[Talk-us] proposed first principles for United States road tagging

[Kevin Samples]

Hi,
I am a proponent of using the Highway Functional Classification System, 
which Alan has described below and is on the wiki....
http://wiki.openstreetmap.org/wiki/Highway_Functional_Classification_System

I've classified roads in Clarke County, Georgia and the surrounding 
counties using the HFC System with what I think are good results.
http://osm.org/go/ZSCaTrq

Kevin

On 3/4/2010 6:12 PM, Alan Mintz wrote:
> At 2010-03-04 09:38, McGuire, Matthew wrote:
>    
>> ...
>> 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.
>>      
> I disagree. Even if this is what was intended, it's certainly less useful
> than the others. When I zoom out a certain amount, what I want to see is
> the local (aka residential in OSM) roads disappear. Further out still, I
> want to see the tertiary roads disappear, etc. This is what's useful when
> trying to map a route through an unknown area - you want to stick to the
> main roads that get you there with better road conditions, fewer
> intersections, etc.
>
> As an example, in this area:
> http://www.openstreetmap.org/?lat=34.426&lon=-117.664&zoom=11&layers=B000FTF
> , 2-land paved roads are few and far between, making them important
> tertiary or secondary connections. A road with the same characteristics in
> the city would be unclassified, as there are much better roads. It's all
> relative to the area, which is why I don't think it's reasonable to
> classify by any objective characteristics - you have to know or survey the
> area in order to know how to classify them. Perhaps some people with a lot
> of experience may be able to do this from satellite imagery.
>
> I believe this closely matches what I see in transportation sections of a
> city's general plan. I think it's useful to use these as guidelines when
> classifying roads. Many cities/counties of any reasonable size make these
> available on their website. They usually have:
>
> - freeway, expressway, etc. = OSM motorway or trunk
> - primary arterial = OSM primary
> - secondary arterial = OSM secondary
> - minor arterial and/or collector = OSM tertiary
> - local = OSM residential or unclassified
>
> --
> Alan Mintz<Alan_Mintz+OSM at Earthlink.net>
>
>
> _______________________________________________
> Talk-us mailing list
> Talk-us at openstreetmap.org
> http://lists.openstreetmap.org/listinfo/talk-us
>
>
>