[Geocoding] Fresh Nominatim different than nominatim.openstreetmap.org

[Anders Gunnarsson]

Hi

> -----Original Message-----
> From: Sarah Hoffmann [mailto:lonvia at denofr.de]
> Sent: den 10 april 2014 12:17
> To: Anders Gunnarsson
> Cc: geocoding at openstreetmap.org
> Subject: Re: [Geocoding] Fresh Nominatim different than
> nominatim.openstreetmap.org
> 
> Hi,
> 
> On Thu, Apr 10, 2014 at 09:12:32AM +0000, Anders Gunnarsson wrote:
> > We have made a few fresh installations of Nominatim lately according
> > to the documentation on
> > http://wiki.openstreetmap.org/wiki/Nominatim/Installation
> >
> > Our installations sometimes give different results than the official
> on nominatim.openstreetmap.org. So far we have seen the following
> differences:
> >
> >
> > 1). Hits in Norway and Australia get the country code aq (Antarctica)
> 
> That's because people keep annexing Antarctica for their own countries
> in OSM, see e.g. http://www.openstreetmap.org/relation/2978650
> Nominatim is rather sensitive to this issue and responds by annexing
> those countries for Antarctica.
> 
> I had an emergency patch installed on osm.org to prevent that from
> happening but apparently forgot to backport it to the official version.
> I'll try to get around that as soon as possible, feel free to file a bug
> report as a reminder. Unfortunately, you will have to reindex the entire
> country once the patch is installed.

Ok! Any chance I get a patch so I know more or less what I need to do?

> 
> > 2). Differences in importance
> 
> Have you installed the wikipedia data, as of
> http://wiki.openstreetmap.org/wiki/Nominatim/Installation#Wikipedia_rank
> ings
> 

Wiki data has been downloaded and hopefully applied. A lot of places have the exact same numbers, but some places like Zagreb differs a lot.

How can I verify that the import of wiki data was successful?
Is it easy to back trace the calculations for importance, to see what the importance data is based on??

> > 3). Places not found using structured address search
> >
> > Query:
> > http://nominatim.openstreetmap.org/search.php?format=json&city=tao%20y
> > uan%20xian&country=taiwan
> >
> > 10 places found on nominatim.openstreetmap.org vs 0 on our server.
> 
> Check the data of the results on your server on the details page.
> For example for the first result of the query, you should check:
> 
> http://<yourserver>/details.php?osm_type=N&osm_id=60655807
> 
> Is the node a city in Taiwan? Also, check that the search for Taiwan
> works.

It's not, it's a county. Searching for county works in our setup. This search came from an old unit test, which turned out to be somewhat incorrect. I'm still puzzled why the result differs. Also result on osm.org finds the city the test was looking for.

{"place_id":"9174190875","licence":"Data \u00a9 OpenStreetMap contributors, ODbL 1.0. http:\/\/www.openstreetmap.org\/copyright","osm_type":"node","osm_id":"60655807","boundingbox":["24.9937763214111","24.9937782287598","121.301330566406","121.301338195801"],"lat":"24.993777","lon":"121.3013371","display_name":"Taoyuan City, Taoyuan County, 330, Taiwan","class":"place","type":"town","importance":0.62583438050095,"icon":"http:\/\/nominatim.openstreetmap.org\/images\/mapicons\/poi_place_town.p.20.png"}

> 
> Regards
> 
> Sarah

Warm regards,
Anders Gunnarsson