e-1. I log-transformed original data and used "Y = LOG(IPRED)+EPS(1)" as log-linear error model firstly. The profile could be simulated well, but when I fitted data, error messa