[OSM-dev] Why are so many changeset so large?

[Paul Norman]

> From: Alex Barth [mailto:alex at mapbox.com]
> Subject: Re: [OSM-dev] Why are so many changeset so large?
> 
> BTW, I did some cursory digging in the changesets dump and found that
> actually only a relatively small percentage of changesets are
> geographically large. Trying to use the history tab they seem to be more
> numerous. I don't have numbers yet, but I hope I can share some soon.

The issue is that you see every large changeset. This is most obvious in areas with no editing like the middle of the ocean. Looking at the size of an average changeset weighted by changeset size might produce data that comes closer to what you see in the history tab. The problem is then that you don't care about the history tab for most of the world, only where people or mappable features are.

Incidentally, it's possible to make a changeset that only touches a small area but has a larger bbox with the expand_bbox call - see http://wiki.openstreetmap.org/wiki/API_v0.6#Expand_Bounding_Box:_POST_.2Fapi.2F0.6.2Fchangeset.2F.23id.2Fexpand_bbox

I've never used it myself.