Cognitive Training

Sunday, March 31st, 2013

Video games often try to be “realistic” by getting the details right in how everything looks and sounds, but this physical fidelity isn’t as important in a training simulation as cognitive fidelity, Daniel Gopher explains:

My main inter­est has been how to expand the lim­its of human atten­tion, infor­ma­tion pro­cess­ing and response capa­bil­i­ties which are crit­i­cal in com­plex, real-time decision-making, high-demand tasks such as fly­ing a mil­i­tary jet or play­ing pro­fes­sional bas­ket­ball. Using a ten­nis anal­ogy, my goal has been, and is, how to help develop many “Wimbledon”-like cham­pi­ons. Each with their own styles, but per­form­ing to their max­i­mum capac­ity to suc­ceed in their environments.

What research over the last 15–20 years has shown is that cog­ni­tion, or what we call think­ing and per­for­mance, is really a set of skills that we can train sys­tem­at­i­cally. And that computer-based cog­ni­tive train­ers or “cog­ni­tive sim­u­la­tions” are the most effec­tive and effi­cient way to do so.

This is an impor­tant point, so let me empha­size it. What we have dis­cov­ered is that a key fac­tor for an effec­tive trans­fer from train­ing envi­ron­ment to real­ity is that the train­ing pro­gram ensures “Cog­ni­tive Fidelity”, this is, it should faith­fully rep­re­sent the men­tal demands that hap­pen in the real world. Tra­di­tional approaches focus instead on phys­i­cal fidelity, which may seem more intu­itive, but less effec­tive and harder to achieve. They are also less effi­cient, given costs involved in cre­at­ing expen­sive phys­i­cal sim­u­la­tors that faith­fully repli­cate, let’s say, a whole mil­i­tary heli­copter or just a sig­nif­i­cant part of it.


The need for phys­i­cal fidelity is not based on research, at least for the type of high-performance train­ing we are talk­ing about. In fact, a sim­ple envi­ron­ment may be bet­ter in that it does not cre­ate the illu­sion of real­ity. Sim­u­la­tions can be very expen­sive and com­plex, some­times even cost­ing as much as the real thing, which lim­its the access to train­ing. Not only that, but the whole effort may be futile, given that some impor­tant fea­tures can not be repli­cated (such as grav­i­ta­tion free tilted or inverted flight), and even result in neg­a­tive trans­fer, because learn­ers pick up on spe­cific train­ing fea­tures or sen­sa­tions that do not exist in the real situation.


In one [study], which con­sti­tuted the basis for the 1994 paper, we showed that 10 hours of train­ing for flight cadets, in an atten­tion trainer instan­ti­ated as a com­puter game — Space Fortress — resulted in 30% improve­ment in their flight per­for­mance. The results led the trainer to be inte­grated into the reg­u­lar train­ing pro­gram of the flight school. It was used in the train­ing of hun­dreds of flight cadets for sev­eral years. In the other one, spon­sored by NASA, we com­pared the results of the cog­ni­tive trainer vs. a sophis­ti­cated, pic­to­r­ial and high-level-graphic and physical-fidelity-based com­puter sim­u­la­tion of a Black­hawk heli­copter. The result: the Space Fortress cog­ni­tive trainer was very suc­cess­ful in improv­ing per­for­mance, while the alter­na­tive was not. The study was pub­lished in the pro­ceed­ings of the Human Fac­tors and Ergonomic Soci­ety: Hart S. G and Bat­tiste V. (1992), Flight test of a video game trainer. Pro­ceed­ings of the Human Fac­tors Soci­ety 26th Meet­ing (pp. 1291–1295).

This led to IntelliGym‘s basketball training software:

In order to develop a basketball cognitive training tool, our researchers mapped the brain skills that are required for top performance in the game of basketball. These include (among others) reading plays, positioning, decision making, team work, and execution under pressure. Together, they constitute what is usually referred to as game intelligence. With this map in hand, the researchers designed a system that simulates the exact same skill set.

