spatstat.core: GmultiInhom – R documentation

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GmultiInhom

Inhomogeneous Marked G-Function

Description

For a marked point pattern, estimate the inhomogeneous version of the multitype G function, effectively the cumulative distribution function of the distance from a point in subset I to the nearest point in subset J, adjusted for spatially varying intensity.

Usage

GmultiInhom(X, I, J,
             lambda = NULL, lambdaI = NULL, lambdaJ = NULL,
             lambdamin = NULL, ...,
             r = NULL,
             ReferenceMeasureMarkSetI = NULL,
             ratio = FALSE)

Arguments

`X`	A spatial point pattern (object of class `"ppp"`.
`I`	A subset index specifying the subset of points from which distances are measured. Any kind of subset index acceptable to `[.ppp`.
`J`	A subset index specifying the subset of points to which distances are measured. Any kind of subset index acceptable to `[.ppp`.
`lambda`	Intensity estimates for each point of `X`. A numeric vector of length equal to `npoints(X)`. Incompatible with `lambdaI,lambdaJ`.
`lambdaI`	Intensity estimates for each point of `X[I]`. A numeric vector of length equal to `npoints(X[I])`. Incompatible with `lambda`.
`lambdaJ`	Intensity estimates for each point of `X[J]`. A numeric vector of length equal to `npoints(X[J])`. Incompatible with `lambda`.
`lambdamin`	A lower bound for the intensity, or at least a lower bound for the values in `lambdaJ` or `lambda[J]`.
`...`	Ignored.
`r`	Vector of distance values at which the inhomogeneous G function should be estimated. There is a sensible default.
`ReferenceMeasureMarkSetI`	Optional. The total measure of the mark set. A positive number.
`ratio`	Logical value indicating whether to save ratio information.

Details

See Cronie and Van Lieshout (2015).

Value

Object of class "fv" containing the estimate of the inhomogeneous multitype G function.

Author(s)

Ottmar Cronie and Marie-Colette van Lieshout. Rewritten for spatstat by Adrian Baddeley Adrian.Baddeley@curtin.edu.au.

References

Cronie, O. and Van Lieshout, M.N.M. (2015) Summary statistics for inhomogeneous marked point processes. Annals of the Institute of Statistical Mathematics DOI: 10.1007/s10463-015-0515-z

Examples

X <- rescale(amacrine)
  I <- (marks(X) == "on")
  J <- (marks(X) == "off")
  mod <- ppm(X ~ marks * x)
  lam <- fitted(mod, dataonly=TRUE)
  lmin <- min(predict(mod)[["off"]]) * 0.9
  plot(GmultiInhom(X, I, J, lambda=lam, lambdamin=lmin))
  # equivalent
  plot(GmultiInhom(X, I, J, lambdaI=lam[I], lambdaJ=lam[J], lambdamin=lmin),
       main="")

spatstat.core

Core Functionality of the 'spatstat' Family

v2.1-2

GPL (>= 2)

Authors

Adrian Baddeley [aut, cre], Rolf Turner [aut], Ege Rubak [aut], Kasper Klitgaard Berthelsen [ctb], Achmad Choiruddin [ctb], Jean-Francois Coeurjolly [ctb], Ottmar Cronie [ctb], Tilman Davies [ctb], Julian Gilbey [ctb], Yongtao Guan [ctb], Ute Hahn [ctb], Kassel Hingee [ctb], Abdollah Jalilian [ctb], Marie-Colette van Lieshout [ctb], Greg McSwiggan [ctb], Tuomas Rajala [ctb], Suman Rakshit [ctb], Dominic Schuhmacher [ctb], Rasmus Plenge Waagepetersen [ctb], Hangsheng Wang [ctb]

Initial release

2021-04-17