Nick Eubank writes:
> Using `kest` to estimate a ripley's K for a country. This is a question about the 'spatstat' package. The function name is 'Kest'. > The authors of the package suggest isotropic is best when computationally > tractable for > irregular shapes, but I noticed in Ripley (1988) that this correction is > only "unbiased provided E is convex", where E is the boundaries of study. This is covered at length in Chapter 7 of the 'spatstat book' <https://www.crcpress.com/Spatial-Point-Patterns-Methodology-and-Applications-with-R/Baddeley-Rubak-Turner/p/book/9781482210200 The isotropic corrected estimate is unbiased for all r < R, where R is the radius of the smallest circle that encloses the entire window (assuming the window is connected). > With that said, the picture in Ripley (1988) illustrating this correction > is NOT convex (it's a kidney shape). So the statement above applies to this window. > I know this isn't quite an "r-implementation" question, but: anyone know if > isotropic correction is unbiased for an odd shape like a country-outline > (in this case Sweden)? Or should i use the `border` correction? Use the isotropic correction. Adrian Baddeley [[alternative HTML version deleted]] _______________________________________________ R-sig-Geo mailing list R-sig-Geo@r-project.org https://stat.ethz.ch/mailman/listinfo/r-sig-geo