IntelliGym Basketball

The Morris Theorem

Saturday, March 30th, 2013

This profile of Ian Morris boils down his thinking to a simple Morris Theory of social behavior:

“Change is caused by lazy, greedy, frightened people looking for easier, more profitable, and safer ways to do things.” These people are much the same everywhere. Their societies develop along similar paths. Geography explains different outcomes. “Maps, not chaps,” as Morris likes to say.

“The agency of individuals actually matters much less than historians tend to assume,” Morris tells me. “It’s hard to find any examples of decisions made by single individuals that really changed the big story very much — until you get into the 20th century, when you’ve got nuclear weapons.”

Task Force 714

Friday, March 29th, 2013

Stanley McChrystal explains how his special operations task force tightened its OODA loop:

I was part of a [special operations] effort that we can call Task Force 714. When the counterterrorist effort against al Qaeda started, it was narrowly focused and centralized; you only did occasional operations with a high degree of intelligence and a tremendous amount of secrecy. That worked well for the pre-9/11 environment, but in the post-9/11 environment — particularly the post-March 2003 environment in Iraq — the breadth of al Qaeda and associated movements exploded. This gave us an enemy network that you couldn’t just react to but actually had to dismantle. It also gave us a very complex battlefield — not just terrorism but also social problems, an insurgency, and sectarian violence.

So the first thing we did when I took over in late 2003 was realize that we needed to understand the problem much better. To do that, we had to become a network ourselves — to be connected across all parts of the battlefield, so that every time something occurred and we gathered intelligence or experience from it, information flowed very, very quickly.

The network had a tremendous amount of geographical spread. At one point, we were in 27 countries simultaneously. Inside Iraq, we were in 20 and 30 places simultaneously — all connected using modern technology but also personal relationships. This gave us the ability to learn about the constantly evolving challenge.

People hear most about the targeting cycle, which we called F3EA — “find, fix, finish, exploit, and analyze.” You understand who or what is a target, you locate it, you capture or kill it, you take what intelligence you can from people or equipment or documents, you analyze that, and then you go back and do the cycle again, smarter.

When we first started, those five steps were performed by different parts of our organization or different security agencies. And as a consequence, each time you passed information from one to another, it would be like a game of telephone, so that by the time information got to the end, it would be not only slow but also corrupted. We learned we had to reduce the number of steps in the process.

In 2003, in many cases we’d go after someone, we might locate them and capture or kill them, and it would be weeks until we took the intelligence we learned from that and were able to turn it into another operation. Within about two years, we could turn that cycle three times in a night. We could capture someone, gain intelligence from the experience, go after someone else, and do three of those in a row, the second two involving people we didn’t even know existed at the beginning of the night.

In August 2004, in all of Iraq, our task force did 18 raids. And we thought that was breakneck speed. I mean, we really thought we had the pedal to the metal. These were great raids, very precise, a high percentage of success. But as great as those 18 raids were, they couldn’t make a dent in the exploding insurgency. Two years later, in August 2006, we were up to 300 raids a month — ten a night. This meant the network now had to operate at a speed that was not even considered before, not in our wildest dreams. It had to have decentralized decision-making, because you can’t centralize ten raids a night. You have to understand them all, but you have to allow your subordinate elements to operate very quickly.

But then, we had to be able to take all of that and make it mean something — because it’s not just about capturing and killing people; it’s about synchronizing into the wider theater campaign. And that took us longer. We really didn’t mesh completely into the conventional war effort [in Iraq] until 2006, 2007.

The Evolution of War

Friday, March 29th, 2013

Ian Morris describes the evolution of war:

War and governance have co-evolved across the last 15,000 years, but much remains unclear about the process because historical narratives have not been integrated well into social-scientific analyses. Under the conditions of circumscription/caging that emerged in a few places after the ice age, war became productive, in the sense of producing larger, safer, richer societies. However, the larger states produced by war changed the environment around them, and for more than 1,000 years war turned counterproductive in the places that it had previously been productive, breaking up large states. After about 1400 CE a new phase of productive war began. This too began turning counterproductive in the 20th century CE. The most important question for the 21st century is whether productive war is currently mutating into a new form.

