[OSM-talk] Why the HOT obsession with low quality buildings in Africa ?

[Jean-Marc Liotier]

On Mon, July 2, 2018 1:26 pm, Robert Banick wrote:
> Many humanitarian groups use buildings as a rough proxy for population

Yes, I have had that explanation from multiple sources involved in
humanitarian uses of Openstreetmap: from that they can calculate, for
example, the impact a a flood.

I believe that it is an awfully expensive way to gather that data.

A landuse=residential with a density qualifier may do the trick cheaply
with the addition of a density qualifier attribute: single family houses,
sparse multi-tenant buildings, dense multi-tenant buildings... This is
actually the data model used by the government of Senegal at their
national level with a street-level granularity.

If one wants to go further and count the number of dwelling units, then a
node is sufficient (maybe along with an attribute to discriminate single
or multi-tenancy)

Shapes are of course good for many other uses but, if the actual user
requirement that data is gathered for is a population density map, then
they are a waste of resources. I'm pretty sure that contributors are
happier if their efforts are directed at profitable purposes.