Find Meeting Locations tool - why are the meeting polygons shaped like that?

Question

The Esri Defense and Intell Showcase gave an outstanding demo of the Find Meeting Locations tool used with other Pattern of Life tools.

I'd like to understand the analytics and presentation.  Like, why does the meeting locations output polygon layer look like this?

The Pro 2.7 tool reference  only says:

The tool creates two output feature classes: an area feature class indicating the locations identified as potential meeting sites and a point dataset as the centroid of the unique meeting location.

Not much to go on.  There is slightly more info in this clip which I extracted from the Showcase video and posted on YouTube.  At 2:57 in the video, the analyst says:

"The blue polygon is going to be the median location, so this is going to be an inclusive area
of where a lot of meetings are occurring as determined by the tool."

What does this mean?  Why was this analytic chosen?

I see almost no ArcGIS references median location .

Would it make more visual and logical sense to use one of the density tools that produces a typical ellipse for analysis like this?  Otherwise, what is the meaning of pointy end shapes like this?  How are we supposed to make use of it?

Thanks.

DonBarker · Answer

Thanks for this clarification.  "Convex hulls from the extent of the points" makes more sense than the "median location" we read in the documentation for this tool.

JamesJones4 · Answer

Hi Don - We are created convex hulls from the maximum extent of the points that meet the criteria for meeting.  Some of the pointy parts that you have seen/identified are due to a few factors.  In the specific example above, there is a road that is acting as a natural chokepoint for the tracks where there are filtering down into a general "point". Since we are creating the convex hull from this maximal extent, on occasion abnormal shaped features like this will get created.  In the case of when we have multiple meeting areas overlapping on top of each other, we are dissolving those meeting areas to account for the total area in which meeting have occurred.

I will update the documentation for this tool to better reflect this.  Thanks for the question!

DanPatterson · Answer

the sample wasn't as clustered as you thought... one outlier is all it takes