It seems that most spam seems to be by accounts and only a small
fraction by anonymous accounts. Still limiting edits to accounts would
reduce spam a bit.
When I set up the wiki I was told I needed to allow anonymous editing.
I think the spam would not be reduced too much by accounts -- most of the spam I delete is from a registered user. What did help on other wikis was requiring the email address provided at registration to be verified before being allowed editing rights. However setting this option would of course mean anonymous editing is unavailable.
I like the idea of making a simple question. For example, Ubuntu
forums force people to answer a question (such, "how much is 2+2" or,
"what's the color of an orange") before making a search, and I
remember seeing a question on savannah site about the number 1984 (the
question was what was the name of George Orwell book that is an year).
A simple question about octave seems to me the best way.
jwe said he was too busy atm with other things for wiki settings; maybe we can revisit this when he has some time.
I've been told this (having to answer a question) works okay on savannah -- no spammy bug postings. But the wiki (sepcifically, the mediawiki platform) is targetted a lot more heavily by spam bots, or maybe spam users. Computer OCR is already pretty good so but I suspect it would be thwarted by something very context dependent, so even if the question is easily read by a computer, the answer is not so obvious without the contextual information. But I guess we can test it out.
-Joanna