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Nominatim - Why is a small nearby village included in a location description?

1

Looking at http://nominatim.openstreetmap.org/details.php?place_id=35602344, http://nominatim.openstreetmap.org/details.php?place_id=39331659 and a good number of the roads around the area, they all seem to incorrectly include 'Wick' using the place node of a small nearby village - https://www.openstreetmap.org/node/30133595

I haven't been able to work out why Nominatim includes the 'Wick' place node in this case, can anyone help explain it for me? Thanks.

asked 05 Jun '14, 15:54

Elliveny's gravatar image

Elliveny
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accept rate: 0%

edited 05 Jun '14, 16:00


One Answer:

2

That's because Wick is just a node and therefore hasn't an exact boundary. As a consequence, Nominatim has to guess it's boundary and obviously it can't be 100% right about it.

But I wonder whether Whick is really a village and not just a suburb?

answered 05 Jun '14, 18:02

scai's gravatar image

scai ♦
33.3k21309459
accept rate: 23%

1

Suburb or city doesn't really matter for Nominatim. I had to draw a administrative boundary around a neigborhood node in order to prevent Nominatim to add it to each street in the village.

(06 Jun '14, 12:49) escada
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Sure, Nominatim can't know whether the streets are located inside the neighborhood if there is no exact boundary either. But in this case the mentioned places are already part of another suburb. So if Wick really is a suburb and gets tagged as a suburb, then Nominatim would no longer assign these places to Whick. Of course this is only half the solution, because the suburbs don't have an exact boundary either.

(06 Jun '14, 13:05) scai ♦
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@escada - Can you provide an example? I'm keen to dig into this a bit more and could do with something to compare to please.

(10 Jun '14, 14:11) Elliveny

I've added the relation Bosstraat https://www.openstreetmap.org/relation/3777416 Unfortunately, I now notice that it does not work. e.g. Oude Reetse Baan 89, Boom is still linked to this neighborhood. It is certainly not part of it. I though I edited some address at that time and I got rid of the pesky "Bosstraat"

(10 Jun '14, 14:27) escada

Oude Reetse Baan 89, Boom is linked to the neighborhood node and not the relation you created, according to Nominatim's detail page (funny place ID, btw.). I'm not quite sure how to prevent that and it seems appropriate to ask a new question about this issue.

(10 Jun '14, 15:25) scai ♦

I don't know if it would work at all. But I do know that if it works, then you need to use matching importance for the admin level and the place node. Relation Bosstraat is at admin level 10 (calculated importance=20). The node for Bosstraat is tagged as neighbourhood (calculated importance=22).

See: Nominatim Development Overview

(10 Jun '14, 15:35) cartinus

Yesterday I removed the place node and now it seems that everything is OK. The neighborhood is only added to those streets that are actually in the neighborhood, due to the administrative boundary. I'll now try to add the admin centre again and see what happens.

(12 Jun '14, 06:03) escada
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