[OSM-talk] Google fumbles again in latin america

[David Murn]

On Sat, 2010-11-06 at 22:58 -0400, Russ Nelson wrote:
> Apollinaris Schoell writes:
>  > I consider it improving osm by a human mapper according the spirit
>  > of the project instead a container full of imports with not much
>  > value. If a human surveys on ground or based on personal knowledge
>  > and image tracing it has 100 times more value than any imported
>  > data
> 
> I have some sympathy for your position, but I was told explicitly by
> the New York State Department of Environmental Conservation that their
> shapefile is to be considered primary over the signs in the field.
> Thus, mapping NYS DEC Forest Lands in the field is 0 times more value
> than their authoritative shapefile, which I've imported.

How do you know that the shapefile is correct, unless you survey on the
ground?  Just because their shapefile says a road travels 20m then turns
and travels 50m, if the actual road travels 30m then turns and travels
40m, it doesnt matter what they consider 'primary' or 'authoritive', if
its wrong.  Or for example if a map says a cliff is in position x, if
the cliff is actually in position y, you should correct that.

This whole thing of trusting the data before your own eyes/knowledge, is
what causes problems such as the Latin American issue discussed
recently.  I somehow think that if it came to a court, the on-the-ground
signs would be taken as a primary source, over some mystery government
coordinates.

If we're only talking about administrative boundaries, thats a different
story, as theres no easy way to verify that data on-the-ground, but just
because some government departments data says the sky is green and the
grass is blue, that doesnt mean it should be entered into the database,
if someone surveys it and finds its wrong, otherwise OSM simply becomes
a collection of other peoples unverified databases.

David