I guess now the question becomes what goes behind Watson’s immensely powerful intelligence system. Let’s dig up some history and try to unearth the answer.
Watson – Deep Dive
Watson is an artificial intelligence computer system capable of answering questions posed in natural language, developed in IBM's DeepQA project by a research team led by principal investigator David Ferrucci. Watson was named for IBM's first president, Thomas J. Watson. The program operates on POWER7 processor-based systems.
In 2011, as a test of its abilities, Watson competed on the quiz show Jeopardy!, in the show's first and only human-versus-machine matchup. In a two-game, combined-point match, broadcast in three Jeopardy episodes February 14–16, Watson bested Brad Rutter, the biggest all-time money winner on Jeopardy!, and Ken Jennings, the record holder for the longest championship streak. Watson received the first prize of $1 million, while Ken Jennings and Brad Rutter received $300,000 and $200,000, respectively.
In the match, all contestants, including Watson, had to wait until host Alex Trebek spoke each clue entirely, then a light was lit as a signal; the first to activate their buzzer button won the chance to respond. Although Watson suffers from cognitive deficiencies when analyzing the clue's contexts, it typically activated its button faster than its opponents. Watson also only had trouble responding to a few categories, such as short clues containing only a few words. For each clue, Watson's three most probable responses were displayed by the television screen. Watson had access to 200 million pages of structured and unstructured content consuming four terabytes of hard disk storage, including the full text of Wikipedia. Watson was not connected to the Internet during the game.
How does Watson compete on Jeopardy!
When playing Jeopardy!, all players, including Watson, had to wait until the host spoke each clue entirely, then a light was lit as a "ready" signal; the first to activate their buzzer button won the chance to respond. Watson received the clues as electronic texts at the same moment they were made visible to the human players. It would then parse the clues into different keywords and sentence fragments in order to find related phrases in terms of statistics. Watson's main innovation was not in the creation of new algorithm for this operation, but rather its ability to quickly execute thousands of proven language analysis algorithms simultaneously to find the correct answer. The more algorithms that find the same answer independently, the more likely Watson is to be correct. Once Watson has a small number of potential solutions, it is able to check against its database to ascertain if the solution makes sense. In a sequence of 20 mock games, human participants were able to use the average six to seven seconds that needed to hear the clue and decide whether to signal for responding. During that time, Watson also has to evaluate the response and determine if it is sufficiently confident in the result to signal. Part of the system used to win the Jeopardy! contest was the electronic circuitry that received the "ready" signal and then examined whether Watson's confidence level was great enough to activate the buzzer. Given the speed of this circuitry compared to the speed of human reaction times, Watson's reaction time was faster than the human contestants, except when the human successfully anticipated (instead of reacted to) the ready signal. After signaling, Watson speaks with an electronic voice and gives the responses in Jeopardy!'s question format.