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5.6 Volume of intersection index

Volume of intersection under the full UDs of 2 animals (Millspaugh et al. 2000, Seidel 1992). Values range from zero (no overlap) to 1 (identical UDs).

kerneloverlaphr(ud, meth="VI", conditional=TRUE)

            FP048           FP094      FP110          FP113        FP121       FP128
FP048 0.9482742 0.0000000 0.0000000 0.0000000 0.0000000 0.0000000
FP094 0.0000000 0.9487819 0.0000000 0.0000000 0.0000000 0.0000000
FP110 0.0000000 0.0000000 0.9480843 0.0000000 0.0000000 0.0000000
FP113 0.0000000 0.0000000 0.0000000 0.9461914 0.0000000 0.0000000
FP121 0.0000000 0.0000000 0.0000000 0.0000000 0.9435922 0.1343167
FP128 0.0000000 0.0000000 0.0000000 0.0000000 0.1343167 0.9472716

#Plot out to visualize overlap
plot(idsp, col="yellow")
uds <- getverticeshr(ud)
plot(uds, add=TRUE)

plot(idsp, col="yellow")
ud1 <- getverticeshr(ud[[1]])
plot(ud1, add=TRUE)
ud2 <- getverticeshr(ud[[2]])
plot(ud2, lwd=2, add=TRUE)
ud3 <- getverticeshr(ud[[3]])
plot(ud3, lwd=3, add=TRUE)
ud4 <- getverticeshr(ud[[4]])
plot(ud4, lwd=4, add=TRUE)

#An alternative way with only the locations
kerneloverlap(idsp[,1], grid=200, method="HR", percent=95, conditional=TRUE)
kerneloverlap(idsp[,1], grid=200, method="PHR", percent=95, conditional=TRUE)
kerneloverlap(idsp[,1], grid=200, method="BA", percent=95, conditional=TRUE)
kerneloverlap(idsp[,1], grid=200, method="UDOI", percent=95, conditional=TRUE)
kerneloverlap(idsp[,1], grid=200, method="HD", percent=95, conditional=TRUE)
kerneloverlap(idsp[,1], grid=200, method="VI", percent=95, conditional=TRUE)