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Re: Alternatives for the CAPTCHA


From: Randi
Date: Apr 1, 2009 6:05PM

This is a little off topic, but I'm wondering if there's a Department
of Internet Security or anything? I mean people who are dedicated to
trying to destroy spam bots? If there was just some way of actually
making it impossible for them to even work, captchas wouldn't even be
needed. I mean, if Apple figured out how to never get viruses, can't
someone figure out how to destroy the bots before they can be
destructive? Am I just really naive?

On 3/23/09, Stephan Wehner < <EMAIL REMOVED> > wrote:
> On Mon, Mar 23, 2009 at 6:47 PM, Chris Hoffman < <EMAIL REMOVED> >
> wrote:
>> Why not flip the problem on its head, and ask, "What are people really
>> bad at that computers are good at?"
>> Then provide a problem that a computer algorithm would get _right_,
>> but that a human being would get _wrong_. Exploit the cognitive biases
>> that we have but computers don't.
>> Yet another approach would be to use natural language parsing
>> problems, which are very difficult for computers. For example, ask
>> "Which of the following is a valid English sentence: 'The dress Mom
>> bought Dad's sister fits' or 'The dress Mom bought myself fits' ?"
> The spammers would try three times instead of once, guess the valid
> sentence, and get through every three times
> on average: still far too often. This is the usual reason not to
> implement such a system.
> Stephan
>> --Chris