I'm trying to understand how ArcGIS 10.1 handles kernel density values and how these values are reported in the legend. For example, the following parameters were used for the KDEs in the attached figure:

Projection Info

  • Projection: UTM 17N
  • Linear Unit: M

KDE Tool Parameters

  • Output cell size: 0.01

  • Search Radius: 1m (left image) and 2m (right image)

  • Area Units: SQUARE_MAP_UNITS

I know cell size has no affect on the legend values. Yet how does the search radius affect the legend values? For example, if the search radius = 1m, then the area = pi. And if the search radius = 2, then the area = 4pi. Does ArcGIS automatically scale this to the projection map units (e.g. 1 m^2)? Specifically, what are the units displayed here?

enter image description here

  • You have it backwards, all that matters is the cell size for the raster in interpreting the density. Unfortunately, many different programs report the density estimates in different units (confusing - a related prob. in stats are histograms reporting different units). Does the sum of your raster equal the number of original units used for the density estimation?
    – Andy W
    Jun 4, 2013 at 1:16