Thursday, November 29, 2007

PISA results 2006 (Science)


OECD has just released the tables for the 2006 PISA survey on science skills of the 15-year old. (See the table on the left). I am also attaching below an extract of the relevant OECD news release.
Although some people critisize this kind of ranking, I consider this exercise an important tool in the effort to improve an educational system.

The PISA survey, based on tests carried out in 2006 in 57 countries that together account for nearly 90% of world GDP, is the most comprehensive and rigorous international yardstick of secondary-school students' attainments. After focusing in 2000 on reading skills and in 2003 on mathematics, PISA 2006 tested students on how much they knew about science and their ability to use scientific knowledge and understanding to identify and address questions and resolve problems in daily life.
Comparisons between the results of the 2006 tests and those of previous years are not strictly valid.

PISA is a three-yearly survey of the knowledge and skills of 15-year-olds in OECD member countries and partner countries and economies. The product of collaboration between participating countries through the Organisation for Economic Co-operation and Development (OECD), it draws on leading international expertise to develop valid comparisons across countries and cultures.
In 2006,
PISA assessed the competencies of 15-year-old students in 57 countries with an extensive two-hour test. More than 400,000 students from 57 countries making up close to 90% of the world economy took part. The focus was on science but the assessment also included reading and mathematics and collected data on student, family and institutional factors that can help to explain differences in performance.
The table summarises the performance of 15-year-olds in science.
It shows three main pieces of information:
The average score of the country on the science assessment. Across the 30 OECD countries the scores are statistically standardised to have an average of 500 points. The scores are also standardised so that approximately two-thirds of the students score between 400 and 600 - that is the standard deviation is 100. The colour coding in the list of the countries in the first column gives an indication of whether the country's score is statistically significantly above, below or not different from the OECD average.

  • The rank of the country compared to other OECD countries. When a sample of students represents all students in a country, it is not always possible to state with 100% accuracy what the exact rank of the country is compared with other countries. For this reason, OECD calculates, with 95% confidence, a range of ranks that the country falls within. For example, in the list above, OECD is 95% confident that New Zealand ranks between 2nd and 5th of all the OECD countries.
  • The rank of the country compared to all the countries which participated in PISA 2006. The same 95% level of confidence is applied when comparing a country's position to all the other countries. For example, the list above shows, with 95% confidence, that Croatia ranks between 23rd and 30th position of all the countries which participated in PISA 2006.
  • For further background reading, see :
Assessing Scientific, Reading and Mathematical Literacy, A Framework for PISA 2006,
Sample test questions from the PISA 2006 assessment







Wednesday, November 28, 2007

Gandhi's ten principles of nonviolence

I found them in the home page of Dean Foster (There many more interesting things in it).


  1. Humiliating or deliberately provoking your opponent invites violence;
  2. Knowing your facts and arguments well helps avoid violence;
  3. If you are open about your cause your opponent is less likely to be violent;
  4. Look for common ground between you and your opponents to promote trust and understanding;
  5. Do not judge others harder than yourself (alternatively do not judge others);
  6. Try to trust your opponent. They will sense this trust;
  7. Compromise on inessential items to promote resolution;
  8. Sincerity helps convert your opponent;
  9. By making personal sacrifice you show your sincerity;
  10. Avoid exploiting weakness in your opponent. Aim for integrity, not simply to win.

Saturday, November 24, 2007

The Australian Election

I just realised that the labour party is -at last!- winning an election in Australia and that John Howard is loosing his seat!
This sounds like good news for Australia!

Friday, November 23, 2007

Commonwealth, Musharraf and Bush

The suspension of Pakistan from the councils of the Commonwealth and statement of G.W. Bush that all is fine in Pakistan raises a question: Are tha facts different or they are interpreted differently?

Thursday, November 22, 2007

The Israel Lobby in the US

There is a lot of controversy about the book The Israel Lobby and U.S. Foreign Policy, by John J. Mearsheimer and Stephen M. Walt .
In Amazon.com the book rating (at the moment this is posted) is 4 stars. Interestingly, this average is the result of plenty 5- star and a few 1-star reviews.
A rebuttal entitled "The Deadliest Lies: The Israel Lobby and The Myth of Jewish Control" was written by Abraham H. Foxman. Here, the Amazon average rating is 2 stars (so far), in this case consisting of plenty 1-star and a few 5-star reviews.
An interesting (and lengthy) comment by Henri Astier can be found on the BBC web site.