Read the whole thing.

Owning a Dire Wolf

Thursday, March 28th, 2013

American AlsatianReal dire wolves (Canis dirus) died out 10,000 years ago. They were more robustly built than modern gray wolves, weighing a quarter more, and able to take down the megafauna prey of their time.

The fantastical dire wolves of HBO’s Game of Thrones are played by Northern Inuit Dogs, which have been bred to resemble gray wolves.

Now the American Alsatian Breeders Association has started its own Dire Wolf Project to combine the look of the extinct dire wolf with the temperament of a domesticated companion dog:

Topping out at 130 pounds, American Alsatians are not quite up to dire wolf size, but in that regard Schwarz says the breed will be informed more by practicality than accuracy. Few families are looking for a 160-pound dog, and Schwarz is anxious to avoid American Alsatians ending up at the pound.

And what Schwarz’s dogs lack in prehistoric dire wolf minutiae, they make up for with their pleasant temperament. The cluster of characteristics she claimed to be able to breed for consistently — intelligent, alert pups who would seek human contact but sit calmly instead of chasing or barking — seemed unlikely, especially for a breed whose ancestors were primarily working dogs.

Then, I met my first American Alsatian puppies. At four weeks, they crawled up wide-eyed and alert to investigate my shoes, as their mother Autumn sat patiently by.

“Watch this,” Schwarz told me. “This is a temperament test.” She dropped a large chest of tools on the ground with a clang. I jumped, but the puppies just glanced lazily over before continuing about their business. Even as puppies, American Alsatians are noticeably calm, whether they’re exploring their environment or scooped up in your arms; it’s easy to believe Schwarz’s claim that many end up companion or therapy dogs for owners with special needs.

So how close are they to actual dire wolves? Extinct canid expert Xiaoming Wang of the Vertebrate Paleontology Department at the Natural History Museum of Los Angeles told Wired that an actual genetic connection is very unlikely, given that dogs originated much later than — and on a different continent from — dire wolves. And Schwarz herself admits that the reconstruction on which she’s basing the breed’s coat and stature are more wishful and fantasy-oriented than scientific, matched more to the needs of prospective owners than prehistoric fact.

Still, if what you’re after is a friendly, mellow dog with that shaggy, fantasy-wolf look, an American Alsatian might be your best bet. Don’t get too excited, though: Even if you can hack the $3,000 price tag, there’s a long waiting list for puppies, which Schwarz expects will get even longer as more Game of Thrones fans find their way to her kennels.

I may need a bigger yard.

War Forges Civilization

Thursday, March 28th, 2013

Warfare has transformed us from living in villages to living in huge states, Peter Turchin argues — ultimately making our lives more peaceful:

First, the critical glue that holds societies together is cooperation. Second, the reason humans learned how to cooperate is — paradoxically — warfare, lethal conflict between groups. And third, by creating a selective pressure for ever-larger societies warfare will eventually put itself out of business, when we learn to cooperate at the level of the whole humanity.

When he argued this at a public debate, the audience sounded voted for the opposing side. War is bad, after all.

His first two points seem reasonable. His third reminds me of the underwear gnomes’ business plan — or Marx’s notion that the state will wither away under true Communism. (Unless we can expect an alien invasion…)

Humans are ultrasocial (his first point), and the logic for why (his second point) is simple:

Groups of people who can’t cooperate to put together an army, will be overrun by those who can. The result is that genetic and cultural traits for noncooperation will go extinct.

More generally, cooperative traits are spread by the process of group selection. Selfish traits win in competition within groups, but altruistic, cooperative traits are favored by competition between groups. If between groups selection is strong enough, cooperative traits will spread.

