In order to estimate biovailabilty in a PML model you can add the following code to the dosepoint of the absorption compartment dosepoint(Aa, bioavail = F) and then deifne the parameter F and its initial values stparm(F = …) fixef (F= c(0,0.5,1))
I’ll add to this topic. If you want to have a random effect on bioavailability, you’ll want to limit the support of the structural parameter to values between (but not including) zero and one, like this: stparm( F = ilogit( tvpF + npF) ) fixef( tvpF = 0) #some initial value ranef(…,npF,…) = … ilogit is the inverse logit function, or logistic function. I use the “p” in my variables to remind myself that these values undergo a logistic transformation.