[HOT] Getting organised

john whelan jwhelan0112 at gmail.com
Tue Jan 5 14:24:25 UTC 2016

HOT is evolving, we started off with mainly experienced OSM mappers mapping
in response to short term emergencies.  Now do do a wider range of tasks
with a wider range of mappers.

We're seeing organisations such as MSF and the Red Cross guiding people who
want to help them to mapping with HOT, so our mappers are changing.  It
helps engage volunteers.

We're starting to see more GIS and mapping being organised locally but
still not as much as I'd like to see.  The locals are better at reading
street names than people mapping from imagery.

Currently http://tasks.hotosm.org/ is our splash page if you like.  At the
moment we see two or three high priority projects followed by medium
priority projects in date order, the most recent last.  So the medium
priority projects get their five minutes of glory then drift down into the
mass of medium projects.

We end up with a large number of projects that get 25% done, 5% validated
and drift on for years.

I suggest we have ten slots set at high priority, that way we stand a
chance of getting a few projects completed.

Of these I suggest that MSF, American Red Cross get given two permanent
high priority slots.  That would concentrate their minds on which of their
projects are most urgent.  At the moment I suspect mappers are seen as a no
cost resource and some projects that are still around where the ground
workers have finished their tasks but we're still mapping.

Of the others, I'd give three to other organisations for a period of say
three months.  For example Cameroon has a mapping department, Bangladesh
has an active community, Nepal again has an active community and there are
others.  Let them decide which projects will do them most good.  They may
make some mistakes but I hope it will develop a sense of ownership.

The other five I'd let the board decide.

Then we have the dead wood projects that clutter up the medium priority,
these are projects where no one has mapped or validated for more than a
month.  It maybe the imagery is poor, the instructions too complex, or
whatever.  I'd downgrade these to low priority, that way the active
projects would stand out more and again stand more chance of completion.

It might even be worthwhile having a weighting attached to each project,
the more active projects or highly validated projects move up the list the
less active ones move down.  It just needs a tag for the task list to
order.  The actual computation can be done off line say once a day and
someone else can sort out the algorithm.

Can we get more out of our mappers?

I think we can.  On project 1390 I validated as people mapped.  New mappers
got feedback, the advantage is they get a bit more involved and feel
engaged.  So we got more tiles out of them.  We got 6 or more tiles out of
a number of new mappers or ones who had mapped less than six tiles before,
typically I'd expect one or two tiles from them.  On the data quality side
I think it was up.  By correcting problems early on the new mappers made
less mistakes that need intervention later on from the validation side.
However it takes effort, the faster the feedback the better the results.

Validation is a tricky.  HOT isn't traditional OSM where individuals like
to map park benches or waste bins.  There is a service level to be met, and
if the building is five feet out, well that's probably good enough although
we  should strive for accuracy.  It's a bit lets get something useful done
with the resources we have.  Normal good management technique is catch them
doing something right.  So invalidating a tile is the last thing you want
to do.  I normally correct then leave a note, such as added fourteen
settlements. Where possible third party it JOSM validation picked up the
following: African wiki suggests higway=living street in an African small
village may not be appropriate and I must confess I normally delete any
zebra pedestrian crossing I come across in Africa.  There is another issue
with experienced OSM mappers HOT has its own conventions, such as
everything that looks like a building is mapped as an area and tagged
building=yes.  Some OSM mappers use a node tagged building=hut etc.  Giving
feedback is delicate because in the OSM world what they are doing is

The worst validation is by someone who has mapped two tiles.  I recently
double checked one and JOSM validation picked up a dozen problems and
visually there were a few more.  This is a data quality issue and it
becomes a matter of are any of the validated tiles to be trusted.  In Nepal
this was a major issue.

We don't have enough good tactful validators.

1390 was also interesting in that I came across an MSF volunteer, new
mapper who mapped accurately, did a fair number of tiles but when it was
complete wanted to know which MSF project to map next.  So project managers
need to have something in the pipeline.

Project managers need to understand the mappers.  We have more
inexperienced mappers than experienced ones.  Projects that demand only
buildings and have documentation on how to map them work well.  Projects
that ask for landuse=residential and connecting highways to be tagged
unclassified work well.  Ones that ask for forests, and everything else
don't work as well.  New mappers get confused and give up and take up
basket weaving instead which is not what we'd like.

Mapping should be fun.

Anyway there is enough to mull over.

Cheerio John
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