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rkernel-densityspatstat

How is adaptative.density() (spatstat) managing duplicated points and default f value


I can not find this information in the reference literature [1]

1)how adaptative.density() (package spatstat) manage duplicated spatial points. I have duplicated points exactly in the same position because I am combining measurements from different years, and I am expecting that the density curve is higher in those areas but I am not sure about it.

2) is the default value of f in adaptative.density() f=0 or f=1? My guess is that it is f=0, so it is doing an adaptive estimate by calculating the intensity estimate at every location equal to the average intensity (number of points divided by window area)

Thank you for your time and input!


Solution

  • The default value of f is 0.1 as you can see from the "Usage" section in the help file.

    The function subsamples the point pattern with this selection probability and uses the resulting pattern to generate a Dirichlet tessellation (if there are duplicated points here they are ignored). The other fraction of points (1-f) is used to estimate the intensity by the number of points in each tile of the tessellation divided by the corresponding area (here duplicated points count equally to the total count in the tile).