Science
Notebook

Monday, March 5, 2007

Insight Into Soccer Strategy

You are a soccer goalkeeper, staring at an opponent about to take a penalty kick. You've got a big space to defend, and you know the odds of blocking the kick are slim -- typically less than 20 percent. Wouldn't it be great if you could influence the kicker's decision about which side of the net to aim at, so you'd be prepared to lunge in that direction?

Science to the rescue.

A new study concludes that by standing imperceptibly off-center, a goalie can nudge a kicker to kick toward the slightly larger space.

Researchers at the University of Hong Kong's Institute of Human Performance studied 200 video clips of penalty kicks from professional matches. They noted that even though goalkeepers stood, on average, four inches off-center -- creating a space difference of less than 3 percent on either side of them -- most kicks were aimed at the slightly larger space.

In additional tests with video monitors, using a scale model of the German goalkeeper Oliver Kahn shown in front of a goal, observers playing the role of the kicker were confident about which side the goalkeeper was closer to when the off-center difference was greater than 3 percent.

A third study, in which players were told to kick only if they believed the goalkeeper was exactly on center, found that people nonetheless kicked when the goalkeeper was off center by up to 3 percent -- and more often toward the imperceptibly larger side.

Best results come when the goalkeeper stands 2.5 to 4 inches off center -- a distance that increases the odds the kicker will aim at the larger side by more than 10 percent -- the team reports in the March issue of the journal Psychological Science.

-- Rick Weiss

Ancient Observatory Identified

The mysterious Thirteen Towers of Chankillo -- a line of ancient structures built on a small hill in the coastal desert of Peru -- have been identified as being the oldest solar observatory in the Americas. Constructed 2,300 years ago, they mark the risings and settings of the sun through the year when viewed from two newly excavated observation points nearby.

Research by archeologists from the University of Leicester and Yale University has established that the towers were at the center of a large ceremonial area, apparently used by ancient sun worshipers. At one observation point, excavators found pottery, shells and stone artifacts not found elsewhere -- suggesting that rituals took place on the site.

The Chankillo observatory predates by centuries the Incan and Mayan cultures, which led study author Ivan Ghezzi of Yale to conclude: "Chankillo reflects well-developed astronomical principles, which suggest the original forms of astronomy must be quite older."

The towers were built in a row at regular intervals. When Ghezzi and co-author Clive Ruggles, an authority on archeoastronomy, found the observation points a short distance to the west, they concluded that the towers were designed to help fix the time of sunrise and sunset throughout the year.

The research, published in Friday's edition of the journal Science, suggests that the monuments were a statement of power. Those who controlled the monuments, they said, were also seen to control the sun. The relationship between the monuments and political power is further reinforced by the fact that the observatory is near a heavily fortified hilltop structure with large walls, gates and parapets.

-- Marc Kaufman

Sex Doesn't Always Sell

Advertisers will sell more stuff if their commercials run during innocuous family-fare programs rather than sexually charged shows, suggests new research into the effects of erotic programming on viewers' response to ads.

Programs with overtly sexual content appeared to interfere with viewers' ability to remember the commercials, according to the study, published in the journal Applied Cognitive Psychology.

Researchers Ellie Parker and Adrian Furnham at University College London said provocative content may have left little "cognitive space" in viewers' brains to process the commercials.

The researchers brought volunteers into a laboratory to watch an episode of the comedy "Malcolm in the Middle" and an episode of "Sex and the City" called "Was It Good for You?" One program contained nudity and sex scenes; the other had neither. Interspersed in the programs, the researchers had viewers see different advertisements for cellphones, hair products and other everyday items. After the program, the volunteers were asked to recall as many advertisements and brands as they could.

"Brand recall for advertisements was 'hindered' by sexual content of programs, suggesting that there is something particularly involving or disturbing about sexual programs," the paper concluded.

In a separate part of the experiment, researchers tested how advertisements with sexual content affected viewers. They found that men had better recall of advertisements with sexual content and women had worse recall for those ads.

-- Shankar Vedantam