The Gambler Who Cracked The Horse-Racing Code

Bill Benter did the impossible: He wrote an algorithm that couldn’t lose at the track. A billion dollars later, he tells his story for the first time.

- Kit Chellel

Horse racing is something like a religion in Hong Kong, whose citizens bet more than anyone else on Earth. Their cathedral is Happy Valley Racecourse, whose grassy oval track and floodlit stands are ringed at night by one of the sport’s grandest views: neon skyscrapers and neat stacks of highrises, a constellation of illuminated windows, and beyond them, lush hills silhouetted in darkness.

On the evening of Nov. 6, 2001, all of Hong Kong was talking about the biggest jackpot the city had ever seen: at least HK$100 million (then about $13 million) for the winner of a single bet called the Triple Trio. The wager is a little like a trifecta of trifectas; it requires players to predict the top three horses, in any order, in three different heats. More than 10 million combinations are possible. When no one picks correctly, the prize money rolls over to the next set of races. That balmy November night, the pot had gone unclaimed six times over. About a million people placed a bet—equivalent to 1 in 7 city residents.

At Happy Valley’s ground level, young women in beer tents passed foamy pitchers to laughing expats, while the local Chinese, for whom gambling is a more serious affair, clutched racing newspapers and leaned over the handrails. At the crack of the starter’s pistol, the announcer’s voice rang out over loudspeakers: “Last leg of the Triple Trio,” he shouted in Australian-accented English, “and away they go!”

As the pack thundered around the final bend, two horses muscled ahead. “It’s Mascot Treasure a length in front, but Bobo Duck is gunning him down,” said the announcer, voice rising. “Bobo Duck in front. Mascot fighting back!” The crowd roared as the riders raced across the finish line. Bobo Duck edged Mascot Treasure, and Frat Rat came in third.