using the Turing test to stop bad people
Dec. 14th, 2012 05:33 am![[personal profile]](https://www.dreamwidth.org/img/silk/identity/user.png){kind=small}
miriam_eWe've all been on websites where we've had to enter words and numbers into Captcha (Completely Automatic Public Turing Tests to Tell Computers and Humans Apart) gadgets to prove that we're a human and not a spammer's robot. Well, now there is wonderful news. A new CAPCHA system has been developed that uses our empathy instead of relying only on our amazing ability to read distorted letters. The thing I find hilarious is that it will not only help protect sites from spammer-bots, but also from sociopaths.
The system is already available for use from:
http://captcha.civilrightsdefenders.org/
Of course this is still only a stop-gap. Spammers now employ humans at very low wages to do their dirty work, and empathy-based CAPCHA probably won't stop them. I doubt it will until we have tools to test comprehension -- that is, a way to find out if you understand the information on a page. A person who wants to comment or log in would already have read and understood it, but it would slow human spammers because they'd need to read the pages in order to answer questions, thus hopefully making their work uneconomic.
Most of these CAPCHA systems use images of words that are deliberately made difficult or impossible for machines to translate. This has one giant drawback that has largely been ignored: it makes such sites unusable for blind people who must use computer translation to audio for browsing sites. A test for comprehension would be more effective there.
The system is already available for use from:
http://captcha.civilrightsdefenders.org/
Of course this is still only a stop-gap. Spammers now employ humans at very low wages to do their dirty work, and empathy-based CAPCHA probably won't stop them. I doubt it will until we have tools to test comprehension -- that is, a way to find out if you understand the information on a page. A person who wants to comment or log in would already have read and understood it, but it would slow human spammers because they'd need to read the pages in order to answer questions, thus hopefully making their work uneconomic.
Most of these CAPCHA systems use images of words that are deliberately made difficult or impossible for machines to translate. This has one giant drawback that has largely been ignored: it makes such sites unusable for blind people who must use computer translation to audio for browsing sites. A test for comprehension would be more effective there.
no subject
Date: 2012-12-14 01:46 am (UTC)I've seen some very nice screening systems that ask a simple question like "Adding 5+4 gives what number?" however if everybody started using them spammers would quickly be able to program computers to circumvent them.
I've often thought something like, "Find the paragraph above that begins with 'Most'. Now type in the fourth word of the second sentence in that paragraph." In that case you'd type in "giant". It is simple and easy to program, non-repeating, can't be easily solved by computers, doesn't use distorted images of words so blind people could solve it, and would require human spammers to spend enough time on each page to hopefully render their work less economically viable.
Other ways to test for humanness would be to ask things like: "What animal flies at night and whose name rhymes with 'cat'?" or "What three-letter word begins with 's', ends with 'a' and has 'e' in the middle?" or "If you painted a chair with blue paint, what color would the chair now be?"