OSM has pretty poor neighborhood coverage in the
US. We have around 1100 place=neighbo[u]rhood.
Geonames has ten times that at 11,000 (feature
class P.PPLX - not sure if all of those are
neighborhoods) and Zillow has 7,000. Both these
data sets are provided under (different) CC
licenses. Could we use either Geonames or Zillow
to drive improvement to neighborhood name
coverage in OSM? I am not proposing an import,
but a local MapRoulette challenge might work
where people with local knowledge accept /
reject proposed neighborhood points, or
something along those lines.
Martijn
I don't use points (a POI with place=* or
neighbourhood=* tag) but rather named polygons
which surround/define a given named residential
area. These seem to work just as well:
What I've done in my city is to get the (public
domain) digital city data for how parcels are
grouped together into polygons defining
residential neighborhoods, with names in the
name=* tag (and even numbers for each residential
neighborhood, which I've put into the ref=* tag).
These get an additional landuse=residential tag,
and voilá, OSM (the database), mapnik and
Nominatim all capture/display/index each
neighborhood properly (Nominatim nicely and
correctly as "Residential area.")
The same data sets also contain outer-parcel-edge
boundaries for commercial and industrial
districts, which of course get landuse=commercial
and landuse=industrial tags (respectively), as
well as THEIR name=* (and ref=*) tags. As a
result, our city displays very nicely, all
neighborhoods/districts show up in Nominatim, and
the OSM database contains definitive, correct
polygons, straight from a public domain source
(the city GIS department).
There are a very small number (two, three?) of
"additional" data points which my neighbors use
as community names (like "East Park" or
"Midtown") which the city doesn't actually
define, but people who live and/or work there do.
For these, I use place=locality, name=* tags, and
they render with a slightly different font (and
smaller type size) than the
neighborhoods/districts above. For these, I
place the point at a significant "cultural
centroid" for those small sub-communities
(place=suburb is too big, though I have also
defined four of those in my city of 60,000 --
suburb points also display with
distinct/different typeface/size, and at
"certain" zoom levels which make it clear they
are suburbs). From both an "in the OSM DB" and a
"how does mapnik display this" (in addition to
how Nominatim indexes), I believe this is
completely correct, and they look nice, too. I
sincerely believe anybody who lives in these
neighborhoods would agree.
I would guess many medium- and larger-sized
cities have these sorts of datasets available:
they are just big polygons that surround a
neighborhood or commercial/industrial district:
no "single point" required. While these might
take up more space in OSM's database, the extra
points for the polygon-defining way makes them
quite exact, and mapnik's rendering is in the
very center of each polygon: a nice way to do it.
I invite you to take a look (within the City limits):
http://www.openstreetmap.org/?lat=37&lon=-122&zoom=14&layers=M
I don't think Zillow or Geonames should be leaned
on too heavily (if at all) to define these:
where neighborhoods begin and end is very much a
local thing, and usually the City itself (or the
County for unincorporated areas) or people who
live locally are best at defining these. That's
why I'd say MapRoulette is a poor candidate for
doing this: you won't get local knowledge,
you're just crowd-sourcing what effectively
becomes an import among many, and they don't
really know whether the data are high quality or
not.
SteveA
California
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