Analysing spatial point patterns in R - CSIRO

31.3 Distance methods and summary functions 193
array of G functions for lansing.
hickory
maple
Gcrosshickory, hickory(r)
0.0 0.2 0.4 0.6 0.8
Gcrosshickory, maple(r)
0.0 0.2 0.4 0.6 0.8
0.000 0.005 0.010 0.015 0.020 0.025 0.030
r (one unit = 924 feet)
0.000 0.005 0.010 0.015 0.020 0.025 0.030
r (one unit = 924 feet)
maple
Gcrossmaple, hickory(r)
0.0 0.2 0.4 0.6 0.8
Gcrossmaple, maple(r)
0.0 0.2 0.4 0.6 0.8
hickory
0.000 0.005 0.010 0.015 0.020 0.025 0.030
r (one unit = 924 feet)
0.000 0.005 0.010 0.015 0.020 0.025 0.030
r (one unit = 924 feet)
31.3.3 One type to any type
Also defined are the “i-to-any” summaries
G i• (r), the distribution function of the distance from a point of type i to the nearest other
point of any type;
K i• (r) is 1/λ times the expected number of points of any type within a distance r of a
typical point of type i. Here λ = ∑ j λ j is the intensity of the entire process X.
L i• (r) is the corresponding L-function
√
Ki• (r)
L i• (r) = .
π
g i• (r) is the corresponding analogue of the pair correlation function
g i• (r) = K′ i• (r)
2πr .
J i• is defined by
J i• (r) = 1 − G i•
1 − F(r)
These are computing by Gdot,Kdot, Ldot,pcfdot andJdot respectively, or using alltypes.
> plot(Gdot(amacrine, "on"))
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