A couple of comments, these are sort of related but not so scientific as
Martin's work:
First when you validate JOSM validation catches unclosed ways, (buildings
for example.) crossing ways, ie two highways that cross but don't have a
node so routing software won't know you can change from one to
After my talk at State of the Map in Brussels, Nick Allen asked: are newcomers
more likely to be retained if we give them positive validation feedback? I had
no answer at the time, but Tyler kindly gave me permission to look at the data
to find out. The resulting findings are now under peer
