scan.zones {smerc}

Determine zones for the spatial scan test

Description

scan.zones determines the unique candidate zones to consider for the circular spatial scan test of Kulldorff (1997).

Usage

scan.zones(coords, pop, ubpop = 0.5, longlat = FALSE)

Arguments

coords

An n \times 2 matrix of centroid coordinates for the regions in the form (x, y) or (longitude, latitude) is using great circle distance.

pop

The population size associated with each region.

ubpop

The upperbound of the proportion of the total population to consider for a cluster.

longlat

The default is FALSE, which specifies that Euclidean distance should be used. If longlat is TRUE, then the great circle distance is used to calculate the intercentroid distance.

Value

Returns a list of zones to consider for clustering. Each element of the list contains a vector with the location ids of the regions in that zone.

Author(s)

Joshua French

References

Kulldorff, M. (1997) A spatial scan statistic. Communications in Statistics - Theory and Methods, 26(6): 1481-1496, <doi:10.1080/03610929708831995>

Examples

data(nydf)
coords <- cbind(nydf$longitude, nydf$latitude)
zones <- scan.zones(
  coords = coords, pop = nydf$pop,
  ubpop = 0.1, longlat = TRUE
)