The answer is to teach the computer to find words and phrases that correlate and use tons of speed and memory to try out hundreds of different algorithms. If many of them give the same answer, Watson is more confident in the answer.
What makes language so hard for computers, Ferrucci explained, is that it’s full of “intended meaning.” When people decode what someone else is saying, we can easily unpack the many nuanced allusions and connotations in every sentence. He gave me an example in the form of a “Jeopardy!” clue: “The name of this hat is elementary, my dear contestant.” People readily detect the wordplay here — the echo of “elementary, my dear Watson,” the famous phrase associated with Sherlock Holmes — and immediately recall that the Hollywood version of Holmes sports a deerstalker hat. But for a computer, there is no simple way to identify “elementary, my dear contestant” as wordplay. Cleverly matching different keywords, and even different fragments of the sentence — which in part is how most search engines work these days — isn’t enough, either. (Type that clue into Google, and you’ll get first-page referrals to “elementary, my dear watson” but none to deerstalker hats.)What’s more, even if a computer determines that the actual underlying question is “What sort of hat does Sherlock Holmes wear?” its data may not be stored in such a way that enables it to extract a precise answer.
In essence, Watson thinks in probabilities. It produces not one single “right” answer, but an enormous number of possibilities, then ranks them by assessing how likely each one is to answer the question. ...IBM's ultimate hope: "Computers need to go from just being back-office calculating machines to improving the intelligence of people making decisions." The article discusses uses in medicine and making governments run better, particularly helping people sort through tax codes or other paperwork to find out if they qualify or what they need to do.
Ultimately, Watson’s greatest edge at “Jeopardy!” probably isn’t its perfect memory or lightning speed. It is the computer’s lack of emotion.
During one game, the category was, coincidentally, “I.B.M.” The questions seemed like no-brainers for the computer (for example, “Though it’s gone beyond the corporate world, I.B.M. stands for this” — “International Business Machines”). But for some reason, Watson performed poorly. It came up with answers that were wrong or in which it had little confidence. The audience, composed mostly of I.B.M. employees who had come to watch the action, seemed mesmerized by the spectacle.
Then came the final, $2,000 clue in the category: “It’s the last name of father and son Thomas Sr. and Jr., who led I.B.M. for more than 50 years.” This time the computer pounced. “Who is Watson?” it declared in its synthesized voice, and the crowd erupted in cheers. At least it knew its own name.
Hat tip: MR