The Cohesion Index is the average Euclidean distance between all pairs of interior points in the polygon. To improve performance, the calculation is calculated for 30 samples of 1000 randomly selected points in the polygon's interior. The Cohesion Index is the average of these samples. The Cohesion Index is normalized using the Equal Area Circle (EAC) as follows:

The Cohesion Index gives all points in the shape an equal weight. It is appropriate to use when...

- the average distance between points is needed
- the distribution of the shape about the center is not relevant
- a measure of compactness is needed

Cohesion Index results for select shapes...