Human groups can compete in many ways, but historically the most extreme form of such competition has been warfare. Warfare is the main engine of social evolution and it explains how small bands of hunter-gatherers (a few dozen people) evolved over the last 10,000 years into the huge societies of today. Because warfare pushes cooperating groups to become larger. As Napoleon said, “God favors big battalions.” The tribe that could mobilize more warriors had a better chance of surviving in war. This is the basic logic that drove the evolution of ever greater societies and states, and ever greater scale of warfare.

The story is of course much more complex than that. First, before warfare could do its thing, humans had to invent agriculture. Agriculture is a necessary condition for the evolution of truly complex societies. Why is absolutely obvious, and all scientists, including the participants of this debate, agree on it. But agriculture is only a necessary, not sufficient condition — many regions of the world had agriculture for milennia and did not make the transition to complex societies until they were colonized by European Great Powers.

Second, evolution had to solve a multitude of problems in order to ensure that large societies would not simply split apart at the seams (in fact, most early states and empires did just that). So such cultural traits as monumental architecture; records, writing, and literacy; division of labor; professional bureaucracies, taxation, and formal legal systems; state rituals and ideologies, and so on, evolved to enable megasocieties to function without falling apart. But the fundamental driver was warfare.

However not any kind of warfare has this ‘creative’ nature. It doesn’t matter how many people are killed, what is important is the high chance of group extinction. This is what drives social evolution. In the mountains, for example, warfare does not drive evolution of social complexity. So you lose a battle, but you can always survive by retreating to a mountain fastness. The chance of extinction is small, and in rugged areas complex societies do not evolve. The opposite thing happens. People living there evolve away from the state.

In the plains, on the other hand, if you lose the war, you are history.

Although large societies fight big wars, citizens in such societies have a much lesser chance of being killed by other human beings:

One reason is that strong states suppress internal warfare, banditry, and murder. Another is that among hunter-gatherers everybody (at least, all males) had to be a warrior, but in large-scale societies, typically, only a small proportion fights in wars. The chances that you or I will get killed are much smaller.

More importantly, social evolution molded humans in ways that reduce violence. Earlier I mentioned that most people have a very strong aversion to killing fellow human beings. It was the same at the dawn of humanity, except ‘fellow human beings’ were only those personally known to you — relatives and friends. Or members of your tribe. Others were subhumans who needed to be exterminated.

Turchin cites Ian Morris (Why the West Rules — For Now):

The late historical sociologist Charles Tilly coined the phrase, “war made the state, and the state made war.”

Ian Morris prefers a different variant: “war made the state, and the state made peace.”

This is an uncomfortable conclusion:

But nobody proposes that we administer a “healthy dose” of “blood and iron” (to use the immortal phrase of the Prussian Chancellor Otto von Bismarck) to encourage state building in such places as equatorial Africa. In fact, many African countries are already mired in an endless cycle of war. Not only such violence causes a huge amount of human misery, it has done nothing for bringing about more effective governance. On the contrary, in a number of places warfare destroyed the last vestiges of state-level organization.

So, there are productive and unproductive wars. The Lucky Latitudes, where agriculture took off early, on balance favored productive war:

The size of empires increased during the Bronze and Iron Ages (roughly, the second and first milennia BC).

Empires Sizes Over Time

It increased especially rapidly during the centuries between 800 and 200 BC. Then it stopped increasing. Ian actually suggests that the size of empires decreased between 1 AD and 1415 AD. It doesn’t look that way to me, but it is undeniable that the size of largest empires stopped increasing — empires rose and collapsed but the areas they controlled at the peak oscillated around 3 million square kilometers — the size of modern India or Argentina. The two peaks you see in the eighth and thirteenth centuries are the Islamic Caliphate and the Mongolian Empire of Chinggis Khan and his successors. Neither was sustained for very long.

