I have 50m X 200m polygon which has several small polygons inside. I would like to define how scattered small polygons inside a big polygon. I was wondering if there is a tool which can calculate some index based on the distribution of polygons across a big polygon. For example, if polygons are gathered it would give index 0 and if they are scattered well index would be 1. Is there any tool that I can use? ArcGIS or QGIS would be good.