How to deal with a "low quality" armchair mapper?

First off: I don’t want to expose them or flame; this was the most accurate title I could think of.

While browsing through OSMCha, I have encountered a new mapper (registered ~3 months ago); they map mostly in less-mapped areas with lots of scattered buildings and low-res imagery. They seem to use the standard iD+Bing combo.

The mapping quality isn’t really up to OSM standards:

  • Building outlines are drawn very roughly (not rectangular, areas oftentimes twice as large, not aligned with the imagery, …)
  • Fantasy buildings are drawn (due to bad imagery?)
  • Real buildings are not mappped

So far, so okay. We all were newbies once and this happens. I have reached out to them via CS comments and shared some tips.

The problem:

Even though the user was created 3 months ago, they already have approx. 1000 edits with many new buildings created per edit (sometimes 100, sometimes 999). :face_with_spiral_eyes:

Depending on their answer, they might change their future mapping behaviour. I do believe that they are motivated and willing to learn (every CS tagged review_requested).

But what about the past edits? They are quite problematic. Should they be all reverted? But that might be very demotivating for them. Manual inspection is far too tedious though. I can’t (don’t want to) review 1k changes.

What to do now?

My general take on this, is that the mapper in question should fix their own mistakes, and if they are really interested in OSM that shouldn’t be an issue. So you should first point out what the problem is with the edits and then how best to fix the problems.


From what you’re describing (not rectangular buildings, missing buildings) sounds to me the user uses some kind of AI recognition without checking the automated results.
As @SimonPoole wrote: Try to contact the user and tell him about your concerns.


That sounds reasonable, thank you!

That is what I first thought as well but: It is kinda too bad for AI :eyes:.

Anyways, they don’t use rapiD or something, so they would have to import it manually into iD, which I doubt they do.

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First things first, talk to them about it (I believe that you’ve already done that). Where something is likely the first interaction with the rest of the OSM community that they:ve had, I’d always try and write things in a way that invites a reply - try and ask questions, for example. I’d also give them a few days to reply.


Absolutely, your perspective on the importance of user engagement and support within OpenStreetMap (OSM) is well-founded.