pam filters block all messages containing the word 'vitamin,' but fail to block messages containing the word B12. If the program never saw B12 before, it's just a word without any meaning. But you would know it's a vitamin," Markovitch said. "With our methodology, however, the computer will use its Wikipedia-based knowledge base to infer that 'B12' is strongly associated with the concept of vitamins, and will correctly identify the message as spam,"
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