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Science Notes: Computer knows when to hold ’em; secretive songbird finds a new home

Computer knows when to hold ’em

It has been eight years since a computer program “solved” checkers, calculating a strategy so optimal that it guaranteed at least a draw. Now, an algorithm has done the same for poker, producing a winning strategy that researchers say no human can beat in a single lifetime.

For computer scientists, poker presents a much more complex challenge than games like checkers or tick-tack-toe, in which every player is aware of every previous move. In poker, players don’t know what cards their opponents have been dealt, making it an imperfect information game. Such a variable, to say nothing of bluffing, makes the game far more difficult for a computer to pin down.

But researchers at the University of Alberta in Edmonton developed an algorithm that manages data in unique ways, allowing it to take into account more of the variables. The result is a formula for mostly winning a variation of the game called Limit Texas Hold ’em.

“If the dealer is changing back and forth, it’s possible to guarantee we don’t lose any money,” said Michael Bowling, lead author of the study. “And if the other guy makes some mistakes, it’s possible we may win some.”

Bowling and his colleagues, who published their work in the journal Science, have built a website where anyone can see how the algorithm would play specific hands.

Secretive songbird finds a new home

Swainson’s warbler – a secretive, rarely seen songbird that nests in the swamplands of the southeastern United States – may no longer be so hard to find. Researchers report that the bird has found a new safe haven: private pine plantations.

“I found hundreds of warblers breeding in pine plantations across 10 states,” said Gary Graves, an ecologist at the Smithsonian’s National Museum of Natural History, who led the study. “These warblers are encountering a new ecosystem – a man-created ecosystem.”

The study, which appears in the journal Bird Conservation International, suggests that by the end of the century, a majority of Swainson’s warblers will breed on pine plantations.

The birds arrive in the Southeast in April, nesting and breeding in swampy regions until it is time to fly south again in September. They like dense thickets, which can be found not just in swamps but among young pine trees, Graves said.

To track the warblers, he broadcast playbacks of their territorial song on plantations, monitored the responses and found breeding warblers in nearly 40 million acres of plantations from eastern Texas to southeastern Virginia.

“Before the 1920s there was no such thing as industrial pine agroforestry,” he said. “Birds and mammals and all sorts of creatures are now being exposed to this.”

– New York Times