
596 Spatial Point Patterns: Methodology and Applications with R
panels correspond to a test of CSRI, not to the more general hypothesis of independence between
components.
We can also defin e analog ues of Besag’s L-function (Section 7.3.3) and the pair correlation
function (Section 7.6). For any types i and j, the cross-type L-function is defined as
L
i j
(r) =
r
K
i j
(r)
π
. (14.30)
This transformation approximately stabilises the variance of the estimate when the process is Po is-
son, and also transforms the benchmark value K
i j
(r) =
π
r
2
to L
i j
(r) = r.
The cross-type pair correlatio n functio n is defin ed as
g
i j
(r) =
K
′
i j
(r)
2
π
r
(14.31)
where K
′
i j
(r) is the ...