Do a reverse check

[joostschouppe]

We are checking if all roads in the REF data are also in OSM.

We also need to check if all roads in OSM are in the REF data. In many cases, doing so leads to corrections in OSM, especially with regards to improving geometry. In most cases, REF data is probably wrong.

What I would suggest is we do not do this yet. Let us ask REF data management to do this. We can offer training. They can then give the job of validating REF data to anyone, not just GIS professionals. The people doing it, will fix a lot of OSM errors, but will mostly be giving detailed feedback to REF data management. By doing this together with the REF people, we can shape the output so that it becomes directly useful to management. We can do this with something similar as what I describe here, however then the second line mappers are REF data management GIS professionals, not advanced OSM volunteers.