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().
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 asnew_levels.- ...
One or more objects created by
split_level().
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().
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().
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)
)
)
#> $residential
#> new_level relativity
#> 1 flat 0.95
#> 2 house 1.05
#>
#> $commercial
#> new_level relativity
#> 1 shop 1.1
#> 2 office 0.9
#>
