Showing posts with label natural language processing. Show all posts
Showing posts with label natural language processing. Show all posts

Friday, February 18, 2011

Ken Jennings reflects on Watson

Ken Jennings, arguably the all-time champion at Jeopardy, has a great article on Slate. He reflects on his and Brad Rutter's match with Watson.
I expected Watson's bag of cognitive tricks to be fairly shallow, but I felt an uneasy sense of familiarity as its programmers briefed us before the big match: The computer's techniques for unraveling Jeopardy! clues sounded just like mine. That machine zeroes in on key words in a clue, then combs its memory (in Watson's case, a 15-terabyte data bank of human knowledge) for clusters of associations with those words. It rigorously checks the top hits against all the contextual information it can muster: the category name; the kind of answer being sought; the time, place, and gender hinted at in the clue; and so on. And when it feels "sure" enough, it decides to buzz. This is all an instant, intuitive process for a human Jeopardy! player, but I felt convinced that under the hood my brain was doing more or less the same thing.

Wednesday, February 16, 2011

Computers 1, Humans 0

One of the two Watson Jeopardy games has now been televised, and Watson won handily. Watson has $35,734, Rutter has $10,400, and Jennings has $4,800. Watson has more than twice the other two's scores combined. We'll find out tonight whether the computer can hold its lead.

It was an interesting match to watch. The audience was the most excited Jeopardy audience I've ever seen, and they were rooting for Watson. When he took a guess and got it right, there was a thunderclap of applause. When he had to make a wager, as with a daily double, they broke up laughing at Watson's odd-ball wagers such as $6,345.

The game was much closer than the score indicates. For many of the questions, all three contestants would know the answer, and it was a race to ring in the fastest. On many of them, if Watson had needed six seconds rather than five to figure out its answer, a human would have rung in first.

One thing I was surprised about was the Final Jeopardy question. The category was "U.S. cities", and I thought Watson would knock it out of the park. I thought it would bet high and answer it easily. The opposite was the case. The computer had no idea what the names of airports mean. Apparently, even with all the time contestants are given for Final Jeopardy, it couldn't connect the dots from "World War II" to "O'Hara" and "Midway". Yet, it still did okay in the end, because it only bet about $1000 on the question. Did it bet so low because of the category, or did the programmers have Watson be categorically cautious in Final Jeopardy?

I don't know, but one thing is clear. Humanity has met its trivia overlords, and they're made of silicon. This game show duel is just a spectacle, but take a moment to look what it means for the future. The way Watson is competing ultimately relies on a large, natural-language database. Unlike with Cyc or the Semantic Web, the computer doesn't need humans to explicitly re-encode information into a machine-friendly synthetic language. It is directly using the natural-language texts we wrote for communicating among ourselves.

The applications are far-reaching. At the simplest, Watson hints at greatly improved web searching, both when looking for pages and when looking for information. Other applications are in medicine. Imagine a Watson that had read a hospital's case files and a medical school's entire library, including the latest journal articles? No doctor can match that. For knowledge workers in any domain, imagine how much it would help to have a personal Watson that had read every email the person had ever sent or received? Natural-language processing has just passed a tipping point.

More about Watson is available on the Jeopardy web site.