topic Re: Create buffer based on occurrence frequency? in Data Management Questions

Create buffer based on occurrence frequency?

KatieGerloff — Fri, 09 Feb 2018 06:26:55 GMT

I am using ArcMAP 10.4.1.

I have several point shapefiles containing different occurrence data for two different species of flower (from multiple sources, hence the multiple shapefiles). I want to create a buffer from a central point that includes a quantity of at least 50 each of each species. I'm familiar with the general buffer tool, so for example, I can create a buffer of a certain size and clip to it, but what I'm hoping to do is create a buffer that contains at least 50 occurrences of each species regardless of the size, from a certain point (i.e. a city).

I'm hoping this can actually be done in ArcMAP? I've been searching this forum, StackExchange and elsewhere, and can't find this anywhere.

Re: Create buffer based on occurrence frequency?

DanPatterson_Retired — Fri, 09 Feb 2018 10:57:19 GMT

That summary needs to be created and joined as a field to the point's table so you can buffer by a data in a field

http://pro.arcgis.com/en/pro-app/tool-reference/analysis/summary-statistics.htm

http://pro.arcgis.com/en/pro-app/tool-reference/analysis/buffer.htm

Re: Create buffer based on occurrence frequency?

AbdullahAnter — Fri, 09 Feb 2018 21:11:15 GMT

Try to use X and Y fields as Analysis fields in Grouping Analysis tool .

And Change Number of groups in the tool each time to to get best result .

Re: Create buffer based on occurrence frequency?

ChrisDonohue__GISP — Fri, 09 Feb 2018 21:52:11 GMT

Just an idea - a different approach based on the theory that you want the 50 closest to the fixed central point in the City. If that is the case:

Combine all your data of each species into a feature class for each species (so you end up with two feature classes).
Create a point feature class of your central city point.
Then for each species layer, run one of the following tools to determine the distance from your central point to each of the features in a species layer (read over each to determine which way you want to do this):
Pointdistance (for older versions of ArcGIS) Point Distance—Help | ArcGIS for Desktop
Near Near—Help | ArcGIS for Desktop
Generate Near Table Generate Near Table—Help | ArcGIS for Desktop
Then sort each layer by Distance to come up with the top 50. Find the distance to the 50th feature for each species and that will become a distance value to then buffer based on your central point.

Chris Donohue, GISP