So, aside from interstates (which it seems like everyone agrees should be tagged as motorways?), should/could "System" be abstracted out of road tagging definitions?
On Thu, Mar 4, 2010 at 11:54 AM, Apollinaris Schoell <[email protected]> wrote: > > On 4 Mar 2010, at 9:38 , McGuire, Matthew wrote: > >> I see three dimensions of road classification at play here. >> >> 1) System >> 2) Function >> 3) Observed Character >> >> System is the easy one. That is the road system(s) that that the road >> belongs to especially for signage, but also for road funding channels, and >> maintenance responsibility. And I agree that in practice, Census Feature >> Class Codes have been used (incorrectly) to identify the system to which a >> road belongs. >> > > exactly, we should start tagging this with an operator tag or something > similar. many osm mappers don't care but road enthusiasts do. > >> Function describes the role a road plays in a road system and the types of >> trips (volume and length) it supports based on travel demand and trip >> generation. This is what the Highway Functional Classification System is >> designed for. It is used by Metropolitan Planning Organizations to >> distribute transportation funding. >> >> A road's Observed Character is what kind of road it appears to be to a >> person on the road. For general purpose maps, using observed character to >> classify the roads intends to match a person expectations to what they see >> on the ground. Character is highly correlated with function, but is not the >> same. >> >> I think Observed Character is what OSM is trying to achieve with the highway >> tag. I think this because the OSM tag descriptions for highways have photos >> and describe how the road looks, and you cannot determine system or function >> from a photograph. I also think it is what the Census Feature Class Code >> definitions describe. >> > > 2,3 define what a navi or routing engine should use for best/fastest route > and there is a wide agreement in many countries that this is how the highway > tag should be used. no hard rule defined by either one. also local and > relative importance of a road plays a role. In a city a 2-3 lane road might > be tertiary but out in the country a primary road may have one lane in each > direction. > > good old discussion on this topic > http://www.mail-archive.com/[email protected]/msg00594.html > > >> I would like to see all three dimensions. >> >> Matt >> >> >> >> -----Original Message----- >> From: David ``Smith'' [mailto:[email protected]] >> Sent: Thursday, March 04, 2010 9:33 AM >> To: McGuire, Matthew >> Cc: Nathan Edgars II; [email protected] >> Subject: Re: [Talk-us] proposed first principles for United States road >> tagging >> >> On Wed, Mar 3, 2010 at 10:45 AM, McGuire, Matthew >> <[email protected]> wrote: >>> The US Census Feature Class Code has descriptions of most types types of >>> roads. >>> This would at least tie it to an existing US standard. >>> >>> http://www.census.gov/geo/www/tiger/appendxe.asc >>> >>> This designation exists in many OSM roads tagged with TIGER:CFCC. However >>> most roads could definitely use some refinement. We could strip the TIGER >>> from the tag to just cfcc then refine it from there. >> >> The original TIGER import did in fact use CFCCs to determine highway >> class. It produced values of motorway, motorway_link, primary, >> secondary, and residential. We've been refining that for 3 years now. >> The problem is, this comes from the Census Bureau. They really don't >> care about a road's functional importance. There are CFCCs for many >> other things besides roads. And the few CFCCs assigned for road >> features are essentially based on whether the road is an Interstate, a >> US route, or a State Route, which doesn't correlate well with a road's >> functional classification. >> >> What's more useful is the Highway Functional Classification System. >> The name sounds like what we want to do. And it's from the Federal >> Highway Administration, so they actually care about roads. I've also >> put forward guidelines for translating HFCS to OSM. >> <http://wiki.openstreetmap.org/wiki/Talk:United_States_roads_tagging#Discussion> >> (Sort of buried in a wall of text. I should probably repost those >> guidelines in my userspace.) >> >> -- >> David "Smith" >> a.k.a. Vid the Kid >> a.k.a. Bír'd'in >> >> Does this font make me look fat? >> _______________________________________________ >> Talk-us mailing list >> [email protected] >> http://lists.openstreetmap.org/listinfo/talk-us > > > _______________________________________________ > Talk-us mailing list > [email protected] > http://lists.openstreetmap.org/listinfo/talk-us > _______________________________________________ Talk-us mailing list [email protected] http://lists.openstreetmap.org/listinfo/talk-us
