ACO: A function to compute Absolute Concentration index (ACO)

Description

The absolute concentration index, ACO, computes the total area inhabited by a group, and compares the result to the minimum and maximum possible areas that could be inhabited by that group in the study area. The function can be used in two ways: to provide an area vector or a external geographic information source (spatial object or shape file).

Usage

ACO(x, a = NULL, spatobj = NULL, folder = NULL, shape = NULL)

Value

a numeric vector containing Absolute Concentration index value for each group

Arguments

x: - an object of class matrix (or which can be coerced to that class), where each column represents the distribution of a group within spatial units. The number of columns should be greater than 1 (at least 2 groups are required). You should not include a column with total population, because this will be interpreted as a group.
a: - a numeric vector containing spatial unit areas
spatobj: - a spatial object (SpatialPolygonsDataFrame) with geographic information
folder: - a character vector with the folder (directory) name indicating where the shapefile is located on the drive
shape: - a character vector with the name of the shapefile (without the .shp extension).

References

Massey D. S. and Denton N. A. (1988) The dimensions of residential segregation. Social Forces 67(2), pp. 281-315.

Examples

Run this code

x <- GreHSize@data[ ,3:5]
ar <- area(GreHSize)
foldername <- system.file('extdata', package = 'OasisR')
shapename <- 'GreHSize'

ACO(x, a = ar) 

ACO(x, spatobj = GreHSize)

ACO(x, folder = foldername, shape = shapename)