On 12/04/11 07:32, Barry Rowlingson wrote:
On Mon, Apr 11, 2011 at 4:49 PM, smoluka<smol...@geo.oregonstate.edu> wrote:
Can anyone tell me why I would get different average nearest neighbor values
for the same set of coordinates between ArcGIS 10 and R? Sometimes the
difference in distance is over 1.3 km.
Edge correction? In a spatial point pattern, points near the boundary
of your window are less likely to have a near neighbour because only
some of the surrounding space can possibly have points. I think
functions in spatstat will correct for this.
No. Not as far as I am aware or can discern. The function
nndist() does ***not*** invoke any edge correction. It simply
calculates the distances as they are, for the points that appear
in the window, and takes the appropriate minima.
cheers,
Rolf Turner
Make a simple test example and tell us what functions you are using.
And also try the r-sig-geo mailing list for this sort of thing.
Barry
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