Has anyone come up with a formulae for the ratio between vandalism prevented by the edit filters and lost edits on Wiki? I'm trying to work out whether the "true" editing level on the English Wikipedia and others which use the edit Filters has risen or fallen since the Edit Filters were introduced in 2009. It turns out that this is a complex question, partly because the way that vandals respond to the edit filter is different to the way they respond to reversion and warning on wiki, and of course the filters have steadily got more complex and effective over the last four years. Also different filters will have a different ratio between vandalism filtered out and vandalism (and vandalism reversion, warnings, AIV reports and block notices) "lost" from Wikipedia. It would be great if we could simply assume that someone who in 2013 tries to vandalise five articles but is prevented by the edit filter would pre 2009 have made 5 vandalism edits that would have been responded to with five reversions, four warnings, one AIV report, one block message 0.01 barnstars and 0.3 archive edits on the AIV page. But it isn't that simple, not least because of the psychology, just as teenage vandals are probably less likely to persist if they discover that the person they are competing with is some grey haired pensioner; so in theory fighting against a computer that is faster than you is less satisfying than doing so against a fellow human. So I was wondering if there are Wikipedia language versions that have not yet implemented edit filters, or where the filters have changed so little that there are long periods where any change in editing levels has not been caused by improvement in the filters. This is of more than academic interest, if we simply ignore this effect and make decisions based on the remaining raw edits after the edit filter, then the more efficient the edit filter gets at preventing vandalism the more we would be beating ourselves up for losing edits. Regards Jonathan Cardy