“With a 60% accurate classifier, the probability of solving a 12-image Asirra challenge is only about 0.2%.”
About This Quote
The Asirra challenge is an image based CAPTCHA where the user has to identify 12 images of dogs vs. cats in under 30 seconds to gain secure entry into a protected resource. Humans are really good at this task and as mentioned earlier in the paper can correctly identify with a 99.6% success rate.
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