Ian’s conclusion is that before 1 BC warfare in the Lucky Latitudes was, on balance, productive, but between 1 AD and the end of the Middle Ages it was (again, on balance) counterproductive. The culprit was the horse nomad from the steppes. As Ian says in the Cliodynamics article, “the success of the empires of the Eurasian lucky latitudes had changed the meanings of geography in radical ways, with disastrous results.” The rise of steppe pastoralists, and their disastrous effect on the agrarian societies, was a kind of a ‘blowback’ response when the great agrarian empires overreached themselves.

It’s not war in itself that is either productive or unproductive, but competition between groups and societies:

Violence is unproductive when it pitches people against other people within societies, taking forms such as murders between individual people or civil war between organized groups. It can be ‘productive,’ despite killing people and destroying property, when it is whole societies fighting other societies. But the key is not killing people, it’s between-group selection — competition that eliminates societies, whose members are unable to cooperate with each other, or to invent and adopt innovations and acquire or sustain prosocial norms and institutions. It’s not being good at killing.


Conversely, high rates of violence, as those found in the Inuit (where 30 percent of adult male deaths were due to murders), or incessant between-village warfare in New Guinea and the Amazon (Yanomami!) have been completely unproductive for the evolution of large-scale cohesive and productive societies.

Red White

Wednesday, March 27th, 2013

As the chief architect of the Bretton Woods monetary system, Harry Dexter White, then a little-known U.S. Treasury official, outmaneuvered his brilliant British counterpart, John Maynard Keynes, to produce a New Deal for a new world that protected American interests — and Soviet interests:

Over the course of 11 years, beginning in the mid-1930s, White acted as a Soviet mole, giving the Soviets secret information and advice on how to negotiate with the Roosevelt administration and advocating for them during internal policy debates. White was arguably more important to Soviet intelligence than Alger Hiss, the U.S. State Department official who was the most famous spy of the early Cold War.

The truth about White’s actions has been clear for at least 15 years now, yet historians remain deeply divided over his intentions and his legacy, puzzled by the chasm between White’s public views on political economy, which were mainstream progressive and Keynesian, and his clandestine behavior on behalf of the Soviets. Until recently, the White case has resembled a murder mystery with witnesses and a weapon but no clear motive.

Now we have one. The closest thing to a missing link between the official White and the secret White is an unpublished handwritten essay on yellow-lined notepaper that I found buried in a large folder of miscellaneous scribblings in White’s archives at Princeton University. Apparently missed by his previous chroniclers, it provides a fascinating window onto the aspirations and mindset of this intellectually ambitious overachiever at the height of his power, in 1944.

In the essay, hazily titled “Political-Economic Int. of Future,” White describes a postwar world in which the Soviet socialist model of economic organization, although not supplanting the American liberal capitalist one, would be ascendant. “In every case,” he argues, “the change will be in the direction of increased [government] control over industry, and increased restrictions on the operations of competition and free enterprise.” Whereas White believed in democracy and human rights, he consistently downplayed both the lack of individual liberty in the Soviet Union (“The trend in Russia seems to be toward greater freedom of religion. . . . The constitution of [the] USSR guarantees that right”) and the Soviets’ foreign political and military adventurism (“The policy pursued by present day Russia [is one] of not actively supporting [revolutionary socialist] movements in other countries”).

In the essay, White argues that the West is hypocritical in its demonization of the Soviet Union. He urges the United States to draw the Soviets into a tight military alliance in order to deter renewed German and Japanese aggression. But such an alliance, White lamented, faced formidable obstacles: “rampant imperialism” in the United States, hiding under “a variety of patriotic cloaks”; the country’s “very powerful Catholic hierarchy,” which might “well find an alliance with Russia repugnant”; and groups “fearful that any alliance with a socialist country cannot but strengthen socialism and thereby weaken capitalism.”

