Calculating point density within a buffer

BeckyGajewski — Thu, 06 Sep 2012 21:09:10 GMT

Hello all,

I'm relatively new to density analysis in ArcGIS, so this may be a simple question, but here it goes.

I'm trying to calculate the density of businesses within a 1-mile buffer of my study participants. I have point layers for both the businesses and participants. I used the Point Density tool to calculate the density of businesses with the following settings:

Output cell size: 100m
Neighborhood: Circle
Radius: 1609 map units (my map units are in meters)
Area units: Square miles

Now that I have a density raster, how do I go about determining the densities within a mile of my participants? Am I correct in my interpretation that the value of the cells that coincide with my participant points are the values I'm looking for?

Thanks very much for any direction you can provide!

Re: Calculating point density within a buffer

Anonymous User — Tue, 11 Sep 2012 17:14:18 GMT

One thing you can do is to create a field in the point shapefile called count and use the field calculator to give every point a value of 1. Next you need to convert your to points to rasters using the point to raster tool and have the count field as the value. You can use the same cell size of 100 m and use SUM for the assignment type (this will ensure that if there are 2 points within 100 m the cell value will be 2 ect.). Finally you can run focal statistics with a circle of 5280 ft (or 1609.344 m if the units are in meters) using the sum statistic. This will tell you how many points are within one mile.

Caleb

topic Calculating point density within a buffer in ArcGIS Spatial Analyst Questions

Calculating point density within a buffer

Re: Calculating point density within a buffer