users online counter
Interesting

Destroying drug cartels, the mathematical way. By Sara Reardon




Killing drug lords gets headlines, but complexity analysis suggests they are the wrong people to target to bring down a cartel
WHEN the Mexican navy announced on 9 October that Heriberto Lazcano, leader of the country’s most violent criminal cartel, Los Zetas, had been killed it was hailed as a major victory in the war on drugs. But it’s doubtful that Lazcano’s death will be the end of Los Zetas - or reduce violence in Mexico. After all, there is already a new leader.
More useful targets might be those apparently minor players with key connections, according to a complexity analysis approach that could help Colombia - the world’s largest producer of cocaine - investigate and prosecute cartel members.
Complexity analysis depicts drugs cartels as a complex network with each member as a node and their interactions as lines between them. Algorithms compute the strength and importance of the connections. At first glance, taking out a central “hub” seems like a good idea. When Colombian drug lord Pablo Escobar was killed in 1993, for example, the Medellin cartel he was in charge of fell apart. But like a hydra, chopping off the head only caused the cartel to splinter into smaller networks. By 1996, 300 “baby cartels” had sprung up in Colombia, says Michael Lawrence of the Waterloo Institute for Complexity and Innovation in Canada, and they are still powerful today. Mexican officials are currently copying the top-down approach, says Lawrence, but he doubts it will work. “Network theory tells us how tenuous the current policy is,” he says.
Now Colombian prosecutors have a new tool to add to their investigation methods: network analysis. This can be an integral part of the modern war on drugs, says Eduardo Salcedo-Albaran, director of the Vortex Foundation based in Bogotá.
Vortex uses network-analysis algorithms to construct diagrams for court cases that show the interactions between cartel members, governors and law enforcers. These reveal links that are not otherwise visible, what Salcedo-Albaran calls “betweeners” - people who are not well-connected, but serve as a bridge linking two groups. In Mexico and Colombia, these are often police or governors who are paid by the cartels.
“The betweener is the guy who connects the illegal with the legal,” says Salcedo-Albaran. Because many cartels depend on their close ties with the law to operate successfully, removing the betweeners could devastate their operations.
It’s a reasonable strategy, says Michael Kenney of the University of Pittsburgh in Pennsylvania, although it shouldn’t be the only one governments use. The ideal strategy depends on government goals. If it is the end of the drug trade they are after, removing the leaders may work. But if the goal is to reduce violence, as incoming Mexican president Enrique Peña Nieto has vowed to do, targeting kingpins like Lazcano will have the opposite effect, says Vanda Felbab-Brown of the Brookings Institution in Washington DC. Smaller organisations that emerge from a broken cartel tend to assert their power by torturing and killing people.
Fighting all these factions would require even more firepower. Sean Gourley, of the data analysis organisation Quid in San Francisco, used public data from nine recent insurgencies, including Colombia’s drug war, to determine mathematically how these battles play out (Nature, doi.org/bv2tf5). “Unfortunately, if you put more forces on the ground, you elongate the violence,” he says.
Data collected by the Transborder Institute in San Diego, California, supports this. Prior to the crackdowns that began in 2006, drug-related crimes in Mexico killed about 3700 people per year. In 2011, that number was more than 16,000.
“People keep saying that the violence [in Mexico] will get worse before it gets better, and the cartels are at the end of their lives, but those predictions have been going on for years,” says Lawrence. At some point, he suggests, a more mathematical approach will win out.

Lost your cartel? Just Google it
Mexican cartels aren’t subtle about their whereabouts. To intimidate their rivals and the government, they advertise their latest crimes through the media and threaten each other on blogs and websites.
But this practice has been revealing their inner workings to Viridiana Rios and Michele Coscia of Harvard University. In a paper that will be presented at the CIKM conference in Hawaii this month, the two created a program called MOGO that searches Google News for references to the different cartels, their locations and their influence between 1999 and 2011.
They used MOGO to construct a map showing where all the cartels were working at each point in time. Their map turned out to be quite accurate, correlating closely with those developed by the global intelligence firmStratfor.
The cartels’ movements reveal a lot about their business strategies, says Rios. Some, such as Los Zetas, are very aggressive, expanding quickly into new territories and competing with rivals. Older organisations such as Sinaloa prefer to strengthen their own territories rather than seek new ones. Understanding the cartels’ logic might make it easier to predict their movements, Rios says.




