Compresses a data matrix based on mutual information (segregation)

Given a data set that identifies suitable neighbors for merging, this function will merge units iteratively, where in each iteration the neighbors with the smallest reduction in terms of total M will be merged.

Usage

compress(
  data,
  group,
  unit,
  weight = NULL,
  neighbors = "local",
  n_neighbors = 50,
  max_iter = Inf
)

Arguments

data

A data frame.

group

A categorical variable contained in data. Defines the first dimension over which segregation is computed.

unit

A categorical variable contained in data. Defines the second dimension over which segregation is computed.

weight

Numeric. Only frequency weights are allowed. (Default NULL)

neighbors

Either a data frame or a character. If data frame, then it needs exactly two columns, where each row identifies a set of "neighbors" that may be merged. If "local", considers the n_neighbors closest neighbors in terms of local segregation. If "all", all units are considered as possible neighbors. This may be very time-consuming.

n_neighbors

Only relevant if neighbors is "local".

max_iter

Maximum number of iterations (Default Inf)

Value

Returns a data.table.