Wednesday, October 24, 2012

'No offense to anyone,' except women scientists

Karen Rommelfanger, program director of the Neuroethics Program at the Emory Center for Ethics, wrote an opinion piece for the Chronicle of Higher Education. An excerpt:


"What does it mean when a highly successful neuroscientist … states that he is disappointed there aren’t more “super model types” at a major conference? Here’s what he wrote:

My impression of the Conference of the Society for Neuroscience in New Orleans. There are thousands of people at the conference and an unusually high concentration of unattractive women. The super model types are completely absent. What is going on? Are unattractive women particularly attracted to neuroscience? Are beautiful women particularly uninterested in the brain? No offense to anyone. 

"There are some who will say that it is no surprise, given the large number of attendees (30,000 plus), that an ugly statement appeared on an individual’s Facebook page. Some might say it’s inevitable, and perhaps inconsequential, given how large the membership is, that you will find a bad seed. But dismissing [his] comments would be a mistake and represents part of the problem for women."

Click here to read the full article.

Related:
Academia's female brain drain 

Tuesday, October 23, 2012

Election markets take stock of presidential race

If buying shares in an election market sounds like online gambling, that's because it is, says economist Monica Capra. (Emory photo/video.)

By Kimber Williams, Emory Report

Ever wonder how a presidential candidate's stock is trading?

As voters weigh the odds of their candidates prevailing in a close race, an Emory economist suggests that beyond pundits and pollsters, the curious may also consult a lesser-known crystal ball: election markets.

Through election markets, also called prediction markets, voters put their money where their mouths are by buying "shares" that reflect a candidate's chances of winning — essentially betting in an online futures market about the nation's election outcome.

Though rarely referenced by news programs or political analysts, election markets are actually a viable tool that can be used in conjunction with polls and statistical models to help predict election outcomes, says Monica Capra, an associate professor of economics at Emory with research interests in behavioral and experimental economics.

"Basically, the prediction markets are futures markets, exchanges in which people trade asset shares — candidates, in this case — based upon what they believe will happen in the future," says Capra, who teaches about the topic in her experimental economics classes. "The idea that presidential markets can predict election outcomes comes from the fact that markets are aggregators of individual beliefs," she adds. "It's a perfect application for elections — we know when the election will take place and who the candidates are. Trades are made on the belief of who will win."

Election trading typically takes place through online websites, such as Intrade.com, based in Ireland, Betfair.com in England, and the University of Iowa Electronic Markets, where spectators follow the fortunes of their candidates — or other real-world events — by tracking how they're "trading" in the eyes of the public, or bettors.

This week, for example, activity at Intrade.com showed the odds of President Barack Obama winning re-election improving throughout Tuesday night's debate, rising from 61.7 percent before the debate to 64.1 percent shortly afterward — a trend noted on the other sites, as well.

If it sounds like online gambling, that's because it is, acknowledges Capra, who doesn't play the market herself, nor require her students to play it. But as an economist, she does consult it: beneath the profit motive lies a fascinating glimpse into the mind of the American voter. And there can be value in listening to the betting public.

"The fact that there is money on the table gives people more inspiration to gather information and do some homework," Capra says. 

"Markets are information aggregators," she explains. "People arrive with different sets of information and beliefs that are revealed through their trading behavior and captured by the market. That idea is what makes predictive markets work. Basically, it's an economist's crystal ball."

The system works like this: Let's say you want to bet on the likelihood that Mitt Romney will win the 2012 presidential race. You buy "shares" — this week, they're running around $3.66 on Intrade. If he wins, all shares jump to $10 each and you make money. If he loses, all shares immediately plunge to $0 and you lose.

Predictive market sites also post a probability for each candidate winning. This week, for instance, Obama's shares were running about $6.32, which puts him at a 63.1 percent chance of winning. In contrast, Romney's shares were selling at $3.67 each, with a 36.9 percent chance of victory. That can change in an instant.

With websites updating trading around the clock, "it's a market that never closes," Capra observes. However, she offers an important caveat: predictive markets traders don't necessarily represent the average voter. While a political pollster may seek a representative sample of the population, predictive market traders in the Iowa Electronic Market, for instance, tend to be predominantly male, younger, wealthier and more educated than the average voter.

"But as long as you have people informed and motivated to trade in order to make money, that's all you need for the market to work well," she adds, suggesting that traders are more likely to make choices based on solid data rather than emotional impulse when money is at stake.

Capra says she consults predictive markets every day. "Right now, Gallup polls give the edge to Romney," she notes. "But InTrade says Obama will win — his predicted percentage rose both during and after this week's debate. The fact that he did much better in this debate was reflected by people immediately buying shares. The second debate also appeared to stop the upward movement of Romney shares."