From issue 2887 of New Scientist magazine, page 12.

Destroying drug cartels, the mathematical way. By Sara Reardon

Killing drug lords gets headlines, but complexity analysis suggests they are the wrong people to target to bring down a cartel

WHEN the Mexican navy announced on 9 October that Heriberto Lazcano, leader of the country’s most violent criminal cartel, Los Zetas, had been killed it was hailed as a major victory in the war on drugs. But it’s doubtful that Lazcano’s death will be the end of Los Zetas - or reduce violence in Mexico. After all, there is already a new leader.

More useful targets might be those apparently minor players with key connections, according to a complexity analysis approach that could help Colombia - the world’s largest producer of cocaine - investigate and prosecute cartel members.

Complexity analysis depicts drugs cartels as a complex network with each member as a node and their interactions as lines between them. Algorithms compute the strength and importance of the connections. At first glance, taking out a central “hub” seems like a good idea. When Colombian drug lord Pablo Escobar was killed in 1993, for example, the Medellin cartel he was in charge of fell apart. But like a hydra, chopping off the head only caused the cartel to splinter into smaller networks. By 1996, 300 “baby cartels” had sprung up in Colombia, says Michael Lawrence of the Waterloo Institute for Complexity and Innovation in Canada, and they are still powerful today. Mexican officials are currently copying the top-down approach, says Lawrence, but he doubts it will work. “Network theory tells us how tenuous the current policy is,” he says.

Now Colombian prosecutors have a new tool to add to their investigation methods: network analysis. This can be an integral part of the modern war on drugs, says Eduardo Salcedo-Albaran, director of the Vortex Foundation based in Bogotá.

Vortex uses network-analysis algorithms to construct diagrams for court cases that show the interactions between cartel members, governors and law enforcers. These reveal links that are not otherwise visible, what Salcedo-Albaran calls “betweeners” - people who are not well-connected, but serve as a bridge linking two groups. In Mexico and Colombia, these are often police or governors who are paid by the cartels.

“The betweener is the guy who connects the illegal with the legal,” says Salcedo-Albaran. Because many cartels depend on their close ties with the law to operate successfully, removing the betweeners could devastate their operations.

It’s a reasonable strategy, says Michael Kenney of the University of Pittsburgh in Pennsylvania, although it shouldn’t be the only one governments use. The ideal strategy depends on government goals. If it is the end of the drug trade they are after, removing the leaders may work. But if the goal is to reduce violence, as incoming Mexican president Enrique Peña Nieto has vowed to do, targeting kingpins like Lazcano will have the opposite effect, says Vanda Felbab-Brown of the Brookings Institution in Washington DC. Smaller organisations that emerge from a broken cartel tend to assert their power by torturing and killing people.

Fighting all these factions would require even more firepower. Sean Gourley, of the data analysis organisation Quid in San Francisco, used public data from nine recent insurgencies, including Colombia’s drug war, to determine mathematically how these battles play out (Naturedoi.org/bv2tf5). “Unfortunately, if you put more forces on the ground, you elongate the violence,” he says.

Data collected by the Transborder Institute in San Diego, California, supports this. Prior to the crackdowns that began in 2006, drug-related crimes in Mexico killed about 3700 people per year. In 2011, that number was more than 16,000.

“People keep saying that the violence [in Mexico] will get worse before it gets better, and the cartels are at the end of their lives, but those predictions have been going on for years,” says Lawrence. At some point, he suggests, a more mathematical approach will win out.

Lost your cartel? Just Google it

Mexican cartels aren’t subtle about their whereabouts. To intimidate their rivals and the government, they advertise their latest crimes through the media and threaten each other on blogs and websites.

But this practice has been revealing their inner workings to Viridiana Rios and Michele Coscia of Harvard University. In a paper that will be presented at the CIKM conference in Hawaii this month, the two created a program called MOGO that searches Google News for references to the different cartels, their locations and their influence between 1999 and 2011.

