create_geo_objects: Create geographical objects to be used in Bayesian Cluster...

In SpatialEpi: Methods and Data for Spatial Epidemiology

Create geographical objects to be used in Bayesian Cluster Detection Method

Description

This internal function creates the geographical objects needed to run the Bayesian cluster detection method in bayes_cluster(). Specifically it creates all single zones based data objects, where single zones are the zones defined by Kulldorff (1997).

Usage

create_geo_objects(max.prop, population, centroids, sp.obj)

Arguments

max.prop	maximum proportion of study region's population each single zone can contain
population	vector of length n of the population of each area
centroids	n x 2 table of the (x,y)-coordinates of the area centroids. The coordinate system must be grid-based
sp.obj	object of class SpatialPolygons (See SpatialPolygons-class) representing the study region

Value

overlap	list with two elements: 1. presence which lists for each area all the single zones it is present in and 2. cluster.list for each single zone its component areas
cluster.coords	n.zones x 2 matrix of the center and radial area of each single zone

Author(s)

Albert Y. Kim

References

Wakefield J. and Kim A.Y. (2013) A Bayesian model for cluster detection.Biostatistics, 14, 752–765.

Examples

data(pennLC)
max.prop <- 0.15
population <- tapply(pennLC$data$population, pennLC$data$county, sum)
centroids <- latlong2grid(pennLC$geo[, 2:3])
sp.obj <- pennLC$spatial.polygon
output <- create_geo_objects(max.prop, population, centroids, sp.obj)
## number of single zones
nrow(output$cluster.coords)

SpatialEpi documentation built on March 7, 2023, 8 p.m.