So how accurate are online election markets? Though researchers are divided on the topic, Capra says she considers them a valid predictive tool: "As an economist, you have three main sources for predicting election outcomes: forecasting models, daily polls and prediction markets. If I had to choose one, I would choose prediction markets."

Monday, October 22, 2012

'Still crazy' for Paul Simon's pop psychology



Emory psychologist Marshall Duke, who is 70, came of age listening to the music of Paul Simon, who just turned 71. As a scientist who studies the importance of stories and rituals to the human experience, Duke is fascinated by what he calls Simon’s “theory of mind,” or his uncanny capacity to understand what it is to be someone else and to tell the stories of people across generations.

“The songs he writes are not necessarily contemporaneous with his own age,” Duke says. He cites “Old Friends,” written by Simon during his 20s, as just one example:

Old friends sat on their park bench like bookends / Winter companions / The old men lost in their overcoats / Waiting for the sunset / The sounds of the city sifting through trees settle like dust on the shoulders of the old friends / Can you imagine us, years from today, sharing a park bench quietly? / How terribly strange to be 70

“As I turned 70 a few weeks ago,” Duke says. “I realized how profound the words were, even though they were written by a young man.”

Duke describes Simon’s song “Slip Slidin’ Away” as “a verbal equivalent of the skull that is placed at the bottom of the crucifix paintings in the Renaissance, which says, ‘Be aware, life is temporary, life is fragile.’” A few of the lyrics:

We work our jobs / Collect our pay / Believe we’re gliding down the highway / When in fact we’re slip slidin’ away.

“Paul Simon understands that we’re all still crazy after all these years,” Duke says. “He understands that we don’t ever lose the childishness that belongs to us as a gift when we’re little. It’s something that allows us, even when we’re astounded that we’re 70, to hold onto some of the behaviors and fun of being seven.”

Paul Simon will deliver the 2013 Richard Ellmann Lectures in Modern Literature at Emory, February 10-12. The series of free public talks will include Simon's reflections on his early music. Click here for more information.

Related:
Margaret Atwood on aliens and angels
Stories your parents should have told you
The dawn of collective human unconsciousness

Tuesday, October 16, 2012

Sharing ideas about the concept of fairness

You've got just two pieces of Halloween candy left in the bowl. Who are you going to give them to?

By Carol Clark

Ask a three-year-old to divide pieces of a favorite candy between himself and two other children and he will likely question why he should share any at all. “At that age, children basically self-maximize. They have a guiltless selfishness,” says Emory psychologist Philippe Rochat, who studies the emergence of a moral sense in children.

By the age of five, children tend to be more principled in the way that they regard others. A five-year-old, for example, may go so far as to split the candies in half to ensure everyone gets an equal share.

“Something else interesting happens around the age of seven,” Rochat says. “The earlier tendency to self-maximize regains power as children start aligning themselves with groups. They generate inequity by favoring their own group when it comes to sharing.” 

Emory is inviting the public to an October 18-19 event, the "Fairness Conference: An Interdisciplinary Reflection on the Meanings of Fairness." An international group of scholars, from psychology, law, anthropology, ethics, philosophy, economics and politics will offer their views on the concept of fairness. Click here to see the full schedule and to register for the free event, to be held at the Silverbell Pavilion of the Emory Conference Center.

Fairness is the foundation of what makes us sociable and able to live together, but it can be hard to define.

“It is something that we often take for granted, as ingrained into our being,” Rochat says. “But ideas about what’s fair change through child development, across cultures and amid different political and economic circumstances. The conference aims to bring light and clarity to the subject from multiple scientific perspectives.”

Jerome Bruner, an educational psychologist from New York University, will give the keynote entitled “The Ambiguities of Fairness.” His presentation will cover how the violation of fairness was handled by the ancient Greeks, a group of islanders in remote Melanesia and in contemporary Sicily – the source of the proverb “Vengeance is a dish that must be served cold.”

In addition to Emory researchers, the speakers include scholars from the University of Pennsylvania, Harvard, Yale, Lebanese American University, and the Universidad Autonoma de Entre Rios, Argentina.

President Jimmy Carter will give a presentation at the conference entitled “Fairness and Equity in Politics and Human Affairs.”

The issue of fairness will grow increasingly important as the human population increases, Rochat says. Climate change, pollution, diminishing resources, global commerce and immigration are just a few of the issues that will put more pressure on the question of fairness.

