prepare_refinement: Prepare a model refinement workflow

In insurancerating: Actuarial Tools for Insurance Pricing Models

Prepare a model refinement workflow

Description

Start a refinement workflow for a fitted GLM. Refinement steps such as smoothing, restrictions and expert-based relativities can be added sequentially and are only applied once refit() is called.

Usage

prepare_refinement(model, data = NULL)

Arguments

model	Object of class glm.
data	Optional data.frame containing exactly the observations retained in the fitted GLM and all required model variables. If model fitting omitted rows because of missing values, supply the retained model data rather than the original unfiltered data. If NULL, the data are retrieved from the model object.

Details

prepare_refinement() creates a persistent refinement specification. This object contains the original GLM, the corresponding model data and the ordered smoothing, restriction and relativity steps. It is the object that should be retained and edited during actuarial review.

refit() applies the stored specification and returns a fitted GLM for model diagnostics, prediction and tariff reporting. The returned GLM is a result, not an editable refinement specification. Functions such as add_smoothing(), edit_smoothing(), add_restriction() and add_relativities() therefore accept a rating_refinement object and do not accept an ordinary or refitted GLM directly.

A practical iterative workflow keeps both objects:

refinement <- prepare_refinement(model) |>
  add_smoothing(...)

fitted_model <- refit(refinement)

refinement <- refinement |>
  edit_smoothing(...)

fitted_model <- refit(refinement)

prepare_refinement() is normally required only once for such an iteration. Calling it on a model returned by refit() deliberately starts a new refinement workflow with the already refined model as its baseline; it does not recover the earlier smoothing or restriction steps for further editing.

Value

Object of class rating_refinement. Retain this object when refinement steps may need to be reviewed or edited after fitting.

See Also

add_smoothing(), edit_smoothing(), add_restriction(), add_relativities(), refit()

insurancerating documentation built on July 30, 2026, 5:09 p.m.