[OSM-talk-ie] Why is Billy parish in Antrim shown as in Athlone Municipal District?

[Alan Grant]

It seems that Nominatim is assigning the island of Ireland as the "parent"
of a lot of parishes and similar boundary relations. Note that it is the
first address item that appears on the details page that Marc linked to.
See the full list in the Parent Of section here:
https://nominatim.openstreetmap.org/details.php?osmtype=R&osmid=7681896&class=place


For all of these, it returns a location near Athlone, presumably because it
is the calculated centre of the island of Ireland.

That sort-of explains why Athlone rather than anywhere else, but it doesn't
explain why the island of Ireland is being treated as the immediate parent
of these parishes in the first place. Especially as it doesn't apply to all
parishes. For example I can't see why the results are different for
Rathbran (which works fine) versus Castlecomer (which doesn't) - see
details at
https://nominatim.openstreetmap.org/details.php?osmtype=R&osmid=6236340&class=boundary
 and
https://nominatim.openstreetmap.org/details.php?osmtype=R&osmid=5351850&class=boundary
respectively.
Unless the "wrong" ones have been added more recently and Nominatim hasn't
fully reflected them in its database? I did notice that Rathbran has a
"computed postcode" and Castlecomer doesn't, but I have no idea if that is
relevant.

As Marc said, this may be something only Nominatim maintainers can answer.

Regards
Alan

On Tue, 28 Apr 2020 at 15:18, Marc Gemis <marc.gemis at gmail.com> wrote:

>  it should be returned when the object is outside. => it should NOT be
> returned when the object is outside
>
> On Tue, Apr 28, 2020 at 3:16 PM Marc Gemis <marc.gemis at gmail.com> wrote:
> >
> > Brian,
> >
> > I looked at
> https://nominatim.openstreetmap.org/details.php?osmtype=R&osmid=10993573&class=boundary
> > Normally this allows me to understand why a certain admin hierarchy is
> > returned. In this case, I do not understand why the distance is 0.1746
> > for the Athlone Municipal District.
> > It seems to be the admin level 8 that is closest to the centre of
> > Billy Parish. But as it is a relation, it should be returned when the
> > object is outside. (perhaps the relation was not properly closed at
> > the time Nominatim imported the data?)
> >
> > If none here replies you should reach out to the Nominatim maintainers.
> >
> > regards
> > m
> >
> > On Tue, Apr 28, 2020 at 12:40 PM Brian Hollinshead
> > <brian at hollinshead.net> wrote:
> > >
> > > During the stay at home I have added many CofI parishes to OSM based on
> > > single or combinations of civil parishes.
> > > Please see Billy Parish 10993573, it suggests it is in County
> Roscommon!!
> > > This applies to a number of others as well. Please can somebody
> explain why
> > > to me and also how or who can rectify it. While they all display OK it
> > > might be disconcerting to a person doing a search.
> > > Thank you.
> > > _______________________________________________
> > > Talk-ie mailing list
> > > Talk-ie at openstreetmap.org
> > > https://lists.openstreetmap.org/listinfo/talk-ie
>
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