3 ms·

Scientists identify a mathematical 'crystal ball' that may predict calamities

31 points by fraqed 13y ago

Shorel 13y ago
Does anyone else remember "the green button" ?
forkandwait 13y ago
http://prl.aps.org/abstract/PRL/v111/i17/e177203 http://prl.aps.org/abstract/PRL/v111/i17/e177203
- deleted 13y ago
  [deleted]
ultramundane828 13y ago
As one person comments below the article, this totally is reminiscent of the Foundation trilogy.
annnnd 13y ago
I would argue that it is not prediction that is failing with economic systems; it is the lack of interest to change anything (from those who could) that triggers the consequences. After all, rich didn't get any poorer with the last crisis.
srl 13y ago
The paper: http://lizier.me/joseph/publications/2013-Barnett-InfoFlowIsingModel.pdf http://lizier.me/joseph/publications/2013-Barnett-InfoFlowIs...
- kens 13y ago
  Let me try to summarize the paper, which I only slightly understand. They take a 2-D grid with a magnetic domain at each point, sort of like a hard drive. It starts out with random N/S orientations. Each domain "wants" to match up with its neighbors. As domains flip, they will start to match up more and more. Eventually you have a phase transition where you suddenly go from mostly-random to mostly-aligned, kind of like water freezing. This is a standard physics model called an Ising model. They look at the "information flow" between neighboring domains. This is sort of how much influence a domain has on its neighbors, with an incomprehensible transfer entropy measure. At the beginning, when everything is random, there's not much correlation. At the end, when everything is aligned, there's no information flow since neighbors are already aligned. The peak influence is right in the middle when domains are snapping into alignment with each other. The paper measures this information flow via simulations of the grid and finds the peak information flow is in the disordered phase shortly before the phase transition to order. This seems like a reasonable conclusion. They then conjecture that this information flow peak isn't just for the specific Ising model they investigate but may happen in general for financial crises, epileptic seizures, and other complex models, so if you can measure information flow you can tell when the phase transition will happen. I don't see anything in the paper that actually supports the conjecture, but it makes for nice headlines. (I don't want to get into credentialism, but it makes me a bit suspicious that the authors aren't statistical physicists (who usually do Ising model stuff), but work in a center for consciousness science, civil engineering, and other random departments.) Apologies to anyone who actually understands Ising models, because I've probably totally mangled the explanation, but I figured since nobody else had posted a summary it might be useful.
- ChuckMcM 13y ago
  Thanks for that. I'm not convinced, it look like they try to correlate energy and lattice structure and then extrapolate from there to dynamic system collapse. Scanning it, I felt like it read like one of those 'autogenerated' papers, which is always a red flag for me.
  - FkZ 13y ago
    It seems unlikely this would be generalizable in much of a useful way. "We conjecture that this phenomenon is universal for a class of complex dynamical systems and discuss implications." the paper says, I'd like to see more on why they think it's reasonable to conjecture that.
EGreg 13y ago
This is going to sound funny, but HOW did they get the bottom bar to (unwittingly?) bring up the mobile Safari chrome around the website when tapped? Try it on an iphone... it's an incredibly nice effect
51Cards 13y ago
On reading the title my mind immediately went to the Nic Cage movie "Knowing". Someone needs to check if their process has a finite limit.
colanderman 13y ago
Hm… global information is flowing very quickly these days… what with the Internet and all. Are we on the edge of a "calamity"?
galapago 13y ago
"He who foresees calamities, suffers them twice over"
pertinhower 13y ago
From what I understand of chaos theory, and from what I'm hearing of recent trends in scientific overreaching and poor peer reviewing, I am inclined to dismiss this paper as yet another overambitious claim to know what can't be known. Divination is the world's oldest and most alluring scam. What makes this different?
jimmytidey 13y ago
If you have a method to predict epileptic seizures you can intervene. If you have a (published) method to predict stock market crises then the agents in the stock market will take it into account, presumably breaking the method.

