[HOT] Data quality in Ecuador

[john whelan]

The good news is it’s a lot better than Nepal was.  I think most of that’s
down to better training guides so well done training.

In Nepal we saw a lot of tiles marked done or validated when there was
still a lot to do.  So in Ecuador if there are more than two or three
buildings missing I’ve been invalidating the tile.  In JOSM if you search
for buildings they highlight and it makes it easier to spot the missing
ones.  Some tiles have been invalidated three times.  The tiles are still
being mapped faster than I can validate them even though for the most part
I’ve been ignoring the JOSM validation warnings.  I’ve been concentrating
on the pink zones.

I’ve been briefed that it only takes five clicks to map a building in iD,
the four corners then “s” for square.  I suspect it also needs a tag for
the area, so say six clicks.  With JOSM building_tool plugin it takes three
clicks of the mouse, so if you’re mapping for more than an hour allowing
fifteen minutes to install JOSM and configure it you’ll get more buildings
out of the mappers.  The only thing I care about is the quality is higher.

I’ve seen less than a hundred area=yes rather than building=yes, this is a
vast improvement.  Trouble is it takes time to go and inspect them just in
case it isn’t a building.

I’ve seen maybe a hundred double mapped buildings.  Again because I haven’t
taken the time go through the crossing building warnings there maybe more
in there.

I’ve seen one or two mappers map but not tag.  These need going through
with the todo tool in JOSM to work out the tags which takes time.

A big problem has been highways, not touching or crossing.  Also in Africa
we have the wiki for guidance use highway=path rather than footway but I’m
unaware of anything for Ecuador.  My suggestion would be split the projects
into buildings and a separate projects for highways.  Highways need a
higher level of skill or different training.  MSF have used this approach
successfully.

Squared buildings? What can I say many aren’t.  I’ve also seen several
hundred mapped as building=house rather than building=yes.  JOSM
building_tool takes this decision away from mappers.

I haven’t gone over each building.  Sounds an odd thing to say but I’ve
seen several mappers grouping buildings together and tagging them
building=yes.

Larger buildings that look industrial often seem to be overlooked.  If
people were working in there at the time of the earthquake they are of
interest and looking at damage again I suspect they are of interest.

So thanks to those mappers who have been giving TLC to buildings, I think
we’re doing reasonably well but if you have JOSM and can recognise a
missing building please invalidate a few tiles.

Cheerio John
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