For now, the researchers have created an eight-electrode proof-of-concept bracelet, but its accuracy leaves something to be desired -- it correctly identifies its wearer only 80 to 90 percent of the time, whereas fingerprint recognition has a failure rate of less than 1 in 1, 000.

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When a human wearing the EEG cap was introduced, the number of false alarms dropped to only five per hour, out of a total of 2, 304 target events per hour, and a 91 percent successful target recognition rate.

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People like Warren Buffett and Mitt Romney do a lot of their wealth building not because they pay a lower rate, but because they avoid gain recognition altogether.

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That might not seem a big percentage, but the hit rate will get better as face-recognition software improves and more snaps are uploaded.

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