Pull a parameter estimate or its standard error by name

Description

Name-based accessors for fit$estimates. ferx_coef() returns the point estimate on the scale it was estimated on (thetas as declared - so on the log scale for a log-transformed theta; omega and kappa as variances); ferx_se() returns the matching standard error from the covariance step.

Usage

ferx_coef(fit, param = NULL)

ferx_se(fit, param = NULL)

Arguments

  • fit: A ferx_fit object from [ferx_fit](ferx_fit.qmd) (or [ferx_load_fit](ferx_load_fit.qmd)).
  • param: Character vector of parameter names, as they appear in the row names of fit$estimates: theta names ("TVCL"), eta names for the omega diagonal ("ETA_CL"), sigma names ("EPS_PROP") and kappa names for an IOV diagonal ("KAPPA_CL"). Unnamed parameters use the fallback labels "THETA1", "OMEGA(1,1)", "SIGMA(1)", "KAPPA1". A name declared in more than one block is qualified by that block - a CL declared as both a theta and an eta is addressed as "CL.theta" and "CL.omega", and the bare "CL" is an error rather than one of the two chosen silently. NULL (default) returns every parameter, in table order.

Details

Unlike fit$estimates[param, ], an unrecognised name is an error listing the closest available names, not a silent NA - a mistyped parameter cannot be mistaken for an unestimated one.

Seealso

fit$estimates for the full table (SE, relative standard error, confidence intervals, natural-scale back-transforms) and fit$cor_matrix for parameter correlations. Other fitting: [ferx_bootstrap](ferx_bootstrap.qmd), [ferx_bootstrap_summarize](ferx_bootstrap_summarize.qmd), [ferx_check_init](ferx_check_init.qmd), [ferx_collect](ferx_collect.qmd), [ferx_covariance](ferx_covariance.qmd), [ferx_fit](ferx_fit.qmd), [ferx_inits_from_nca](ferx_inits_from_nca.qmd), [ferx_sir](ferx_sir.qmd), [ferx_stop](ferx_stop.qmd), [print.ferx_job](ferx_fit_async.qmd)

Concept

fitting

Value

A named numeric vector, one element per requested name, in the order requested. For ferx_se(), NA where the covariance step did not run or produced no standard error for that parameter; a parameter declared FIX carries the engine’s exact 0, not NA.

Examples

ex  <- ferx_example("warfarin")
fit <- ferx_fit(ex$model, ex$data, method = "gn")
ferx_coef(fit)                     # every parameter
ferx_coef(fit, "TVCL")             # one theta
ferx_se(fit, c("TVCL", "TVV"))     # standard errors