smerc (version 1.8.3)

elliptic.nn: Nearest neighbors for elliptic scan

Description

elliptic.nn computes the nearest neighbors relationships for elliptic.test. It will provide a list of nearest neighbors, and a list of the associated shape and angle.

Usage

elliptic.nn(
  coords,
  pop,
  ubpop = 0.5,
  shape = c(1, 1.5, 2, 3, 4, 5),
  nangle = c(1, 4, 6, 9, 12, 15)
)

Value

A list of nested nearest neighbors, the associated shapes and angles for each set of nn, and all of the shapes and angles you get for each zone constructed from the set of nearest neighbors.

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.

shape

The ratios of the major and minor axes of the desired ellipses.

nangle

The number of angles (between 0 and 180) to consider for each shape.

Examples

data(nydf)
coords <- with(nydf, cbind(longitude, latitude))
enn <- elliptic.nn(coords, nydf$pop, 0.1,
  shape = c(1, 1.5), nangle = c(1, 4)
)