oddsRatio {assignR}

Odds ratio of points or regions

Description

Calculate ratio of odds for two locations (points or polygons)

Usage

oddsRatio(pdR, inputP)

Arguments

pdR

SpatRaster of probability density maps, e.g., as produced by pdRaster.

inputP

SpatVector points object of length 1 or 2 or polygons object of length 2

Examples

library(terra)

# load hydrogen isotope data for human hair in North America
d = subOrigData(group = "Modern human", mask = naMap, genplot = FALSE)

# rescale from environmental isoscape to tissue isoscape
r = calRaster(d, d2h_lrNA, naMap, genplot = FALSE)

# four unknown-origin examples
id = c("A", "B", "C", "D")
d2H = c(-110, -90, -105, -102)
un = data.frame(id, d2H)

# posterior probabilities
pp = pdRaster(r, un, mask = naMap, genplot = FALSE)

# SpatialPolygons for two regions of interest
s1 = states[states$STATE_ABBR == "UT",]
s2 = states[states$STATE_ABBR == "NM",]
plot(naMap)
plot(s1, border = "red", add = TRUE)
plot(s2, border = "blue", add = TRUE)

# Get odds ratio for two regions using SpatialPolygon method
s12 = rbind(s1, s2)
oddsRatio(pp, s12)                     

# Create SpatialPoints for two points of interest
p1 = c(-112, 40)
p2 = c(-105, 33)
p12 = vect(rbind(p1, p2), crs = "WGS84")
points(p12, pch = 21, bg = "light blue")

# Get odds ratio for two points using SpatialPoints method
oddsRatio(pp, p12)