“We want to give a scientific rooting to a problem that affects every part of society,” Rochat says. “Much of the tension in the current U.S. presidential election, for example, boils down to different views of what is fair. How much tax should the rich pay? How much support should the poor get?”

Related:
First blush: When babies get embarrassed

Images: iStockphoto.com.

Monday, October 15, 2012

Physicists crack another piece of the glass puzzle

The experiment showed how particles on the verge of becoming a glass move like cars trying to get out of a grid-locked parking lot.

By Carol Clark

When it comes to physics, glass lacks transparency. No one has been able to see what’s happening at the molecular level as a super-cooled liquid approaches the glass state – until now. Emory University physicists have made a movie of particle motion during this mysterious transition.

Their findings, showing how the rotation of the particles becomes decoupled from their movement through space, are being published in the Proceedings of the National Academy of the Sciences.

“Cooling a glass from a liquid into a highly viscous state fundamentally changes the nature of particle diffusion,” says Emory physicist Eric Weeks, whose lab conducted the research. “We have provided the first direct observation of how the particles move and tumble through space during this transition, a key piece to a major puzzle in condensed matter physics.”

Weeks specializes in “soft condensed materials,” substances that cannot be pinned down on the molecular level as a solid or liquid, including everyday substances such as toothpaste, peanut butter, shaving cream, plastic and glass.

Scientists fully understand the process of water turning to ice. As the temperature cools, the movement of the water molecules slows. At 32 F, the molecules lock into crystal lattices, solidifying into ice. In contrast, the molecules of glasses do not crystallize.The movement of the glass molecules slows as the temperature cools, but they never lock into crystal patterns. Instead, they jumble up and gradually become glassier, or more viscous. No one understands exactly why.

The phenomenon leaves physicists to ponder the molecular question of whether glass is a solid, or merely an extremely slow-moving liquid.

This purely technical physics question has stoked a popular misconception: That the glass in the windowpanes of some centuries-old buildings is thicker at the bottom because the glass flowed downward over time.

“The real reason the bottom is thicker is because they hadn’t yet learned how to make perfectly flat panes of glass,” Weeks says. “For practical purposes, glass is a solid and it will not flow, even over centuries. But there is a kernel of truth in this urban legend: Glasses are different than other solid materials."


Shattering myths: For all practical purposes, glass is a solid. But physicists are still struggling to explain how, and when, a liquid transitions into a glassy material.

To explore what makes glasses different, the Weeks lab uses mixtures of water and tiny plastic balls, each about the size of the nucleus of a cell. This model system acts like a glass when the particle concentration is increased.

A major drawback to this model system is that actual glass molecules are not spherical, but irregularly shaped.

“When the hot molten liquid that forms a glass cools down, it’s not just that the viscosity becomes enormous, growing by a factor of a billion, there is something different about how the molecules are moving,” Weeks says. “We wanted to set up an experiment that would allow us to see that movement, but spheres move differently than irregular shapes.”

In 2011, however, the physics lab of David Pine, at New York University, developed a way to join clusters of these tiny plastic balls together to form tetrahedrons.

Kazem Edmond, while a graduate student at Emory, added these tetrahedral particles to the glass model system and led the experiments. Using a confocal microscope, he digitally scanned the samples as the viscosity increased, creating up to 100 images per second.

The result was three-dimensional movies that showed the movement and the behavior of the tetrahedrons as the system reached a glassy state.



The movie and data from the experiment provide the first clear picture of the particle dynamics for glass formation. As the liquid grows slightly more viscous, both rotational and directional particle motion slows. The amount of rotation and the directional movements of the particles remain correlated.

“Normally, these two types of motion are highly coupled,” Weeks says. “This remains true until the system reaches a viscosity on the verge of being glass. Then the rotation and directional movements become decoupled: The rotation starts slowing down more.”

He uses a gridlocked parking lot as an analogy for how the particles are behaving. “You can’t turn your car around, because it’s not a sphere shape and you would bump into your neighbors. You have to wait until a car in front of you moves, and then you can drive a bit in that direction. This is directional movement, and if you can make a bunch of these, you may eventually be able to turn your car. But turning in a crowded parking lot is still much harder than moving in a straight line.”

Previous research has inferred this decoupling of movement by experimenting with actual molecular glasses. The Weeks lab used a simple model system to scale up glassy material so that you can actually watch the decoupling process happening.

“Glass is important in everyday life,” Weeks says. “The more we understand its fundamental nature, the more we may be able to improve it and use it in different ways. One reason that smart phones are getting smaller and better, for example, is that stronger and thinner glass is being developed.”

Related:
Crystal-liquid interface made visible for the first time
A microcosm of awesome

Images: iStockphoto.com.