[Imports] Import of Placename Database of Ireland

Greg Troxel gdt at ir.bbn.com
Thu Jun 4 13:53:05 UTC 2015

Rory McCann <rory at technomancy.org> writes:

> Hi Greg,
> On 04/06/15 14:15, Greg Troxel wrote:
>> Generally there are objections to adding the ref tag.  Basically the
>> notion is that you have to deal with the hard part of conflation when
>> you don't have it, so you might as well skip it.
> I'd like to add the "logainm:ref" tag, not the "ref" tag. It would a
> string of numbers, and is "The reference of this object according to the
> Logainm database". (I'm open to suggestions for a better tag. "logainm:id"?)

That is exactly what people generally object to.

> The OSM objects I want to add tags to are administrative polygons in
> OSM, and legally defined administrative areas (some historical and not
> in use anymore), not fuzzy place names. The Logainm database has one
> point for each object (rather than full polygons), we'll use that to aid
> finding the corresponding OSM object (along with the name and
> hierarchy), but we can't/won't import the Logainm geometry.

So it has names that belong on polygons, but represents them as points
:-)    That seems like it will make things harder.

OSM has a notion of places vs boundaries, but I think the reality of the
db is a bit confused on this.   Also, we talk about populations of
places, and in crowded parts, it doesn't make sense to talk about
populations of place names vs named entities with boundaries.   But
that's not relevant to your project if you're only talking about legal
entities with boundaries.

>> In general, I had a hard time reading the wiki page and understanding
>> precisely what it is you actually want to do.  I certainly get the
>> larger point and don't have an issue with it - it's that I don't know if
>> the source is nodes or polygons, how the place name/legal entity name
>> issue works, and whether you will be conflating nodes with polygons, or
>> polygons with polygons, etc.
> As well as official_name:*'s, we can add "name:ga", Irish names. The
> current townland/barony/ED/civil parish mapping project only really has
> access to the English names of these boundaries. Ireland is legally
> bilingual (Irish & English). The Placenames Database of Ireland is a
> government agency that decides the official (Irish) place names of
> things (as well as partially a historical research goal). By importing
> this data we would have Irish names for many Irish administrative
> boundaries.

Sorry, I got that.  What I meant more was along the lines of:

for each place in the database

  given the names and the point coordinates, search for an osm polygon with
  tags boundary=administrative with admin_level=8  [and fill in about if
  you are matching on coordinates, or matching on name, or ?]    This
  will require being clear if all the placenames are at the level=8 (or
  the same level - I'm unclear if your provinces/counties are 3/4 or 4/6
  - not trying to raise that).

and then explain what happens when there are fuzzy matches vs exact, and
how this won't result in overwriting or duplicating of hand-mapped data
without someone really thinking about it, etc.

Again, I'm not objecting to your process or goals - it's just that this
sort of conflation is very tricky business.
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