On my favorite page, http://meta.wikimedia.org/wiki/List_of_Wikipedias there is a column for "depth", which is "a rough indicator of a Wikipedia's quality, showing how frequently its articles are updated". Tomorrow that column has been there for two full years, with slight modifications of its formula. I wrote a separate page about this, http://meta.wikimedia.org/wiki/Depth (Note that this is completely unrelated to http://en.wikipedia.org/wiki/Wikipedia:Depth ) There has been a lengthy discussion on the good and evil of trying to estimate the quality of Wikipedia. But I think "depth" is the only measurement that we can track over such a long time. What other estimates of Wikipedia quality do we have, that can be applied across language versions? Erik Zachte's Wikipedia Statistics (last updated in May 2008) presents a number of values that could be used to calculate a quality estimate: number of articles, number of articles longer than 0.5 kbytes or 2 kbytes (excluding some markup), mean edits per article, mean bytes per article, number of edits (total), size of database in bytes or words, number of internal or interwiki or image or external links, number of redirects. The editing depth is essentially the number of edits divided by the number of articles (with two more factors in the formula). This means edit wars and repeated use of the save button (instead of preview) will give a higher depth. But if an article is made perfect before it is saved, it gives a low depth. Thus, "depth" measures the amount of editing activity within Wikipedia, as opposed to the real quality of the resulting article. This can be interesting in itself, but it might also be interesting to estimate the amount of interconnectivity between articles, where orphan articles or articles with just one link to them are discounted as a kind of stub. How can such a measurement be defined? If possible, by just combining the values we already know. Earlier (2005-2006), the Swedish language Wikipedia created many (mostly very short) articles, giving it a high ranking position in the list of Wikipedias (by article count). But since these stubs were created once and never touched again, this gave it a rather low "depth" of 14 (in November 2007). During 2008, a number of subprojects have gone back and made minor edits to many old articles, so the "depth" has climbed to 23. This is not high, but no longer among the very lowest. The increase by +64 percent is however overshadowed by the Turkish Wikipedia's increase by +125 percent (from 39 to 88). Also, the French Wikipedia has increased its depth from 58 to 113, while the German Wikipedia only moved from depth 68 to 80. -- Lars Aronsson (lars(a)aronsson.se) Aronsson Datateknik - http://aronsson.se