[Imports] Bing Building Import

[Christoph Hormann]

On Monday 02 July 2018, Greg Morgan wrote:
> I have started work on the Bing building import for Arizona us.  I
> have started this page here
> https://wiki.openstreetmap.org/wiki/Import/Catalogue/US/BingBuildings
> for the import.  This wiki page may be used by other mappers in
> different states.
>
> [...]

First thanks for bringing this up early in the process - although this 
is too early obviously for an import review it is good to have a broad 
discussion early.

A few points i would like to comment on:

* legal aspects:  Microsoft released the data under the ODbL but does 
not specify what data sources go into producing it (in particular 
training data!) and does not make any claims that the data is free of 
third party rights.  I would not be fine with importing data of unknow 
provenance and without a meaningful guarantee that it is free of third 
party rights.

* quality aspects:  In contrast to almost all other data sets where 
there is some quantitative specification of quality (either explicitly 
or implicitly due to the purpose the data set is created for) there is 
no indication of quality in what Microsoft has released beyond the 
vague and meaningless 'awsome quality' claims.  IMO this means that a 
proper import review would only be possible based on a thorough 
analysis of the quality of Microsoft's product that holds up to 
scientific scrutiny.

Regarding quality in general - you should not make the mistake of trying  
to assess quality by picking a few places and manually reviewing the 
data based on gut feeling - possibly with the same imagery used as 
reference as Microsoft used in data set generation.  What i 
called "analysis of the quality that holds up to scientific scrutiny" 
means picking a sufficiently large number of sample locations 
representative for the diverse geography of the US and doing a 
quantitative analysis based on reference data of known and high 
quality.

Microsoft's process documentation contains a number of hints that 
indicate things can go wrong in the process in ways that are likely to 
produce significant errors of kinds that are very unlikely to happen in 
manual mapping.  Without having reliable data on how often these things 
do happen (and how this varies between different geographic settings) 
you would essentially be doing a blind import.

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