[Talk-us] identifying TIGER deserts

[Michal Migurski]

Some context for the query below:
	https://gist.github.com/4291608

I've been using this projection for everything, a spherical Albers to make it possible to generate a slippy map in a conic projection:
	+proj=aea +lat_1=29.5 +lat_2=45.5 +lat_0=23 +lon_0=-96 +x_0=0 +y_0=0 +a=6378137 +b=6378137 +nadgrids=@null +units=m +no_defs

-mike.

On Dec 14, 2012, at 9:47 PM, Michal Migurski wrote:

> Are you guys using the way version number to determine TIGERness? This from Andy Allan might be more effective:
> 
>    --
>    -- TIGER edits case statement from
>    -- https://github.com/MapQuest/TIGER-Edited-map/blob/master/inc/layer-tiger.xml.inc
>    --
>    (case when osm_uid = '7168' -- DaveHansenTiger
>                and osm_timestamp::timestamp >= '2007-08-03'::timestamp
>                and osm_timestamp::timestamp <= '2008-05-04'::timestamp
>              then 0
>          when osm_uid = '15169' -- Milenko
>                and osm_timestamp::timestamp >= '2007-10-29'::timestamp
>                and osm_timestamp::timestamp <= '2007-12-12'::timestamp
>              then 0
>          when osm_uid = '20587' -- balrog-kun
>                and osm_timestamp::timestamp >= '2010-03-21'::timestamp
>                and osm_timestamp::timestamp <= '2010-04-08'::timestamp
>                and osm_version::int < 3 -- maybe someone else edited between import and name expansion
>              then 0
>          else 1 end) as is_touched
> 
> Number of distinct users who've edited in a given area would also be a useful metric, though incomplete without reference to the full history file.
> 
> -mike.
> 
> On Dec 14, 2012, at 7:45 PM, Alex Barth wrote:
> 
>> 
>> Before I log off for tonight, let me share this screenshot I just got from Ruben (cc'ed) showing his progress on creating a slippy TIGER deserts map, pretty much using Martijn's approach of binned average geometry versions. These are first steps and there are still some math problems to iron out, expect an update next week. 
>> 
>> http://cl.ly/image/0x3h0s1H1v0k
>> 
>> On Dec 7, 2012, at 1:00 PM, Ian Villeda <villeda at mapbox.com> wrote:
>> 
>>> 
>>> Hey team, 
>>> 
>>> Over here at MapBox we were inspired by Martjin's great post on identifying TIGER deserts[1], so we're attempting to effectively identify TIGER deserts for the rest of the continental U.S. (sorry Hawaii + Alaska, you're next). The goal is to create a slippy map from zoom level 2 to 15(?) such that it's easy to find the places in need of the most love.
>>> 
>>> We have a osmium-genereated postigs database with all ways tagged as highway=* and their version number. The plan to run the analysis against a 5x5 km grid, although we will probably play with the size of the gridcell. Another option might be to conduct the analysis and varying levels of granularity. 
>>> 
>>> We're still consiering different methods of analysis - the goal being to normalize way density to display better identify TIGER deserts. We'd would love your thoughts / input / reactions. A few ideas we've tossed around / are activley pursuing:
>>> 
>>> - percent of version 1 and/or 2 ways in each gridcell
>>> - average number of version 1/2 ways per gridcell
>>> - using a threshold value(s) similiar to Martjin's approach
>>> - [your ideas here]
>>> 
>>> Ultimately we'd like showcase the rendered results in site that would make editing TIGER deserts easy. For now though this is just a heads up and an invitation if you have any thoughts on how better to identify TIGER deserts. 
>>> 
>>> thanks! 
>>> 
>>> [1]: http://oegeo.wordpress.com/2012/10/21/binders-full-of-tiger-deserts/
>>> -- 
>>> ian villeda
>>> mapbox | developmentseed
>>> https://twitter.com/ian_villeda
>>> 
>>> 
>>> _______________________________________________
>>> Talk-us mailing list
>>> Talk-us at openstreetmap.org
>>> http://lists.openstreetmap.org/listinfo/talk-us
>> 
>> Alex Barth
>> http://twitter.com/lxbarth
>> tel (+1) 202 250 3633
>> 
>> 
>> 
>> 
>> 
>> _______________________________________________
>> Talk-us mailing list
>> Talk-us at openstreetmap.org
>> http://lists.openstreetmap.org/listinfo/talk-us
>> 
> 
> ----------------------------------------------------------------
> michal migurski- contact info and pgp key:
> sf/ca            http://mike.teczno.com/contact.html
> 
> 
> 
> 
> 
> _______________________________________________
> Talk-us mailing list
> Talk-us at openstreetmap.org
> http://lists.openstreetmap.org/listinfo/talk-us
> 

----------------------------------------------------------------
michal migurski- contact info and pgp key:
sf/ca            http://mike.teczno.com/contact.html