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Selected Media Coverage: January 18, 2007

Maths solution tops science class
12/21/2006 - BBC (cir. )

America Between the Turks and Kurds
12/13/2006 - Economist - New York Bureau, The (cir. 504,590)

BANGLADESH: President postpones elections
01/18/2007 - Radio Australia (cir. )

Economics: That's life
01/18/2007 - Washington Times (cir. 100,603)

What education-leadership professors are reading
01/17/2007 - Chronicle of Higher Education, The (cir. 100,000)


Maths solution tops science class
12/21/2006 - BBC (cir. )഍਀ഀ਀
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A solution to one of the most difficult problems in mathematics was the most important advance of 2006, according to the prestigious journal Science.

Grigory Perelman's proof of the century-old Poincare Conjecture has caused a sensation, and not just because of the brilliance of the work.

In August, the Russian became the first person to turn down a Fields Medal, the highest honour in mathematics.

He also seems likely to turn down a $1m prize offered by a US maths institute.

Dr Perelman is said to despise self-promotion and describes himself as isolated from the rest of the mathematical community.

But his work has set the field alight with excitement - and controversy.

Terence Tao, professor of mathematics at the University of California, Los Angeles, called Perelman's result "the best piece of mathematics we have seen in the last 10 years".

Timofey Shilkin, a former colleague of Perelman at the Steklov Mathematics Institute in St Petersburg, Russia, told BBC News: "He definitely deserves the Fields Medal - that is my personal opinion. I am completely sure he is a genius."

'Excellent mathematician'
He added: "I'm afraid he is quite a self-enclosed person. We know about him approximately the same as you know - not too much.

"I met him when he was a member of our group and our contacts were about once a week, but we had only short discussions.

"I know nothing about his personal life; I know only that he is an excellent mathematician."

The reclusive Dr Perelman left the Steklov Institute in January, and was last said to be unemployed and living with his mother in her apartment in St Petersburg.

For several years he worked, for the most part, alone on the Poincare Conjecture. Then, in 2002, he posted on the internet the first of three papers outlining a proof of the problem.

The Poincare is a central question in topology, the study of the geometrical properties of objects that do not change when they are stretched, distorted or shrunk.

The surface of the Earth is what topology describes as a two-dimensional sphere. If one were to encircle it with a lasso of string, it could be pulled tight to a point.

On the surface of a doughnut, however, a lasso passing through the hole in the centre cannot be shrunk to a point without cutting through the surface.

Checking the work
Since the 19th Century, mathematicians have known that the sphere is the only enclosed two-dimensional space with this property; but they were uncertain about objects with more dimensions.

The Poincare Conjecture says that a three-dimensional sphere is the only enclosed three-dimensional space with no holes.

Proof of the Conjecture eluded mathematicians until Perelman posted his work on the website arXiv.org.

This is a so-called pre-print server, where researchers upload study papers for informal feedback before they submit them to a peer-reviewed journal.

Feuding within the mathematical community now threatens to overshadow Dr Perelman's achievement.

The Russian had detailed a way to kick down the roadblock that had stymied a solution to the problem. It was then up to others to check his proof.

It was at this stage of the process - when mathematicians pored over Perelman's work to assess its accuracy - that much bad feeling started to rise to the surface.

'Complete proof'
In 2005, a Chinese team consisting of Huai-Dong Cao of Lehigh University and Xi-Ping Zhu of Zhongshan University published what they claimed was "the first written account of a complete proof of the Poincare Conjecture".

Cao and Zhu took on the task of checking Perelman's proof at the behest of their mentor Shing-Tung Yau, a Chinese-born professor of mathematics at Harvard University, US.

Shortly after the Cao-Zhu paper was published, Professor Yau gave a speech in which he was reported as having said: "In Perelman's work, many key ideas of proofs are sketched or outlined, but complete details of the proofs are often missing."

This drew the ire of others in the field, who said that Yau's promotion of his proteges' work went too far.

In a rare interview, Perelman told the New Yorker magazine: "It is not clear to me what new contribution did they make."

However, speaking to the New York Times newspaper in October, Professor Yau denied having said there were gaps in Dr Perelman's work.

Science magazine also named its "breakdown" of the year: the scandal involving South Korean cloning pioneer Hwang Woo-suk, whose report of the production of stem cells from a cloned human embryo was found to have been faked.

Science magazine's breakthroughs of 2006

1. The Poincare Conjecture. Reclusive Russian mathematician Grigory Perelman apparently solved the venerable mathematical problem.

2. Digging out fossil DNA. Researchers used new techniques to sequence more than one million bases of nuclear DNA from a Neanderthal.

3. Shrinking Ice. Glaciologists discovered that the world's two great ice sheets were indeed losing water to the oceans - at an accelerating pace.

4. From sea to land. Details emerged of a 375-million-year-old fish that fills an evolutionary gap between sea creatures and land animals.

5. The Ultimate Camouflage. A British-American team built a "metamaterials" cloaking device, that rendered an object invisible to microwaves.

6. Ray of Hope. Clinical trials show the drug ranizumab improved the vision of about one-third of patients with an age-related condition that causes degeneration in vision.

7. The road to speciation. Studies on the fruit fly and on butterflies aided our understanding of how species arise.

8. Beyond the light barrier. New microscopy techniques allowed biologists to get a clearer view of the fine structure of cells and proteins.

9. The Persistence of Memory. Neuroscientists provided insights into how the brain records new memories.

10. Small molecules. Researchers reported a new class of small RNA molecules that shut down gene expression.


America Between the Turks and Kurds
12/13/2006 - Economist - New York Bureau, The (cir. 504,590)

Commentary
Economics: That”s life
By Alfred Tella

Take a look at some of the papers delivered at the annual meeting of the American Economics Association (AEA) held in Chicago earlier this month in conjunction with other social science groups.

