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  • NOVA scienceNOW

NOVA scienceNOW | Dark Matter, Of Mice and Memory, Hany Farid, Wisdom of the Crowds | PBS

Duration: 51:49 (Full Program)
Program: NOVA scienceNOW #301
Broadcast Date: Jun. 25, 2008

“Dark Matter”--Host Neil deGrasse Tyson reports from a half-mile underground in an abandoned mine, where scientists are using special detectors to look for evidence of a ghostly substance that they believe makes up most of the matter of the universe — a hypothetical entity called dark matter.

“Alzheimer’s/Memory Mice”--Researchers have found that mice with induced memory loss are able to retrieve memories either by being put into an enriched environment or by being given a drug that promotes beneficial gene activity in their brains. Such new insights may lead to a better understanding of dementia and other memory-impairment disorders, such as Alzheimer’s, in humans.

“Hany Farid”--Is seeing believing? In this age of easy photo manipulation, sometimes only a digital detective can tell. Enter Hany Farid, professor of computer science at Dartmouth College. He developed a program that can unmask photo tampering by analyzing light sources and other subtle features in an image — a service that turns out to be in high demand, especially during political campaigns.

“Wisdom of the Crowd”--Famed British scientist Sir Francis Galton (1822 to 1911), a proud aristocrat, thought he was proving the ignorance of the masses in his observation about a country-fair competition in which entrants were asked to guess the exact weight of an ox. The correct answer was 1,198 pounds; understandably, none of the 800 contestants got it exactly. “See!” said Sir Francis. “Decisions should be left to higher classes” — or sentiments to that effect. However, Sir Francis failed to realize that graphing all the guesses and determining their median produces the right answer and shows the “wisdom of the crowd.”

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Post Date: June 10, 2009