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.

ENGADGET: Researchers use bioimpedance as a biometric, let health monitor devices know who you are

Not only does it use GPS co-ordinates for mobile telephony, but also refines its accuracy using cell masts to better locate a shop or restaurant in a large building.

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Some firms voluntarily did this in the past, but they did not have to guarantee its accuracy or face penalties.

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It had a troubled start but there have been frequent updates since to improve its accuracy.

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This measures not only the accuracy of a pitcher's arm but also its strength: The more victories a hurler has, the greater his endurance.

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But if the iPhone could process the data from its camera with the same accuracy as a human, it could drive your car.

FORBES: Teaching The iPhone To Drive: The Coming Singularity In Machine Vision

Not surprisingly given its designer, Carton is a shot-maker's course with its fairways not overly tight but rewarding of well-shaped shots which demand accuracy.

BBC: THE LOWDOWN

There are devices such as this one already in existence, but they are much larger than this new device, and its smaller size increases accuracy as it can be implanted closer to the spine than previous models.

ENGADGET: Chip implanted in spinal cord could help sufferers of chronic pain (video)

It follows a warning about accuracy from the exams watchdog, but the CCEA has only just given details of its mistakes.

BBC: exam pic generic