linearmarkconnect {spatstat.linnet}

Mark Connection Function for Multitype Point Pattern on Linear Network

Description

For a multitype point pattern on a linear network, estimate the mark connection function from points of type i to points of type j.

Usage

linearmarkconnect(X, i, j, r=NULL, ...)

Arguments

X

The observed point pattern, from which an estimate of the mark connection function p_{ij}(r) will be computed. An object of class "lpp" which must be a multitype point pattern (a marked point pattern whose marks are a factor).

i

Number or character string identifying the type (mark value) of the points in X from which distances are measured. Defaults to the first level of marks(X).

j

Number or character string identifying the type (mark value) of the points in X to which distances are measured. Defaults to the second level of marks(X).

r

numeric vector. The values of the argument r at which the function p_{ij}(r) should be evaluated. There is a sensible default. First-time users are strongly advised not to specify this argument. See below for important conditions on r.

...

Arguments passed to linearpcfcross and linearpcf.

Details

This is a counterpart of the function markconnect for a point pattern on a linear network (object of class "lpp").

The argument i will be interpreted as levels of the factor marks(X). If i is missing, it defaults to the first level of the marks factor.

The argument r is the vector of values for the distance r at which p_{ij}(r) should be evaluated. The values of r must be increasing nonnegative numbers and the maximum r value must not exceed the radius of the largest disc contained in the window.

Value

An object of class "fv" (see fv.object).

Warnings

The argument i is interpreted as a level of the factor marks(X). Beware of the usual trap with factors: numerical values are not interpreted in the same way as character values.

Author(s)

Adrian Baddeley [e-mail]

References

Baddeley, A, Jammalamadaka, A. and Nair, G. (2014) Multitype point process analysis of spines on the dendrite network of a neuron. Applied Statistics (Journal of the Royal Statistical Society, Series C), 63, 673–694.

See Also

linearpcfcross, linearpcf, linearmarkequal, markconnect.

Examples

   pab <- linearmarkconnect(chicago, "assault", "burglary")
   
   # plot(alltypes(chicago, linearmarkconnect))