“A supercomputer that soundly thrashed two of humankind’s most successful players at their own game.”

“What is Watson?”

Yes, after taking a strong lead after day two, IBM’s machine took a resounding win at the end of the third and final day of its Jeopardy challenge. Final score: Watson $77,147, Ken Jennings $24,000, Brad Rutter $21,600.

There were only two situations where the human players showed signs of superiority. The first came in the early questions of day three where Jennings and Rutter appeared to conclude that a round about movies was straightforward enough that it was safe to buzz in immediately and then use the few seconds before their required response to figure out the puzzle. That proved just enough to outdo Watson, which was programmed to (albeit it at a rapid pace) both figure out the answer and decide whether it was worth buzzing in.

The second situation arose on the final question when Jennings, as well as writing the correct answer, wrote “I, for one, welcome out new computer overlords.” Not having been programmed for improvisation, Watson failed to give the correct response of “What would be the best Simpsons line to quote right now?”

Meanwhile IBM has given more explanation about Watson’s incorrect answer of Toronto in a US Cities round. As well as noting the confusion about the Blue Jays playing in the American league, it blamed two further factors. Firstly, there are several smaller cities named Toronto in the United States. Secondly, analysis of previous games suggests that the title of a round doesn’t always match the questions perfectly: in this case Watson failed to distinguish that “US Cities” is indeed a precisely defined group.

If you want to know more about the Watson project, Stephen Baker (whose analysis we referred to yesterday) has released a book about it entitled Final Jeopardy: Man vs. Machine and the Quest to Know Everything. In a creative use of digital publishing technology, it went on sale in e-book form last month, with a final chapter — covering the TV showdown — released as a free update last night.