They used MOGO to construct a map showing where all the cartels were working at each point in time. Their map turned out to be quite accurate, correlating closely with those developed by the global intelligence firmStratfor.

The cartels’ movements reveal a lot about their business strategies, says Rios. Some, such as Los Zetas, are very aggressive, expanding quickly into new territories and competing with rivals. Older organisations such as Sinaloa prefer to strengthen their own territories rather than seek new ones. Understanding the cartels’ logic might make it easier to predict their movements, Rios says.

Issue 2887 of New Scientist magazine
  • From issue 2887 of New Scientist magazine, page 12.

Mine your language: Software decodes company reports. By Douglas Heaven




COMPANY financial reports don’t usually make for thrilling reading, but with the ability to make or break fortunes, they come under intense scrutiny. Now software that can extract information from the nuanced language of such reports could provide investors with the edge they need to stay ahead of the competition.
“Financial statements carry important information about the health of reporting companies,” says Chao-Lin Liu at National Chengchi University in Taipei, Taiwan. But companies habitually downplay negative aspects by using ambiguous language and burying nuggets of information in pages of droning prose.
Text-mining techniques generally concentrate on single words: counting the number of negative or positive words in a body of text can give an indication of the overall tone, for example. But it is impossible to say whether certain words taken in isolation - such as “increased” - are positive or negative, says team member Yuan-Chen Chang. So the team designed an algorithm to recognise meaningful phrases instead (arxiv.org/abs/1210.3865).
To do this, Liu and his colleagues use statistical models to automatically identify what they call opinion patterns - subjective phrases paired with an opinion holder. For example, the sentence “The Company believes the profits could be adversely affected” contains the opinion holder “The Company” and the subjective phrases “believes” and “could be adversely affected”.
“Computer linguistics and automated textual-information processing are one of the new frontiers in the world of finance,” says Werner Antweiler of the Sauder School of Business at the University of British Columbia in Vancouver, Canada. “This technique adds another tool to our statistical toolbox of text-mining algorithms.”
Trading algorithms mostly rely on quantitative information, says Liu, “but it is obvious that textual information should be considered as well”. For example, the team’s software could flag up phrases that don’t appear to tally with a company’s stated earnings, prompting a financial analyst to take a closer look. “Numbers can be used to convey a picture that does not correspond to reality,” says Vincent Papa, director of financial-reporting policy at the CFA Institute in London. “They tend not to reveal what really keeps managers awake at night. The tone of a report is a very useful complementary piece of information.”
Murray Frank at the University of Minnesota in Minneapolis points out that sophisticated linguistic analysis is a very hard task. The software needs to learn which words are positive, which are negative and which are neither. Phrases need to appear often enough for a statistical-learning algorithm to accurately categorise them. Multi-word phrases might not occur often enough to help. “Bundles of words tend to be rare things,” he says.
The whole point of the account reporting system is to release information in a way that is fair to all investors, says Frank. “But if you can guess correctly ahead of others, you can make a lot of money.” If the team’s system provides an edge, it could prove extremely valuable.
Mining text to monitor trends and opinions in the financial world is a rapidly growing field. “Some of the news-feed providers such as Reuters already use sentiment analysis,” says Antweiler. But such technology shouldn’t be relied on for automated decisions, he warns. “The simple truth is that text mining can be helpful, but it doesn’t replace sound judgement and common sense.”

Mining for a gaming smash
The success of video games could be predicted by data mining. Christian Bauckhage at the University of Bonn, Germany, and colleagues applied pattern recognition and statistical analysis techniques to data gathered from more than 250,000 players of five blockbuster games in the months after their release. They found that the decline in frequency and time people spent playing each game fit well-known mathematical models.
If similar monitoring was done during pre-release consumer testing, game publishers could use these models to predict the popularity and lifespan of a new game once it hits the market. The work was presented at the Game/AI conference in Vienna, Austria, last month.




From issue 2889 of New Scientist magazine, page 19.

Mine your language: Software decodes company reports. By Douglas Heaven

COMPANY financial reports don’t usually make for thrilling reading, but with the ability to make or break fortunes, they come under intense scrutiny. Now software that can extract information from the nuanced language of such reports could provide investors with the edge they need to stay ahead of the competition.

