Editor retention
I’ve been playing with the changeset data for OpenStreetMap and looking to see what patterns I can find in the usage of various editors since changesets were introduced in the API 0.6 migration. We can start off just looking at the major editors by distinct users, i.e: everyone’s favourite popularity contest.
If we look at the number of changesets by editor ordered by the number of distinct users, we get a pretty blindingly obvious result:
| Editor | Nc | Nb | Nu |
|---|---|---|---|
| Potlatch | 988916 | 739623 | 55941 |
| JOSM | 1092702 | 1043776 | 12945 |
| Merkaartor | 124756 | 117812 | 2100 |
| Mapzen POI Collector | 1374 | 1341 | 239 |
| BigTinCan Upload Script | 266 | 219 | 124 |
| iLOE | 1113 | 1019 | 105 |
| osm2go | 901 | 868 | 99 |
| Osmose Raw Editor | 756 | 358 | 82 |
| Mapzen Beta | 218 | 155 | 65 |
| bulk_upload | 60110 | 55417 | 61 |
Where Nc is the number of changesets, total. Nb is the number of changesets with bounding boxes, which usually means they represent real, geographic edits. Nu is the number of distinct users.
That’s not exactly a massive shock – Potlatch has the most users because it’s the editor on the OSM home page which requires the least effort to access. JOSM, somewhat surprisingly, has more changesets total and with bboxes, but maybe that’s just because until recently every upload was it’s own changeset. Merkaartor makes up the last of the “big three” editors with a couple of orders of magnitude more edits than than 4th place Mapzen POI collector.
Well, that didn’t tell us anything we didn’t already know. But how do editors compare at retaining their users? The following graph shows the number of users, logscale, against the length of time they’ve been editing over the past 6 months.
What does this tell us? Not a great deal — due to the growth of the OSM community there is always going to be a large number of users up-front and it’s not necessarily fair to assume they’re in the 1 month category, because they only joined a month ago. Correcting for this and normalising the results between the editors brings out the data much better:
Here we can see that they all show the same basic pattern — a user is most likely to use the editor for less than a month and then lose interest. Given that the same pattern is visible in all three editors it’s hard to say whether the editor itself has much effect on that, or whether these users just lose interest in OSM altogether.
The most striking difference is that a significantly smaller number of users continue to use Potlatch and Merkaartor after the first month (33% and 39% respectively) than JOSM (64%). Of course, this admits many explanations — it could be that JOSM is an editor which attracts users after the initial drop-out stage, or it could be an editor which persuades people not to drop out. The data could be made to support either…
11 comments December 4th, 2009