[WikiEN-l] Looking for thoughts on statistics

[Gregory Maxwell]

On Sun, Mar 28, 2010 at 12:49 AM, Keegan Paul <kgnpaul at gmail.com> wrote:
> http://stats.wikimedia.org/EN/ChartsWikipediaEN.htm
>
> <http://stats.wikimedia.org/EN/ChartsWikipediaEN.htm>It's obvious of the
> peak in January of 2007.
>
> What I'm interested in is thoughts of why New Contributors has statistically
> declined sharply, but the list of active contributors has much less of a
> slope and even less so for very active contributors.
>
> What happened in the first six months of 2007?  Did we change template
> systems?  Did we reword some policies relating to new users?

Careful not to mistake a decline in the derivative of a function to be
a decline in the function. The number of new contributors _must_
decline at some point, unless you hold a hypothesis that Wikipedia
will eventually be driving the growth of human population. ;)

The step function in December 2005 is clearly due to
http://en.wikipedia.org/wiki/Wikipedia_biography_controversy#Wikimedia_Foundation_reaction

The only thing I recall happening around June 2007 was the
introduction of a real captcha.  Might be relevant if a non-trivial
amount of the new accounts were spambot sleepers!

I don't recall how those stats are generated. If they are produced
from the public data then there will be odd distortions due to
deletions hiding accounts..

I think there were also changes to the upload procedure around that
time (the interface language abuse for an upload wizard) which started
directing users to commons to upload... and uploading is a primary
reason to create an account.   This seems to be at least weakly
supported by the stats on commons:
http://stats.wikimedia.org/EN/ChartsWikipediaCOMMONS.htm

I'd guess that like most things its probably a mixture of weak effects.