[Talk-us] Fresno castradal imports

[Frederik Ramm]

Brett,

On 05/04/2012 11:11 PM, Brett Lord-Casitllo wrote:
> Excuse me, but what is your foundation for declaring cadastral data
> "useless" in OSM?
> Where does it say that OSM is just for roads, addresses, and geocoding?
> As someone that uses OSM for disaster response, cadastral data, even
> outdated cadastral data, is a godsend when it is available.

The problem is that you are mixing up the questions of "is data useful 
generally", and "is data useful in OSM".

You can sure as hell make a very useful map by, say, firing up TileMill 
and taking an OSM base layer and overlaying the cadastral shapefiles 
from whatever disaster area you are working in. If these shapefiles are 
not readily available, then one should create some kind of repository or 
catalogue that makes them so.

That does not, however, mean that such data makes sense *in* OSM.

OSM is not a giant collection bowl for data ("oh look I've found a scrap 
of data on my city's web site, let's upload that to OSM so that it don't 
get lost!!!").

OSM is a giant *editor*. OSM is for *editing* data. OSM is not the GIS 
system to end all GIS systems. The huge strength of OSM is its 
community, the hundreds of thousands of hands who can and do help 
surveying data and keeping it current.

Anything that is surveyed and that can be updated by normal citizens can 
benefit from being in OSM; where people survey such data and put it in 
into OSM, they open the data up for the helping hands of others.

Data that is "administrative", and where usually the "master" database 
resides outside of OSM, is not suitable for editing in OSM, first of all 
because it usually cannot be observed on the ground (so nobody can 
survey reality, check data against it, and fix it where necessary), and 
second because it would make *no sense* to fix something in OSM when the 
authoritative source is elsewhere.

That's the reason why cadastral data is useless in OSM; it abuses OSM as 
a data distribution vehicle, it doesn't leverage that which is great in 
OSM (namely editing by anyone), and it clogs the system and makes it 
less useful for those purposes where OSM could show its full potential.

Bye
Frederik

-- 
Frederik Ramm  ##  eMail frederik at remote.org  ##  N49°00'09" E008°23'33"