Then, we consider the other sources of error as a separate measure of intraindividual variability. This we call gamma, and we use it to scale the assay error polynomial. This is nonparametric, NOT noncompartmental. Please note the difference. Many still have confused these terms or used them interchengeably.
Nonparametric population modeling methods use structal models.
You get basically one set of parameter values for each patient you have studied, plus an estimate of the probability of each such set. It would be the exactly known parameter values for each subject studied. No statistical summaries can improve on this. Alain Mallet has shown this back in the eighties. You have N sets of parameter values.