Possible Early Warning Sign for Market Crashes
by ilene - March 20th, 2011 6:45 pm
Complexity researchers who study the behavior of stock markets may have identified a signal that precedes crashes.
They say the telltale sign is a measure of co-movement, or the likelihood of stocks to move in the same direction. When a market is healthy, co-movement is low. But in the months and years before a crash, co-movement seems to grow.
Regardless of whether stock prices go up or down or stay the same, they do so in tandem. People are copying each other, and a small nudge can send everyone in the same direction. The system appears primed for collapse.
“One of the most important things happening now is that economists are trying to understand, what is systemic risk? When is the entire system vulnerable to disaster? Our results show that we have a direct, unambiguous measure of that vulnerability,” said Yaneer Bar-Yam, president of the New England Complex Systems Institute.
Seen through an econophysicist’s eyes, a stock market panic is an avalanche.
Bar-Yam’s findings, released Feb. 13 on arXiv, are part of an emerging research field known as econophysics. It applies to economics insights from the physical world, especially from systems in which networks of interacting units produce radical collective behaviors.
Heated water turning to gas is one such behavior, known technically as a phase transition. Another is snow gathering into an avalanche. Seen through an econophysicist’s eyes, a stock market panic is an avalanche, too.
Keep reading here: Possible Early Warning Sign for Market Crashes | Wired Science | Wired.com.
 Twitter
|
LinkedIn
|
 del.icio.us
|
|
Why God Did Not Create the Universe
by ilene - September 10th, 2010 2:07 pm
Interesting top 10 most popular article in Wall Street Journal. – Ilene
Why God Did Not Create the Universe
There is a sound scientific explanation for the making of our world—no gods required
By STEPHEN HAWKING And LEONARD MLODINOW, WSJ
Many improbable occurrences conspired to create Earth’s human-friendly design, and they would indeed be puzzling if ours were the only solar system in the universe. But today we know of hundreds of other solar systems, and few doubt that there exist countless more among the billions of stars in our galaxy. Planets of all sorts exist, and obviously, when the beings on a planet that supports life examine the world around them, they are bound to find that their environment satisfies the conditions they require to exist.
[...]
Many people would like us to use these coincidences as evidence of the work of God. The idea that the universe was designed to accommodate mankind appears in theologies and mythologies dating from thousands of years ago. In Western culture the Old Testament contains the idea of providential design, but the traditional Christian viewpoint was also greatly influenced by Aristotle, who believed "in an intelligent natural world that functions according to some deliberate design."
That is not the answer of modern science. As recent advances in cosmology suggest, the laws of gravity and quantum theory allow universes to appear spontaneously from nothing. Spontaneous creation is the reason there is something rather than nothing, why the universe exists, why we exist. It is not necessary to invoke God to light the blue touch paper and set the universe going.
Our universe seems to be one of many, each with different laws. That multiverse idea is not a notion invented to account for the miracle of fine tuning. It is a consequence predicted by many theories in modern cosmology. If it is true it reduces the strong anthropic principle to the weak one, putting the fine tunings of physical law on the same footing as the environmental factors, for it means that our cosmic habitat—now the entire observable universe—is just one of many.
|
Twitter
|
LinkedIn
|
del.icio.us
|
|
Laplace’s Hammer: The End of Economics
by ilene - May 31st, 2010 5:24 am
Laplace’s Hammer: The End of Economics
Courtesy of Tim at The Psy-Fi Blog
Clever Man, Stupid Idea
Simon-Pierre Laplace was a Very Clever Man who did many Very Clever Things. Unfortunately, like many clever men, having got hold of a Brilliant Idea he was rather inclined to go off and use it on everything in sight, which led to a number of Very Odd Conclusions. In fact as far as science goes, he may well have been the original man with a hammer; taking aim at every problem as though it was a nail.
As is the way of these things economists got hold of Laplace’s ideas, converted them to their own and started developing delicate and intricate webs of theories and practices. Unfortunately, over the succeeding three hundred years they’ve failed to keep up with advances in physics and biology, rather leaving economists as the only believers in an approach that suggests we have no free will, a position from which they’re having to be dug out and defused, one unexploded theorist at a time.
Newton’s Error
When Isaac Newton published his theory of gravity he knew it contained a serious flaw; his equations didn’t exactly match what was observed. He reckoned, correctly, that the differences between his theory and the observations were down to the gravitational effect on the planets of other planets – so called perturbations, which he didn’t know how to mathematically model. He said:
“But to consider simultaneously all these causes of motion and to define these motions by exact laws admitting of easy calculation exceeds, if I am not mistaken, the force of any human mind.”
And, of course, he was mistaken. The force of Laplace’s mind successfully solved the problem. Having achieved this, though, Laplace went a stage further. Because he could exactly calculate the position of any planet he could compare this with the results of observations from astronomers. What he discovered changed human history.
Observer Bias
It turned out that observers made errors, but they made them in a particular way – their observations fell about the actual position of the planet in a very distinctive pattern. This pattern, of course, was the ultra-familiar Bell curve or normal distribution. Laplace realised that human error was statistically quantifiable and, therefore, could be effectively eliminated from the data. This…
|
Twitter
|
LinkedIn
|
del.icio.us
|
|
German
Spanish
French
Italian
Portuguese
Japanese
Korean
Russian
Chinese
Philip R. Davis is a founder Phil's Stock World, a stock and options trading site that teaches the art of options trading to newcomers and devises advanced strategies for expert traders...
Ilene is editor and affiliate program
coordinator for PSW.
