Re: [Talk-us] CDPs and admin_level
On 10/12/09 10:28 AM, Bill Ricker wrote: I sympathize with Greg, and if the surveyors and computational mappers ruled the world, the real world we seek to model will be simpler. On Mon, Oct 12, 2009 at 12:44 PM, David Lynchdjly...@gmail.com wrote: where city limits cross county lines, WTF? Where does that happen? down where a county is called a parish and is region within sound of a steeple? NYC inverts normal, iirc NYC is effectively a federation of city-counties called boroughs, but no county line crosses NYC boundary, right? When Boston adsorbed towns in adjacent counties, Suffolk county gained land too -- and likewise Boston and Suffolk released towns in the harbor to a non-adjacent (on land) coastal county. (as a result, Norfolk Co Mass is reputedly the only tripartite noncontiguous county separated by towns in other counties not by water ) If State and National electoral districts are included, the gerrymander boundary will assuredly cross, not follow, admin boundaries higher than Ward Precinct, which may be redrawn to convenience the gerrymander. The Wikipedia list below links both to cities that exist separately in different counties (as in New York) and to cities that exist as one unit in multiple counties (as in Ohio): http://en.wikipedia.org/wiki/List_of_U.S._cities_in_multiple_counties Coincidentally, Louisiana doesn't have any cities listed there. I once lived in a Louisiana parish, but not really within sound of a steeple. There's an exception to every rule. :) -- Minh Nguyen m...@zoomtown.com [[en:User:Mxn]] [[vi:User:Mxn]] [[m:User:Mxn]] AIM: trycom2000; Jabber: m...@1ec5.org; Blog: http://notes.1ec5.org/ ___ Talk-us mailing list Talk-us@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk-us
Re: [Talk-us] CDPs and admin_level
On Tue, Oct 13, 2009 at 5:31 AM, David ``Smith'' vidthe...@gmail.com wrote: On Mon, Oct 12, 2009 at 8:14 PM, Anthony o...@inbox.org wrote: You're still acting like the tags are put on regions, when the tags are actually put on borders. It's both. The relation (specifically, boundary and multipolygon relations) is meant to describe not just some borders of a region, but all of its borders, in a way to make it clear whether a given point is in that region or not. Therefore, the relation defines a region. You put tags on the relation, so you are effectively tagging the region, not just its borders. I was talking specifically about the admin_level tag though, since that's the one you were saying shouldn't cross. Obviously the boundary relation should be defined to reflect reality - if a city region intersects multiple county regions, then that's the way it has to be tagged. ___ Talk-us mailing list Talk-us@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk-us
[Talk-us] CDPs and admin_level
In most states, municipal boundaries have been imported from TIGER data. In many of these states, no admin_level tag was used. That should be corrected (admin_level=8 for incorporated municipalities) but that's not the focus of this discussion. In the states where these boundaries were imported with admin_level=8, it appears that Census-Designated Places [1] were also included in the import, and treated the same as incorporated cities. (That's what happened in Ohio, anyway.) The wiki page [2] that lists what admin_level to use for various administrative units in different countries does not address Census-Designated Places. It does not say that CDPs should be admin_level=8, or any other value. I believe this should be addressed. Census-Designated Places are geographical units determined by the Census Bureau to give (arbitrary) limits to otherwise-unquantifiable, informal population centers. They do not represent any real political, governmental, or administrative unit. There are no signs posted to mark the borders of a CDP. Residents of a CDP usually are not even aware of its existence, though they are certainly aware of the informal population center it's meant to represent. They really have minimal real-world significance. You may be asking yourself, 'but how can I tell if something is a CDP or an actual city?' There are a few ways. For one thing, you could look up the locality on Wikipedia. CDP boundaries typically follow only roadway centerlines and sometimes county boundaries, whereas actual corporation limits can and usually do also follow property lines and the edge of the right-of-way on one side of roads. (More correctly, CDP boundaries don't split census blocks.) Finally, the answer may lie in the tags generated by the boundary import. For example, in Ohio, there's a tag like tiger:LSAD which always ends with CDP if the entity is a Census-Designated Place. I suggest using admin_level=9 or admin_level=10 for CDPs. If there is agreement here, then the wiki should be so clarified. (I don't think a full-blown proposal is necessary to make a minor clarification to an existing map feature, do you?) [1] http://en.wikipedia.org/wiki/Census-designated_place [2] http://wiki.openstreetmap.org/wiki/Tag:boundary%3Dadministrative#admin_level -- 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 Talk-us@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk-us
