Quality of Administrative Zones

Hi there,

I am still doing research for administrative zones. Extracting those from a OSM dumb is quite a bit buggy right now but I am able to flex it out bit by bit.

Can someone give me a quality feedback? I mean is someone successfully using them or are they at least in some minor areas buggy? How exact are they?

I found some blog posts about those zones but those are two years old or older.

What we want to do is attaching quality measurements like you are leaving this city and entering those villages. You are outside of x,y. The main idea is to find a level of detail to give additional information about a users position without revealing the exact position. Therefore your friends know where you are but can not track you down by a meter.

It depends on the area you’re looking at. I suppose with buggy yea mean you’re left with holes in the map. This is lack of data quality: you can only make a polygon if the relation is a closed line.
The easy way to get valid polygons for a certain area is downloading them from wambacher’ s great service.

Fixing admin areas is strangely satisfying: you can read my post about it here:http://www.openstreetmap.org/user/joost%20schouppe/diary/21540

There is a web beased servive by German user Wambacher that offers all available boundary polygons from admin_level=2 (country) down to level 10 or even 12 IF that data is contained in the main OSM database.

See http://osm.wno-edv-service.de:8080/boundaries/ and try to use the tree navigation panel on the left step by step. You van export one or more boundary lines in different formats like geojson or shapefile etc.

See http://wiki.openstreetmap.org/wiki/User:Wambacher for a table for each country in the world with a first evaluation of hierarchical completenes.

Also try http://openmapsurfer.uni-hd.de/ with a greyscale base layer and “OSM boundaries” as overlay.

Or try http://overpass-turbo.eu … zoo to an area you want to inspect, and try the Wizard there by typing

boundary=administrative and type:relation

. (Try on a small area first, so zoom in a lot first before running the query)