“Financial statements carry important information about the health of reporting companies,” says Chao-Lin Liu at National Chengchi University in Taipei, Taiwan. But companies habitually downplay negative aspects by using ambiguous language and burying nuggets of information in pages of droning prose.

Text-mining techniques generally concentrate on single words: counting the number of negative or positive words in a body of text can give an indication of the overall tone, for example. But it is impossible to say whether certain words taken in isolation - such as “increased” - are positive or negative, says team member Yuan-Chen Chang. So the team designed an algorithm to recognise meaningful phrases instead (arxiv.org/abs/1210.3865).

To do this, Liu and his colleagues use statistical models to automatically identify what they call opinion patterns - subjective phrases paired with an opinion holder. For example, the sentence “The Company believes the profits could be adversely affected” contains the opinion holder “The Company” and the subjective phrases “believes” and “could be adversely affected”.

“Computer linguistics and automated textual-information processing are one of the new frontiers in the world of finance,” says Werner Antweiler of the Sauder School of Business at the University of British Columbia in Vancouver, Canada. “This technique adds another tool to our statistical toolbox of text-mining algorithms.”

Trading algorithms mostly rely on quantitative information, says Liu, “but it is obvious that textual information should be considered as well”. For example, the team’s software could flag up phrases that don’t appear to tally with a company’s stated earnings, prompting a financial analyst to take a closer look. “Numbers can be used to convey a picture that does not correspond to reality,” says Vincent Papa, director of financial-reporting policy at the CFA Institute in London. “They tend not to reveal what really keeps managers awake at night. The tone of a report is a very useful complementary piece of information.”

Murray Frank at the University of Minnesota in Minneapolis points out that sophisticated linguistic analysis is a very hard task. The software needs to learn which words are positive, which are negative and which are neither. Phrases need to appear often enough for a statistical-learning algorithm to accurately categorise them. Multi-word phrases might not occur often enough to help. “Bundles of words tend to be rare things,” he says.

The whole point of the account reporting system is to release information in a way that is fair to all investors, says Frank. “But if you can guess correctly ahead of others, you can make a lot of money.” If the team’s system provides an edge, it could prove extremely valuable.

Mining text to monitor trends and opinions in the financial world is a rapidly growing field. “Some of the news-feed providers such as Reuters already use sentiment analysis,” says Antweiler. But such technology shouldn’t be relied on for automated decisions, he warns. “The simple truth is that text mining can be helpful, but it doesn’t replace sound judgement and common sense.”

Mining for a gaming smash

The success of video games could be predicted by data mining. Christian Bauckhage at the University of Bonn, Germany, and colleagues applied pattern recognition and statistical analysis techniques to data gathered from more than 250,000 players of five blockbuster games in the months after their release. They found that the decline in frequency and time people spent playing each game fit well-known mathematical models.

If similar monitoring was done during pre-release consumer testing, game publishers could use these models to predict the popularity and lifespan of a new game once it hits the market. The work was presented at the Game/AI conference in Vienna, Austria, last month.

Issue 2889 of New Scientist magazine
  • From issue 2889 of New Scientist magazine, page 19.
Virtual germ created on computer for first time. By Paul Marks
C0134775-Mycoplasma_genitalium_bacteria,_SEM.jpg

(Image: Thomas Deernick, NCMIR/Science Photo Library)

In a move that promises to bring the advantages of computer aided design (CAD) to genetic engineers, the first computer model of a complete bacterium has been produced in the US. It means researchers will soon be able to modify models of an organism’s genome on a computer screen - or create artificial lifeforms - without the risks of undertaking wet biology in secure biosafety labs.

The pathogen is called Mycoplasma genitalium, a bacterium implicated in a number of urethral and vaginal infections. The bug was ripe for modelling say researchers at Stanford University in California, because it has the smallest genome of any free-living organism, with just 525 genes. By contrast, the popular lab pathogen E. coli has 4288 genes.

The modelling was undertaken by bioengineer Markus Covert and colleagues. To get the raw data for their model, they undertook an exhaustive literature review - spanning 900 research papers - to allow them to program into their model some 1900 experimentally observed behaviours and molecular interactions that M. genitalium can take part in during its life cycle.