Re: [Talk-us] CDPs and admin_level
On Mon, Oct 12, 2009 at 9:52 AM, Greg Troxel g...@ir.bbn.com wrote: Another question is if these CDPs should be rendered on the default map; I'd say no. Would a renderer without special knowledge of admin_level render them or ignore them? Perhaps bogus arguments, but as a thought experiment I think they make the point that these regions are fundamentally different from what we think of as admin_level. (And thus worthy of a different tag.) Don't forget that admin_level is a border tag and not a region tag. Personally I don't think we should have mass imported the CDPs in the first place. In some areas they are useful. In other areas they aren't. They were created by the Census Bureau to deal with their particular needs, and I don't think those needs overlap enough with OSM. Where I live I'd prefer to use the neighborhood boundaries designated by my county property appraiser. I'm not sure if the Census Bureau used them for their CDPs or not. I've seen some pretty much match up, but I haven't done an exhaustive check. After the County/Parish/Borough level (which would be nice to move up a notch, painful though it may be), why don't we let each state work out the details? In New Jersey, it'll probably be a lot easier than in Florida, because New Jersey is 100% incorporated, while Florida is mostly unincorporated. These administrative regions differ greatly from state to state. Treating all of the US the same is nearly as bad as treating all of the EU the same. As an aside, I'd like to have property borders show up as a very light gray, similar to the way Google Maps now displays property borders in the US (the areas I've checked, anyway). Can I use admin_level=12 for that? Please, be kind, don't throw anything at me for making that suggestion. ___ Talk-us mailing list Talk-us@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk-us
Re: [Talk-us] CDPs and admin_level
On Mon, Oct 12, 2009 at 10:56 AM, Greg Troxel g...@ir.bbn.com wrote: So how about boundary=lot Fine with me. It's an issue I care about very little, it's one line of code to change. I believe that in Mass lot lines can straddle town boundaries - but I'm not 100% sure. However, now we're getting back on topic. Is that disallowed? Remember, these tags are placed on the borders, not the regions (which would typically be boundary relations), and remember that only the highest border is tagged. So if a single lot straddles two towns, that would be mapped with exactly the same borders as if there were two lots. The only difference would be in the boundary/multipolygon relation(s), which is not where admin_level is tagged. They are definitely not political boundaries though. I guess, though it's hard for me to come up with an objective definition of political boundaries which includes all the current uses and yet excludes this one. ___ Talk-us mailing list Talk-us@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk-us
Re: [Talk-us] CDPs and admin_level
I sympathize with Greg, and if the surveyors and computational mappers ruled the world, the real world we seek to model will be simpler. On Mon, Oct 12, 2009 at 12:44 PM, David Lynch djly...@gmail.com wrote: where city limits cross county lines, WTF? Where does that happen? down where a county is called a parish and is region within sound of a steeple? NYC inverts normal, iirc NYC is effectively a federation of city-counties called boroughs, but no county line crosses NYC boundary, right? When Boston adsorbed towns in adjacent counties, Suffolk county gained land too -- and likewise Boston and Suffolk released towns in the harbor to a non-adjacent (on land) coastal county. (as a result, Norfolk Co Mass is reputedly the only tripartite noncontiguous county separated by towns in other counties not by water ) If State and National electoral districts are included, the gerrymander boundary will assuredly cross, not follow, admin boundaries higher than Ward Precinct, which may be redrawn to convenience the gerrymander. -- Bill n1...@arrl.net bill.n1...@gmail.com ___ Talk-us mailing list Talk-us@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk-us