After sweeping away internal politics, religion, and foreign policy as honest sources of Western opposition to the Soviet Union, White concludes that the true foundation of the conflict must be economic ideology. “It is basically [the] opposition of capitalism to socialism,” he writes. “Those who believe seriously in the superiority of capitalism over socialism” — a group from which White apparently excluded himself — “fear Russia as the source of socialist ideology.” He then ends his essay with what, coming from the U.S. government’s most important economic strategist, can only be described as an astounding conclusion: “Russia is the first instance of a socialist economy in action. And it works!”

It turns out that the chief designer of the postwar global capitalist financial architecture saw Soviet behavior through rose-colored glasses not simply because he believed that the Soviet Union was a vital U.S. ally but because he also believed passionately in the success of the bold Soviet experiment with socialism.

I am shocked — shocked! — to find that a mainstream progressive supported Soviet Communism.

(Hat tip to Foseti, who notes that none of this was unknown at the time, but only crazy people believed it.)

The Glue that Binds

Wednesday, March 27th, 2013

As a professor, Peter Turchin finds himself strong-armed into attending graduation every few years, which reminds him of his childhood in Soviet Moscow, where he and his neighbors had to line the streets and welcome visiting dignitaries.

After meeting anthropologist Harvey Whitehouse though, he finds such rituals make a certain kind of sense:

A ritual is something that takes place at two levels. There are surface reasons why people do it, but much more important is the deeper, concealed layer, “the hidden side of things” to which I referred in the beginning of the post.

Consider a ritual such as Mardi Gras, in which I participated on numerous occasions when I lived in Louisiana. It’s a lot of fun — parades, music, dancing, feasting, drinking to excess, and (reportedly) wild sex!

In the anthropologist jargon, this is a “euphoric” ritual. Such rituals are extremely common in human societies, they could even be a universal feature (well, there are exceptions, such as Jean Calvin’s Geneva, but they don’t last long). The reason people take part in such euphoric rituals is because it’s fun. But there is also a much more important – hidden – reason, about which the participants don’t have any inklings. Such rituals make people feel connected to each other. They provide a quintessential psychological glue that binds a community together, and makes it much more capable of collective action. And, naturally, communities that are socially cohesive will be much more likely to survive in the competition against other, less cohesive groups.

This logic of cultural group selection is even clearer when we consider the opposite kind of ritual, which Harvey and other anthropologists call ‘dysphoric’, involving painful, frightening, disgusting, or humiliating features. It’s easy enough to understand why people flock to a Mardi Gras celebration, but why is hazing in the military or fraternities so prevalent and difficult to eradicate? Why do initiates agree to undergo painful, degrading, and even life-risking ordeals?

It turns out that the answer, when we look not for a proximate, surface explanation, but for an ultimate, deep and evolutionary one, is the same. Shared experience in dysphoric rituals results in incredibly strong ties binding the group into one cohesive whole. This is why the military puts recruits through the boot camps. Unit cohesion and willingness to sacrifice one’s life for buddies makes for an army that will fight effectively and defeat its less cohesive opponents.
This means that rituals are not simply actions performed for their ‘symbolic value.’ Rather, rituals are psychological devices for building up social cohesion. On the surface, a ritual could be fun, or alternatively, an harrowing ordeal, but at the deeper level they all serve the same function – making groups more internally cohesive so they can more effectively compete against other groups.

Speaking of the graduation procession, he adds, it’s quite remarkable how we humans enjoy moving synchronously with others.

Book Publishers Scramble to Rewrite Their Future

Tuesday, March 26th, 2013

Publishers fear cultural irrelevance:

“The fact is that people don’t read anymore,” Steve Jobs told a reporter in 2008, blurting out the secret fear of bookish people everywhere. But consider this: In one week, people who don’t read anymore bought about half a million copies of a really long book called Steve Jobs. In the past year, Vintage has sold one book from the Fifty Shades of Grey trilogy for every six American adults. The Big Six publishers — Random House, Penguin, Hachette, Macmillan, Simon & Schuster, and HarperCollins — all make money, and at profit margins that are likely better than they were 50 years ago.

