Kmulti.ls {ecespa} | R Documentation |
Lotwick's and Silverman's combined estimator of the marked K-function
Description
For a multitype point pattern, calculates the combined estimator of the bivariate and
functions.
Usage
Kmulti.ls(X, I, J, r = NULL, corre = "isotropic")
Arguments
X |
Multitype marked point pattern. An object with the |
I |
Subset index specifying the points of the first pattern. |
J |
Subset index specifying the points of the second pattern. |
r |
Numeric vector. The values of the argument r at which the multitype K function |
corre |
A character item selecting any of the options "border", "bord.modif", "isotropic", "Ripley" or
"translate", as described in |
Details
As a consequence of edge effects, the estimators and
of the same bivariate pattern could differ.
is the combined estimator defined by Lotwick and Silverman (1982) as
and
being respectively the number of points in
and
.
Value
An object of class "fv" (see fv.object
). Essentially a data frame containing numeric columns
r |
The values of the argument r at which the function |
.
theo |
The theoretical value of |
.
together with a column or columns named "border", "bord.modif", "iso" and/or "trans", according to the selected edge corrections.
These columns contain estimates of the function obtained by the edge corrections named.
Note
Kmulti.ls
is a wrapper for a convenient use of the Kmulti
function of spatstat.
Please refer to its help page for additional documentation.
Author(s)
Marcelino de la Cruz
References
Lotwick,H.W. & Silverman, B. W. 1982. Methods for analysing spatial processes of several types of points. Journal of the Royal Statistical Society B, 44: 406-413. doi:10.1111/j.2517-6161.1982.tb01221.x.
Examples
data(amacrine)
plot(Kmulti.ls(amacrine, I=amacrine$marks=="on", J=amacrine$marks=="off",
corre="isotropic"), sqrt(./pi)-r~r, main="")
# compare with Kmulti
plot(Kmulti(amacrine, I=amacrine$marks=="on", J=amacrine$marks=="off"),
sqrt(iso/pi)-r~r, add=TRUE, col=3)
plot(Kmulti(amacrine, J=amacrine$marks=="on", I=amacrine$marks=="off"),
sqrt(iso/pi)-r~r, add=TRUE, col=4)