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Re: Plug and play alternatives to captcha

for

From: Moore, Michael
Date: Apr 17, 2008 10:20AM

Jared,

Thanks for your suggestions, you are preaching to the choir. I would
much prefer that the agency avoids the use of CAPTCHA all together but I
don't think that I am going to win that argument. In the mean time I
will test your suggestions.

I just tested re-captcha and found that though it "works" I still have
some serious concerns.

1. The only options are visual or audio challenges. Deaf/Blind are
excluded.
2. The audio challenge requires the listener to remember 8 numbers which
are announced over a background of conversation noise. In a quick
experiment with two highly proficient JAWS users we recorded a 50%
failure rate with 6 tries per user. Part of the problem was getting JAWS
to shut up at the beginning of the audio file but even after the users
knew what to expect the failures continued. Both users failed on their
first attempt. This method also poses concerns for people who have
cognitive disabilities in addition to blindness. This is not an uncommon
combination, I know two individuals who lost their vision due to head
injuries.

Mike