In the new draft OpenStreetMap Contributor Terms, an 'active contributor' is defined as:
a contributor (whether using a single or multiple accounts) who has edited the Project in any 3 calendar months from the last 6 months (i.e. there is a demonstrated interest over time) ...
This is a visualisation of the edits of the 8173 'active contributors' (as of 1/2/2010) across the last three years. For each contributor a mark is placed along a horizontal line under each day that they contributed an edit. At the top are contributors with almost daily edits (within the last six months) and, at the bottom, those that only just meet the criteria. The vertical axis has been scaled from 8173 to 1600 pixels. There is a fairly strong correlation between recent and historical edit intensities.
This was calculated from the planet changeset dump, and assumes that a changeset was edited on every day if it was open for more than one day (rare). It regards each user id as an individual, so does not take account of a contributor using multple user accounts.
rhodes added this photo to his favorites. (40 months ago)
Harry Wood 40 months ago | reply
I'm interested in the horizontal striations you can see in this image. These darker streaks represent users who were very active over a period. The streaks appearing lower down are users who were very active and have become less so. Of course these are the users who are still classed as "active". If the image carried on down to include all non-active users, we'd still see streaks for those unhappy cases where a user used to be active and now is not at all.
Why do the months seems to alternate darker and lighter? Can't think of an explanation for that.
ItoWorld 40 months ago | reply
The alternating months was intended to be a colour change to distinguish the months far down the image. Agree that it incorrectly appears to be a density shift.
Yes, the striations are the contributors who have decreased their activity. I've got a couple more images coming, one of which is the top 'inactive' contributors in order of their contribution in the past.
See: www.flickr.com/photos/itoworld/4361697501/