zones {SpatialEpi} | R Documentation |
Based on the population counts and centroid coordinates of each area, output the set of zones as defined by Kulldorff and other geographical information.
zones(geo, area.population, pop.upper.bound)
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 |
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 |
Albert Y. Kim
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.
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)