[OHM] change and persistence in urban environment

[Tim Waters]

Thought I would share this blog post by a fellow historical OSM mapper
which you may find interesting.

In it, he compares 3 cities (Notingham, UK, Zurich, CH, and
Pittsburgh, US) and derives a form of classification based on how many
changes have occurred in the areas.

http://sk53-osm.blogspot.co.uk/2013/02/persistence-in-urban-environment-1.html

Regards,

Tim