Meanwhile, readers have an unprecedented array of options. E-readers have gotten consistently cheaper and better since the first Kindle shipped in 2007, giving customers instant access to millions of titles. For a couple of dollars you can buy a self-published sensation or a Kindle Single rather than a full-length book. Add it all together and you have a more vibrant market for literary material than ever before, with nearly 3 billion copies sold every year. Amazon likes to point out that new Kindle buyers go on to purchase almost five times as many books from Amazon, print and digital, in the ensuing year as they did in the prior one. “I believe we’ll look back in five years,” says Russ Grandinetti, VP of Kindle content for Amazon, “and realize that digital was one of the great expansions of the publishing business.”

For all the digital optimism, not even Amazon is ready to declare the traditional model dead. In May 2011 the company announced that it was going head-to-head with the Big Six by launching a general-interest imprint in Manhattan, headed by respected industry veteran Larry Kirshbaum. It signed up celebrity authors, paying a reported $850,000 for a memoir by Laverne & Shirley star Penny Marshall and winning over best-selling self-help author Timothy Ferriss. Tired of being undersold by Amazon and wary of its encroachment into their business, many brick-and-mortar booksellers refused to stock the titles. The boycott has worked so far: Marshall’s book flopped, and Ferriss’ undersold his previous offering. Ferriss says he doesn’t regret his experiment with Amazon Publishing, but he allows, “I could have made more money — certainly up to this point — by staying with Random House.”

Still, it’s not clear that traditional publishers are well positioned to own the digital future. They are saddled with the costs of getting dead trees to customers — paper, printing, binding, warehousing, and shipping — and they cannot simply jettison those costs, because that system accounts for roughly 80 percent of their business. Ebooks continue to gain ground, but the healthiness of the profit margins is unclear. J. K. Rowling’s latest book helps illustrate this bind. At a rumored advance of $7 million, Little, Brown essentially backed up an armored car to Rowling’s house to pay her before seeing a nickel in revenue. The publisher then paid highly trained people to improve the novel and well-connected people to publicize and market it until it was inescapable. Little, Brown’s landlord in Manhattan occasionally asks for rent too. If a reader can buy the Kindle edition for $8.99, the public might eventually find it absurd to pay $19.99 for a printed version, let alone the $35 that Little, Brown wants for the hardcover.

Psychohistory and Cliodynamics

Tuesday, March 26th, 2013

Peter Turchin discusses the differences between Asimov’s imaginary psychohistory and his own real cliodynamics:

Asimov wrote Foundation in the 1940s — way before the discovery of what we now call ‘mathematical chaos.’ In Asimov’s book, Hari Seldon and psychohistorians develop mathematical methods to make very precise predictions years and decades in advance. Due to discoveries made in the 1970s and 80s we know that this is impossible.

In Asimov books Psychohistory, quite appropriately, deals not with individuals, but with huge conglomerates of them. It basically adopts a ‘thermodynamic’ approach, in which no attempt is made to follow the erratic trajectories of individual molecules (human beings), but instead models averages of billions of molecules. This is in many ways similar to the ideas of Leo Tolstoy, and indeed to cliodynamics, which also deals with large collectives of individuals.

What Asimov did not know is that even when you can ignore such things as individual free will, you still run against very strict limits to predictability.


In addition to the impassivity of precisely predicting the future, Asimov insisted that any knowledge of psychohistorian predictions must be kept hidden from the people. Otherwise, when people learn what is in store, that will affect their actions and cause the prediction to fail. There are several things wrong with it. For one, most people couldn’t care less about what some egg headed scientist predicts. For example, I feel quite safe making the prediction that there will be a peak of political violence in 2020 (plus/minus a few years). If this prediction fails, it will be a result of the theory going wrong, or some massive unforeseen event affecting the social system, or something completely unforeseen (the “unknown unknowns,” in the brilliant characterization of Donald Rumsfeld). But I am fairly certain it will not be because the American policy makers suddenly take a note of what an obscure professor wrote and take action to avoid this undesirable outcome.

