[Imports] Microsoft Buildings Import Inquiry

[Christoph Hormann]

On Monday 18 February 2019, Rory McCann wrote:
> > If you ask the mapper why they chose a particular tag or created a
> > particular geometry and they do not explain this with a particular
> > observation in reality or in an image source but ...
>
> This aligns with what I said IMO. "The mapper must approve it by OSM
> standards". If you add some data, you need to have grounds for it *by
> normal OSM mapping standards*. Which is local knowledge, aerial or
> survey.

Well- if for you it does that is great.  But it is somewhat tricky to 
assume everyone has the same understanding what "normal OSM mapping 
standards" are.  I therefore tried to put this on a somewhat less 
subjective basis.

> The Microsoft building outline dataset is very simple, containing
> only the outline of the building. No address, no height, no building
> type. no name. It can be (and was) derived 100% from aerial imagery.
> IMO if someone loads that up, and manually approves each building,
> then that (IMO) is much less of an import.

The dilemma here is that the reason why people do imports is to have 
less work than when manually mapping things.  But if you want to use 
external secondary data sources without actually doing an import you 
also loose most of the efficiency advantage (which results from not 
verifying everything feature by feature but blindly relying on quality 
of the source data in some way).

I am all for more mechanical support for mappers' work but fully machine 
generated data sets are simply not that useful here (outside the 
function of serving as a reference for finding missing features for 
example of course).  There are many interesting technologies that could 
support human mappers in more efficiently recording their local 
geography in OSM.  Replacing the mapper with bots and degrading the 
mapper for cleanup and verification work for bots is not an idea that 
has a lot of potential though (although having an 'openbotmap' project 
competing with OSM with such a paradigm would be interesting).

Regarding the Microsoft building data by the way we had a discussion 
regarding a possible import half a year ago which might be interesting 
to read for anyone considering to use the data either in or outside of 
OSM in some way:

https://lists.openstreetmap.org/pipermail/imports/2018-July/thread.html#5555

-- 
Christoph Hormann
http://www.imagico.de/