Of the hundreds of research papers presented, many were of the usual war-horse variety, albeit on important topics, such as income, employment, productivity, output, inflation, international trade and immigration. Yet others reported on research that illuminated less traditional contemporary issues. A few attention-grabbers summarized.

(1) A paper by Alan B. Krueger of Princeton University and the National Bureau of Economic Research (NBER), “The National Origins of Foreign Fighters in Iraq,” analyzed the factors associated with foreigners joining the terrorists and insurgents in the Iraq war. The study used U.S. military data on foreign nationals from 27 countries who were captured in Iraq in 2005. Mr. Krueger”s model estimated the relative importance of origin countries” population size, distance, output per capita, percent of the population that is Muslim, U.S. foreign aid received, infant mortality (as an indicator of living conditions), level of civil liberties, literacy rate, whether the country was a member of the multinational coalition in Iraq, and the number of U.S. military troops stationed in the country.

The main findings of the study were “that countries with a large Muslim population, close proximity to Baghdad, low level of civil liberties or political rights, and low infant mortality rates are likely to have more of their citizens join the Iraqi insurgency. A country”s literacy rate, GDP per capita, and membership in the multinational coalition were unrelated to the number of foreign fighters in Iraq.” U.S. foreign aid was also found to have an insignificant effect. Mr. Krueger”s model accurately predicted the number of captured insurgents from most foreign countries.

(2) Another arresting title was “Fast-Food Restaurant Advertising on Television and Its Influence on Childhood Obesity,” by Shin-Yi Chou of Lehigh University and the NBER, Inas Rashad of Georgia State University, and Michael Grossman of the City University of New York and the NBER. The authors noted the upward trend in the percent of overweight children in the U.S. and their increased exposure to fast-food advertising on TV, adding that “the Bush administration has argued that no one has proven that advertising causes obesity and did not take action in regulating advertising directed at children, after the World Health Organization proposed that countries be urged to limit advertisements that encourage unhealthy diets, especially those directed at children.”

The study drew on national longitudinal survey data that followed children over time and data on fast-food advertising from Competitive Media Reporting, a large tracking service. The authors” model zeros in on the impact of fast-food effects, controlling for other factors that influence caloric consumption. They found that a ban on TV fast-food advertising “would reduce the number of overweight children... by 18 percent and would reduce the number of overweight adolescents... by 14 percent.” Males would benefit most. “The elimination of tax deductibility of this type of advertising would produce smaller declines of between 5 and 7 percent.”

(3) Another interesting paper was the “Sensitivity of the U.S. Economy to Weather Variability,” by Megan Harrod and Donald Waldman of the University of Colorado, Peter H. Larsen of the University of Alaska and Jeffrey K. Lazo of the National Center for Atmospheric Research. Using historical weather observations, the authors developed a model to estimate the sensitivity of different sectors of the economy and individual state economies to changes in temperature and precipitation.

The results showed that the service, trade and communications sectors were only slightly affected by changes in weather, whereas agriculture and mining were strongly impacted. The states whose economic output was most sensitive to weather variability were New York, Ohio, Alabama, Wyoming and California, though all states were affected to varying degrees. Nationally, annual output was estimated to vary by more than 3 percent due to changes in the weather.

(4) Did you ever wonder whether auction winners on eBay are overpaying because of shill bidding Joseph Engelberg and Jared Williams of Northwestern University examined this question in their paper, “EBay”s Proxy Bidding A License to Shill.” EBay does a multibillion-dollar auction business annually, bigger than the economies of many countries. When auction bids are placed by a seller or a seller”s accomplice to raise the price, that”s called shilling, a fraud in violation of eBay”s user agreement. The authors found evidence that it occurs and that it increases eBay profits.

The paper explained the strategy that enables shill bidders to raise auction prices without winning the auction and further demonstrated how eBay could reduce shill bidding, though that would hurt its profits.

The full text of these and other illuminating studies can be found on the AEA”s web site. While you”re there, another intriguing paper you might want to look at is “How to Organize Crime.” Alfred Tella is former Georgetown University research professor of economics. Copyright © 2007 News World Communications, Inc. All rights reserved.


What education-leadership professors are reading
01/17/2007 - Chronicle of Higher Education, The (cir. 100,000)


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A glance at the current issue of Educational Administration Quarterly: What education-leadership professors are reading

Three researchers have surveyed professors of educational leadership to determine which journals they read most and which they rank highest in terms of quality.

The researchers -- Perry A. Zirkel, a professor of education and law at Lehigh University; C. Russell Mayo, a deputy school superintendent in Pennsylvania; and Brian A. Finger, an elementary-school principal in Pennsylvania -- surveyed 240 professors at member institutions of the University Council for Educational Administration, a consortium of doctoral programs in education policy. Participants drew from a list of 34 popular educational-leadership periodicals to rank those they believed to be the top five in terms of quality. The researchers also asked the professors to name which periodicals from that same list they read most often.

The leading five publications, determined by the percentage of respondents who gave them a top ranking, were Educational Administration Quarterly, the American Educational Research Journal, Educational Leadership, Phi Delta Kappan, and Educational Evaluation and Policy Analysis. Professors said they most regularly read Educational Leadership.

The researchers say that professors of educational leadership belong to a community that stresses scholarly activity. At the same time, they note, such professors serve leaders "who value applications of knowledge to problems of practice and policy." The authors conclude that "the professional periodicals that professors rank highest in terms of quality and greatest usage reflect this balancing act of interests."

The article, "Research Notes From the Field: Which Journals Are Educational Leadership Professors Choosing," is available to subscribers or for purchase through Sage Publications.

Posted on Thursday, January 18, 2007

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