In software terms, they found the behaviours of the 525 genes could be described by 28 algorithms, each governing the behaviour of a software module modelling a different biological process. “These modules then communicated with each other after every time step, making for a unified whole that closely matched M. genitalium’s real-world behaviour,” claims the Stanford team in a statement. Their research appears in the journal Cell (doi: 10.1016/j.cell.2012.05.044).

Such models will ultimately give biologists the freedom to undertake “what if” scenarios common in regular engineering - changing parameters in a genome design, say, like a civil engineer adjusts the width of a bridge deck on a computer to see what happens. As well as being experimentally useful, allowing artificial organisms and synthetic lifeforms to be created virtually (harming no-one), they could also boost biosafety by preventing accidental creations of lethal pathogens. In 2001, for instance, researchers in Australia accidentally created a lethal strain of mousepox.

In a commentary article in Cell, systems biologists Peter Freddolino and Saeed Tavazoie of Columbia University say they hope the work will soon be extended to more commonly used lab bugs like E. coli - but also warn that the technique’s accuracy has yet to be demonstrated. It is unclear, they say, “how well overall behaviors will be predicted from a collection of separately obtained parameters” gleaned from hundreds of research papers.

But the US National Institutes of Health, which funded the modelling work, is excited. It believes the model a major step towards finding “new approaches for the diagnosis and treatment of disease”, says James Anderson, an NIH program director.t 

Molecules from scratch without the fiendish physics. By Lisa Grossman

A SUITE of artificial intelligence algorithms may become the ultimate chemistry set. Software can now quickly predict a property of molecules from their theoretical structure. Similar advances should allow chemists to design new molecules on computers instead of by lengthy trial-and-error.

Our physical understanding of the macroscopic world is so good that everything from bridges to aircraft can be designed and tested on a computer. There’s no need to make every possible design to figure out which ones work. Microscopic molecules are a different story. “Basically, we are still doing chemistry like Thomas Edison,” says Anatole von Lilienfeld of Argonne National Laboratory in Lemont, Illinois.

The chief enemy of computer-aided chemical design is the Schrödinger equation. In theory, this mathematical beast can be solved to give the probability that electrons in an atom or molecule will be in certain positions, giving rise to chemical and physical properties.

But because the equation increases in complexity as more electrons and protons are introduced, exact solutions only exist for the simplest systems: the hydrogen atom, composed of one electron and one proton, and the hydrogen molecule, which has two electrons and two protons.

This complexity rules out the possibility of exactly predicting the properties of large molecules that might be useful for engineering or medicine. “It’s out of the question to solve the Schrödinger equation to arbitrary precision for, say, aspirin,” says von Lilienfeld.

So he and his colleagues bypassed the fiendish equation entirely and turned instead to a computer-science technique.

Machine learning is already widely used to find patterns in large data sets with complicated underlying rules, including stock market analysis, ecology and Amazon’s personalised book recommendations. An algorithm is fed examples (other shoppers who bought the book you’re looking at, for instance) and the computer uses them to predict an outcome (other books you might like). “In the same way, we learn from molecules and use them as previous examples to predict properties of new molecules,” says von Lilienfeld.

His team focused on a basic property: the energy tied up in all the bonds holding a molecule together, the atomisation energy. The team built a database of 7165 molecules with known atomisation energies and structures. The computer used 1000 of these to identify structural features that could predict the atomisation energies.

When the researchers tested the resulting algorithm on the remaining 6165 molecules, it produced atomisation energies within 1 per cent of the true value. That is comparable to the accuracy of mathematical approximations of the Schrödinger equation, which work but take longer to calculate as molecules get bigger (Physical Review LettersDOI: 10.1103/PhysRevLett.108.058301).

The algorithm found solutions in a millisecond that would take these earlier methods an hour. “Instead of having to wait years to screen lots of new molecules, you might have to wait weeks or a month,” says Mark Tuckerman of New York University, who was not involved in the new work.

The algorithm is still mainly a proof of principle. If it can learn to predict something else, such as how well a molecule binds to an enzyme, it could help with designing drugs, fuel cells, batteries or biosensors. “The applications can be as broad as chemistry,” von Lilienfeld says.

free counters