[OSM-talk] The completeness of OpenStreetMap

[Edward Johnson]

I'm compiling some research into ways in which we can think of a map as complete and how complete OSM is. I was just wondering if anyone had any thoughts on the topic. My initial ideas have been posted on my blog http://edwardmjohnson.wordpress.com/ and I will continue to update this until I'm satisfied I know everything there is to know about the completeness of the map!

One of the most interesting parts is how can we quote completeness of the map? My first thought was a stage system as quoted below

* Preliminary stage - GPS tracks gathered or area has yahoo imagery.

* Stage 1 - Nodes and ways mapped onto OSM using GPS track or aerial imagery.
    
* Stage 2 - All roads named and roughly categorised

* Stage 3 - Map good enough for satellite navigation. All one-way streets, and restrictions tagged along with accurate street categorisation.

* Stage 4 - All POIs (i.e. post boxes, bus stops, pubs, restaurants, supermarkets etc.) tagged.

These stages may or may not occur in sequential order and each stage can be quoted complete in terms of percentages. For example we might say that London is 100% complete for Preliminary and stages 1 and 2, but only 60% stage 3 complete and 20% stage 4 complete. The hard question is how do we accurately measure these percentages.

What are other people's ideas?