Tuesday, November 20, 2007

Migraine brains 'are different'

Those who have experienced this problem know how important this development is.

Scientists have discovered differences in the sensory areas of the brains of people who develop migraines.They found a part of the cortex is thicker than in people who are free from the debilitating headaches. What is not clear is whether the difference causes, or is the result of migraine attacks. The Neurology study, by Massachusetts General Hospital in Boston, suggests the changes may make patients hyper-sensitive to pain in general. The researchers, from the hospital's Martinos Center for Biomedical Imaging, compared 24 people who get migraines with 12 who do not suffer the condition. They found the somatosensory cortex area of the brain was up to 21% thicker in the migraine sufferers.
The full story from the BBC.

Monday, November 19, 2007

Amazon's digital book reader

From the BBC: Online retailer Amazon has unveiled an own-brand wireless electronic book reader called Kindle. The paperback-sized device is on sale immediately in the US for $399 (£195). It can store up to 200 books in its onboard memory.Kindle does not need a PC to be loaded with books, blogs or papers - instead content arrives via wireless.Amazon said 90,000 books, including bestsellers priced at $9.99, were available for Kindle at launch.

Sunday, November 18, 2007

An inconvenient truth about eating meat

A very interesting article in the NYT with the same title refers to the argument by the animal rights groups that raising animals for meat contributes more to global warming than all the sport utility vehicles combined. It is well documented and emphasizes the fact that Al Gore hardly makes reference to the issue.

Saturday, November 17, 2007

Robots and Biological communities

Mini-robots designed at EPFL managed to integrate themselves into a community of cockroaches, interacting with them and influencing their collective decision-making behavior. (The relevant article appeared in science magazine).
I consider this development as one of the most important advances of science with far-reaching implications.

Tuesday, November 13, 2007

The Israel Factor: Ranking the US Presidential Candidates

I wish I could see a similar ranking in a Greek newspaper with reference to Greece's interests. (The ranking in Haaretz is updated every month!).

Man marries bitch to beat curse

A bbc story:
An Indian man has married a female dog, believing the union will help him atone for stoning two other dogs to death. Selvakumar, 33, said he had been cursed since the killings, suffering paralysis and a loss of hearing.The wedding took place at a Hindu temple in Tamil Nadu state. The "bride" wore an orange sari with a flower garland and was fed a bun to celebrate.Superstitious people in rural India sometimes organise weddings to animals in the hope of warding off curses.

Friday, November 02, 2007

Hillary and Bill Clinton in California

From a Field Poll taken Oct. 11-21 of 579 registered state voters.
Overall, 70 percent of California voters surveyed have made up their minds about how they would vote if Clinton emerged as the Democratic presidential nominee - 36 percent would definitely support her and 34 percent definitely would not.
Mark DiCamillo, director of the Field Poll, said the survey showed "there's really been a solidification of voter opinions on Hillary" and what he called "a negative drag" unique in the presidential race - the solid third who don't like her, won't support her and see her negatively.
"Judging from the length of time we've seen the same proportions, I don't think there's a high probability they will change their minds," he said.
That means Clinton, in order to carry the state, has "a more limited playing field than other candidates would have ... she almost has to write off at least a third of the voters who are unlikely to vote for her," DiCamillo said. "No other candidates have this kind of solidification of negative votes."
But there are positives for Clinton, too, in the current polling - including the way her husband influences the campaign. The former president is more favorably viewed than his wife in California - with a 56 percent to 37 percent favorable-unfavorable rating. More than two-thirds of state voters across the political spectrum believe he will be an asset to her campaign and her presidency if she is elected in 2008.
The full article.

Thursday, November 01, 2007

Teach For America

From an e-mail I received. An impressive -and effective- initiative.

In her senior thesis as an undergraduate student at Princeton University, Wendy Kopp outlined a plan to recruit outstanding recent college graduates to teach for two years in America's neediest urban and rural schools. Upon graduation, she founded Teach For America, a national corps that would
have an important impact on the nation's education system, putting a dent in the lingering problem of educational inequity. She has spent the past 18 years developing the corps into a prestigious, highly regarded program that attracts some of the nation's brightest young men and women.
Today, 5,000 corps members reach approximately 440,000 students in low-income communities across the country. They join more than 12,000 Teach For America alumni who are assuming significant leadership roles in education and social reform. These alumni are running some of the most acclaimed schools in low-income areas, advising governors and senators on education policy, and marshalling the resources of companies and law firms toward education reform.