31 points by fraqed 13y ago

Shorel 13y ago

Does anyone else remember "the green button" ?

forkandwait 13y ago

http://prl.aps.org/abstract/PRL/v111/i17/e177203 http://prl.aps.org/abstract/PRL/v111/i17/e177203

deleted 13y ago
[deleted]

ultramundane828 13y ago

As one person comments below the article, this totally is reminiscent of the Foundation trilogy.

annnnd 13y ago

I would argue that it is not prediction that is failing with economic systems; it is the lack of interest to change anything (from those who could) that triggers the consequences. After all, rich didn't get any poorer with the last crisis.

srl 13y ago

The paper: http://lizier.me/joseph/publications/2013-Barnett-InfoFlowIsingModel.pdf http://lizier.me/joseph/publications/2013-Barnett-InfoFlowIs...

kens 13y ago
Let me try to summarize the paper, which I only slightly understand. They take a 2-D grid with a magnetic domain at each point, sort of like a hard drive. It starts out with random N/S orientations. Each domain "wants" to match up with its neighbors. As domains flip, they will start to match up more and more. Eventually you have a phase transition where you suddenly go from mostly-random to mostly-aligned, kind of like water freezing. This is a standard physics model called an Ising model. They look at the "information flow" between neighboring domains. This is sort of how much influence a domain has on its neighbors, with an incomprehensible transfer entropy measure. At the beginning, when everything is random, there's not much correlation. At the end, when everything is aligned, there's no information flow since neighbors are already aligned. The peak influence is right in the middle when domains are snapping into alignment with each other. The paper measures this information flow via simulations of the grid and finds the peak information flow is in the disordered phase shortly before the phase transition to order. This seems like a reasonable conclusion. They then conjecture that this information flow peak isn't just for the specific Ising model they investigate but may happen in general for financial crises, epileptic seizures, and other complex models, so if you can measure information flow you can tell when the phase transition will happen. I don't see anything in the paper that actually supports the conjecture, but it makes for nice headlines. (I don't want to get into credentialism, but it makes me a bit suspicious that the authors aren't statistical physicists (who usually do Ising model stuff), but work in a center for consciousness science, civil engineering, and other random departments.) Apologies to anyone who actually understands Ising models, because I've probably totally mangled the explanation, but I figured since nobody else had posted a summary it might be useful.
ChuckMcM 13y ago
Thanks for that. I'm not convinced, it look like they try to correlate energy and lattice structure and then extrapolate from there to dynamic system collapse. Scanning it, I felt like it read like one of those 'autogenerated' papers, which is always a red flag for me.
- FkZ 13y ago
  It seems unlikely this would be generalizable in much of a useful way. "We conjecture that this phenomenon is universal for a class of complex dynamical systems and discuss implications." the paper says, I'd like to see more on why they think it's reasonable to conjecture that.

EGreg 13y ago

This is going to sound funny, but HOW did they get the bottom bar to (unwittingly?) bring up the mobile Safari chrome around the website when tapped? Try it on an iphone... it's an incredibly nice effect

51Cards 13y ago

On reading the title my mind immediately went to the Nic Cage movie "Knowing". Someone needs to check if their process has a finite limit.

colanderman 13y ago

Hm… global information is flowing very quickly these days… what with the Internet and all. Are we on the edge of a "calamity"?

galapago 13y ago

"He who foresees calamities, suffers them twice over"

pertinhower 13y ago

From what I understand of chaos theory, and from what I'm hearing of recent trends in scientific overreaching and poor peer reviewing, I am inclined to dismiss this paper as yet another overambitious claim to know what can't be known. Divination is the world's oldest and most alluring scam. What makes this different?

jimmytidey 13y ago

If you have a method to predict epileptic seizures you can intervene. If you have a (published) method to predict stock market crises then the agents in the stock market will take it into account, presumably breaking the method.