After suffering its first defeat in the Google DeepMind Challenge Match on Sunday, the Go-playing AI AlphaGo has beaten world-class player Lee Se-dol for a fourth time to win the five-game series 4-1 overall. The final game proved to be a close one, with both sides fighting hard and going deep into overtime. AlphaGo is an AI developed by Google-owned British company DeepMind, and had already wrapped up a historic victory on Saturday by becoming the first ever computer program to beat a top-level Go player. The win came after a "bad mistake" made early in the game, according to DeepMind founder Demis Hassabis, leaving AlphaGo "trying hard to claw it back." By winning the final game despite its blip in the fourth, AlphaGo has demonstrated beyond doubt its superiority over one of the world's best Go players, reaffirming a major milestone for artificial intelligence in the process. It was "the most mindblowing game experience we've had so far," said DeepMind founder Demis Hassabis at the post-match press conference, with an "incredibly close and tense finish." Lee said that he felt sorry the match was coming to an end, while expressing how difficult it has been from a psychological perspective.

Go master Cho Chikun triumphed Wednesday in his final game against DeepZenGo, a Japanese artificial intelligence system, to win the three-game series 2-1. Cho, 60, has won 74 titles, the largest number in Japan, over a long career. He defeated DeepZenGo with the 167th move in the third game of the series, which was played on even terms with no handicaps. DeepZenGo uses deep learning and other advanced technologies. It is being developed with support mainly from Dwango Co., a video-sharing website operator, and the University of Tokyo. "I felt as if I was playing with a human, because (DeepZenGo) has both strong and weak points," Cho said after the final game.

Go master Cho Chikun triumphed Wednesday in his final game against DeepZenGo, a Japanese artificial intelligence system, to win the three-game series 2-1. Cho, 60, has won 74 titles in his long career, the largest number in Japan. He defeated DeepZenGo with the 167th move in the third game of the series, which was played on even terms with no handicaps. DeepZenGo uses deep learning and other advanced technologies. It is being developed with support mainly from Dwango Co., a video-sharing website operator, and the University of Tokyo. "I felt as if I was playing with a human, because (DeepZenGo) has both strong and weak points," Cho said after the final game.

After winning the first of a three-game go match against DeepZenGo, a Japanese artificial intelligence system, master Cho Chikun lost the second. DeepZenGo, developed mainly by the University of Tokyo, Dwango Co. and the Nihon Ki-in, the main organization in Japan for the traditional board game, has become the first Japanese program to beat a professional go player without the benefit of a handicap. On Sunday, the AI program defeated Cho, 60, who has garnered a Japan-leading 74 titles, in the 179th move of their game at a Tokyo hotel, leveling the score after its loss to the human master the previous day. The final game is to be held Wednesday at the Nihon Ki-in in central Tokyo. That's all I can say," said DeepZenGo developer Hideki Kato, 62. "I had the impression that Master Cho was a little short-tempered today.

All those cars on California's famously gridlocked highways could be doing more than using energy. They could be producing it. The California Energy Commission is investing 2 million to study whether piezoelectric crystals can be used to produce electricity from the mechanical energy created by vehicles driving on roads. The commission is choosing a company or university to take on small-scale field tests. It will study how the small crystals, which generate energy when compressed, could produce electricity for the grid if installed under asphalt.

Elon Musk said SpaceX successfully tested its Raptor rocket engine that might one day be used to transport people to Mars. SpaceX "achieved first firing of the Raptor interplanetary transport engine," Musk said Sunday night on Twitter. The engine is powered by methane and liquid oxygen. The disclosure came on the eve of Musk's scheduled appearance Tuesday at the International Astronautical Congress in Guadalajara, Mexico, where he is expected to discuss SpaceX's efforts toward eventually reaching Mars. Musk is chief executive of Hawthorne-based SpaceX, a privately held company whose full name is Space Exploration Technologies Corp.

Suddenly the era of driverless cars seems very near indeed. Uber began testing driverless cars in Pittsburgh last week, and this week, the Obama administration endorsed the push to develop these vehicles. Adding to the momentum, Ford and BMW say they will produce autonomous cars by 2021. Driverless cars will create some big winners -- imagine how Uber's and Lyft's profits will jump when they can keep 100% of fares instead of letting drivers keep 70%. But they will produce some big losers too, notably the 5 million people nationwide -- including 600,000 in California -- who make their living driving taxis, buses, vans, trucks and e-hailing vehicles.

Sales of new homes retreated in August, one month after surging to the highest level in nearly nine years. Activity fell in all regions of the country except the West. New home sales dropped 7.6% last month to a seasonally adjusted annual rate of 609,000 units, the Commerce Department reported Monday. That followed a surge in sales in July, when they jumped 13.8% to a rate of 659,000, the fastest pace since October 2007. Sales had been expected to slow after the July surge.

U.S. stocks are slumping in Monday morning trading as healthcare companies and banks take the biggest losses. Energy companies are inching higher as oil prices rise. Major indexes in Europe and Asia are also starting the week on a steep skid. The Dow Jones industrial average was down 108 points, or 0.6%, to 18,153 as of 10:15 a.m. The Standard & Poor's 500 index fell 10 points, or 0.4%, to 2,155.

Nine people were shot and wounded, one critically, in a Houston neighborhood Monday morning by a lawyer who had issues with his law firm, authorities said. The first report of the shootings began at about 6:30 a.m. CDT, Police Chief Martha Montalvo said at a news conference, and when officers arrived, the suspect began firing at them. Police shot the man, whom Montalvo did not identify and who later died at the scene. Numerous weapons were found at the scene, Montalvo said, and a bomb-squad robot is looking at a Porsche that's believed to be the shooter's.