Before, During, After

Given the three points of interest for a user, a triangle is drawn. Comparing these triangles is done by the following:

Various metrics may then be computed:

isoceles_ratio = The ratio of before-during to during-after edges.

Users can then be filtered by the following triangle paramaters:

1. Perimeter
2. Length of Before-After Edge (if they returned to the same place from where they left or not)

Putting these variables together, we can search for users who’s shelter locations make triangles of under a threshold perimeter with a before-after edge under a threshold and an isoceles ratio within a threshold

How to determine these thresholds? See the latest posts