getsigma: Compute overall residual variability from elimination phase

In nlmixr2autoinit: Automatic Generation of Initial Estimates for Population Pharmacokinetic Modeling

Compute overall residual variability from elimination phase

Description

Applies getsigmas to each individual and dose group after filtering observation records (EVID == 0), and calculates trimmed mean estimates of additive and proportional residual variability.

Usage

getsigma(df, nlastpoints = 3, sigma_trim = 0.05)

Arguments

df	Full pharmacokinetic dataset containing at least the columns: EVID, ID, TIME, DV, and routeobs.
nlastpoints	Number of terminal points used for elimination phase regression in each group (passed to getsigmas).
sigma_trim	Trimming proportion used when calculating trimmed means of residual standard deviations. Default is 0.05.

Details

The function groups the dataset by subject and dose occasion, applies elimination-phase residual analysis using getsigmas, and summarizes the individual residual standard deviations by their trimmed means. This provides population-level estimates of additive and proportional residual unexplained variability (RUV).

Value

A list containing:

• summary: Named list with trimmed mean values of additive and proportional residual variability

• full: Data frame with residual estimates for each individual-dose group

Author(s)

Zhonghui Huang

See Also

getsigmas

Examples

dat <- Bolus_1CPT
dat <- processData(dat)$dat
getsigma(dat)

nlmixr2autoinit documentation built on Nov. 14, 2025, 1:07 a.m.