relativity_specification: Define sublevel relativity specifications

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Define sublevel relativity specifications

Description

Use split_level() to describe how one existing GLM factor level is divided into more detailed portfolio levels with specified multiplicative relativities. Use relativities() to combine one or more of these definitions into the specification supplied to add_relativities().

Usage

split_level(level, new_levels, relativities)

relativities(...)

Arguments

level	Character string. Existing level of the risk factor to split.
new_levels	Character vector. Levels of the more detailed portfolio variable within level.
relativities	Numeric vector. Multiplicative relativities corresponding to new_levels. Must have the same length as new_levels.
...	One or more objects created by split_level().

Details

level identifies the existing parent level in model_variable. new_levels identifies the corresponding levels of split_variable. relativities gives their relative tariff effects before any optional exposure normalisation by add_relativities().

Each call to split_level() represents one parent level. Several parent levels can be refined in one step by passing their definitions to relativities(). Parent levels must be unique within the combined specification. Levels of the original model variable that are not included remain unsplit.

These helpers assemble and validate explicit tariff assumptions. They do not estimate, normalise or apply the supplied relativities and do not alter a fitted GLM. Exposure normalisation, when requested, is performed by add_relativities().

Value

split_level() returns a named list of length one. Its name is level; its value is a data frame with columns new_level and relativity. relativities() returns the combined named list expected by the relativities argument of add_relativities().

Author(s)

Martin Haringa

See Also

add_relativities()

Examples

construction_split <- split_level(
  level = "residential",
  new_levels = c("flat", "house"),
  relativities = c(0.95, 1.05)
)

relativities(
  construction_split,
  split_level(
    "commercial",
    new_levels = c("shop", "office"),
    relativities = c(1.10, 0.90)
  )
)

insurancerating documentation built on Sept. 1, 2026, 5:08 p.m.