Handwriting analysis was pseudo-scientific to begin with. The payments market has to accommodate illiterate customers, disabled customers, and people who have a

Handwriting analysis was pseudo-scientific to begin with. The payments market has to accommodate illiterate customers, disabled customers, and people who have a broken hand at the moment. CC networks currently use previous purchasing patterns, location, time of day, etc. It's the same reasons why biometrics is not a magic security solution. Authentication must be based of something that's hard to fake, cheap to verify, random, and easy to change. What threshold would you set to balance false negatives and false positives? In comparison the private key in your chip card meets all of the criteria.