minglingF: Spatial Mingling Index

Description

Compute the Mingling index for a given multitype point pattern.

Usage

minglingF(X, r=NULL, target=NULL, ratio=FALSE, ...)
mingling.index(X, r=4, ntype="knn", ...)

Arguments

Multitype point pattern of class ppp (see package 'spatstat')

Vector of sizes for neighbourhoods, e.g. geometric graph with different ranges.

target

Default NULL. Calculate only for target type. If NULL computes for each type + mean over all types.

ratio

Default FALSE. If TRUE, scale the typewise values $M_t$ using formula $(1-M_tau)/lambda_tau$ which equals 1 for Poisson CSR.

ntype

The original mingling index uses knn neighbourhood type.

...

Further parameters for the function segregationFun.

Value

Returns an fv-object, see spatstat for more information.

Details

Extension of Mingling index introduced by Lewandowski\&Pommerening 1997. Measures the proportion of alien points in the neighbourhood of a specific type typical point of the pattern.

If no specific type is given, the function takes mean over all types. A typewise value is more useful, so they are also included.

The function minglingF is the main calculation function. Uses function segregationFun.

The function mingling.index is a shortcut to get a single value for the pattern. Uses 4-nn graph by default, which is the original Mingling index used by Lewandowski\&Pommerening 1997 and Graz 2004.

References

Graz: The behaviour of the species mingling index $m_{sp}$ in relation to species dominance and dispersion. Eur. J. forest research. 123:87-92, 2004.

Lewandowski, Pommerening: Zur Beschreibung der Waldstruktur - Erwartete und beobachtete Arten-Durchmischung. Forstwiss Centralbl, 116:129-139, 1997.

Rajala, Illian: A family of spatial biodiversity measures based on graphs, Env. Ecol. Stat. 2012