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I have 2 layers, one which is a point layer with entertainment locations and the other is a polygon layer of buildings. I'm tasked to find how many buildings are within a 180m radius of the entertainment locations.

Obviously my first instinct was to create a buffer and then use a spatial join however, if I check the Join_Count column afterwards and compare it to the Select by Location result they don't match which means the Spatial Join counts something extra. After fiddling with the data I came to a conclusion that the Spatial Join is counting other near overlapping buffers.

I'm using ArcGIS 10.7

Edit: the question is how do I get to see the correct number of building inside each buffer (or how do i find out how many buildings i have around each entertainment spot in a 180m radius)

Photo for reference:

https://i.sstatic.net/RBIie.jpg - you can see in this photo that there are 126 selected using the Select by Location option for Object 3

https://i.sstatic.net/YvURb.jpg - and here after the spatial join there are 138 for the buffer from that Object.

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    What's the question?
    – nmtoken
    Commented Apr 9, 2020 at 17:24
  • How do I get to see the correct number of buildings inside each buffer Commented Apr 9, 2020 at 17:47
  • Use spatial join, one to many. Summarise by buffer fid.
    – FelixIP
    Commented Apr 12, 2020 at 5:21
  • I've tried that aswell before but I get the same result of double counting Commented Apr 12, 2020 at 9:31

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You need to use Spatial Join from ArcToolbox, which has the option that you need "HAVE THEIR CENTER IN" located under the Match Option, as you can see below:

enter image description here

You can find the tool from ArcToolbox -> Analysis Tools -> Overlay -> Spatial Join

In this case you will ensure that only polygons where their centroids are located within the buffer will be counted.

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  • I've just tried this but the result comes out as either a 1 or a 0 in the Join_Count column Commented Apr 10, 2020 at 10:14
  • @BaruchSigal It is better to add a screenshot to get a better understanding of your question.
    – ahmadhanb
    Commented Apr 10, 2020 at 10:32
  • I've added 2 photos to the main question, sorry for the misunderstanding Commented Apr 10, 2020 at 14:48
  • Using the centroid option will not count, for example, corners of buildings that are within the 180m radius. Additionally, the centroid option could still pick up other buffers that are closer than 180m. I would consider looping through each point geometry to find the features (I.e. depending upon the size of the feature classes). The Near tool would be ideal if it allowed searching for all features within a search distance rather than only the closest.
    – Aaron
    Commented Apr 10, 2020 at 15:34
  • @Aaron I'm not sure I completely understand what you mean by saying "looping through each point geometry". I've tried the near tool but I get the same result since I have overlapping buffers. Commented Apr 10, 2020 at 16:26

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