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<p class="MsoNormal">For those who have worked on analyses in ArcGIS, nothing is more familiar with to run the Identity overlay analysis. I have a layer of 85 points (clinics), and for each point I created three buffers of 30, 50, and 80 miles. The three layers
of buffers were then union-overlaid together to create a combined layer. I then ran an identity overlay of the 85 points (clinics) layer with the union combined layer to assign the buffer attributes to the clinics (points). The purpose of doing it this way
is to have just one run will be able to find out who is the neighbor(s) within 30 miles, within 50 miles, and within 80 miles. This approach is very efficient for large datasets. <o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Surprisingly, when I did the identity overlay of the 85 points (clinics) layer with the union layer, the output give me 2,400+ points with many redundant points. I called ESRI tech support and it just can’t explain it.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Does anyone have similar experiences to share or shed some light on this puzzle?<o:p></o:p></p>
<p class="MsoNormal">Thanks<o:p></o:p></p>
<p class="MsoNormal">Yurong Tan<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Office of Healthcare Inspections<o:p></o:p></p>
<p class="MsoNormal">Office of Inspector General<o:p></o:p></p>
<p class="MsoNormal">U.S. Depart of Veterans Affairs<o:p></o:p></p>
<p class="MsoNormal">352-337-2375<o:p></o:p></p>
<p class="MsoNormal"> <o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
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