zones {SpatialEpi}R Documentation

Create Set of All Zones and Output Geographical Information

Description

Based on the population counts and centroid coordinates of each area, output the set of zones as defined by Kulldorff and other geographical information.

Usage

zones(geo, area.population, pop.upper.bound)

Arguments

geo an n x 2 table of the (x,y)-coordinates of the area centroids
area.population a vector of population counts of each area
pop.upper.bound maximum proportion of study region each zone can contain

Value

A list containing

nearest.neighbors a list of n elements, where each element is a vector of the nearest neighbors in order of distance up until pop.upper.bound of the total population is attained
n.zones total number of zones
cluster.coords an n x 2 table of the center and the radial areas for each zone
dist an n x n inter-point distance matrix

Author(s)

Albert Y. Kim

References

Kulldorff, M. (1997) A spatial scan statistic. Communications in Statistics: Theory and Methods, 26, 1481–1496.

Kulldorff M. and Nagarwalla N. (1995) Spatial disease clusters: Detection and Inference. Statistics in Medicine, 14, 799–810.

Examples

data(pennLC)
geo <- pennLC$geo[,2:3]
geo <- latlong2grid(geo)
area.population <- tapply(pennLC$data$population, pennLC$data$county, sum)
pop.upper.bound <- 0.5

geo.info <- zones(geo, area.population, pop.upper.bound)

[Package SpatialEpi version 0.1 Index]