Generate hierarchical models

Generates all hierarchical models satisfying specified criteria. The user can specify the number of lists, the maximum order of models to be considered, and (optionally) a data set for which any masked sparse interactions will not be included in the models. Intercept and main effects are always included.

Usage

get_hierarchical_models(
  nlists,
  maxorder = nlists - 1L,
  xdata = NULL,
  maxmodel = 100000L
)

Arguments

nlists

Number of lists (an integer from 2 to 9).

maxorder

Maximum interaction order; Inf permits all orders.

xdata

Optional capture history data. If supplied, models including masked sparse interactions for this data set will not be included. Minimal sparse interactions remain eligible.

maxmodel

Maximum number of models to be generated. If exceeded, the maximum order will be reduced, if necessary as far as 1, to bring the number of models below the specified limit.

Value

A named list of integer vectors specifying the hierarchical models. The name of each vector in the list is the hierarchy string representation of the model, and the vector itself is the vector of encoded capture histories included in the model. A capture history is encoded as the integer \(1 + \sum_{i \in S} 2^{i-1}\), where \(S\) is the set of capture lists in the history. The returned list has two attributes:

requested_maxorder

The value of maxorder supplied by the user, or its default value if omitted.

maxorder

The actual maximum interaction order of the generated models. This is capped at nlists and may be reduced further to satisfy maxmodel.

Examples

models <- get_hierarchical_models(3)
names(models)
#> [1] "[1,2,3]"    "[23,1]"     "[13,2]"     "[13,23]"    "[12,3]"    
#> [6] "[12,23]"    "[12,13]"    "[12,13,23]"
models[[1]]
#> [1] 1 2 3 5