And if they do, I will be quite happy. Prediction is overrated. What we really should be striving for, with our social science, is ability to bring about desirable outcomes and to avoid unwanted outcomes. What’s the point of predicting future, if it’s very bleak and we are not able to change it? We would be like the person condemned to hang before sunrise – perfect knowledge of the future, zero ability to do anything about it.

Resurrecting A Forest

Monday, March 25th, 2013

When Europeans arrived in North America, they found forests filled with American chestnut trees:

These mighty plants, which could grow to be 100 feet tall, were the most abundant trees in the forests, making up 25 percent of the standing timber of the eastern United States. In the summer, the peaks of Appalachian mountains appeared to be capped with snow, thanks to the explosion of white chestnut flowers. Chestnut trees anchored the ecosystems of eastern American forests, providing food and shelter to bears, Carolina parakeets, and a vast number of other species. They were also a mainstay of loggers, who could fill an entire train car with boards cut from a single tree.

In 1904, a scientist observed that a chestnut tree at the Bronx Zoo was dying. It turned out to be infected with a fungus that came to be known as chestnut blight. No one is quite sure how it got to the United States, but all the evidence we have indicates it hitch-hiked its way in the 1870s on chestnut trees imported from Japan.

Chestnut blight, while harmless to Asian trees, proved devastating to the American ones. The fungi released a toxic substance called oxalic acid that killed off the tissue, allowing them to feed on it. An infected tree developed cankers on its trunk, and once they spread around the full circumference of a tree, it could no longer carry water and nutrients from its roots to its branches.

Chestnut Blight

Over the course of about eighty years, the chestnut blight spread across almost the entire range of the American chestnut, from Maine to Missippi. It conquered nine million acres and infected three billion trees. A few lone trees still survive unharmed here and there, but no one under the age of sixty has ever seen the forests of the eastern United States as they once were.

In the pantheon of extinction, American chestnuts are poised awkwardly at the door. Chestnut blight doesn’t kill the trees outright; as it spreads down to the roots, it encounters other microbes that outcompete it. As a result, infected trees become stumps. Sometimes they send up a new shoot, but once it reaches a few feet in height, the fungus attacks it again, and the shoot dies back.

Chestnut Backcross Diagram

In the 1980s, a group of scientists embarked on a different approach, one that is now showing signs of success. If they couldn’t stop the blight, they would help the trees defend themselves.

The reason that chestnut blight was able to come to America in the first place was that Asian chestnuts can fight the fungus. They have genes that allow them to hold the cankers in check and scar them over. The trees can continue to grow and produce pollen and seeds. American chestnuts, evolving thousands of miles across the Pacific, never got the opportunity to evolve defenses against the blight. So the American Chestnut Foundation, a non-profit established to save the tree, decided to start breeding the two trees together, to see if they could provide the American chestnuts with Asian defenses.

When the foundation’s scientists interbred the American and Asian trees, the plants mixed together their genes in different combinations in their hybrid seeds.

Unusually Vulnerable to Political Violence

Monday, March 25th, 2013

Peter Turchins opens his Conversation piece on cliodynamics with this hook:

They say history always repeats itself — empires rise and fall, economies boom and bust — but is there a way to map and predict the dynamical processes of history? The new and highly controversial discipline cliodynamics is the most recent attempt to transform history into science.

When the French Assembly of Notables frustrated attempts by the royal government to fix the state fiscal crisis in 1788, because they did not want to pay taxes, these aristocrats did not intend to trigger the French Revolution, during which many of them ended up guillotined or exiled. Yet this is precisely what happened.

When the slave-owning elites of South Carolina declared their secession from the Federal Union in December 1860, they did not intend to trigger a bloody civil war that caused more than 600,000 deaths, killed one quarter of military-aged white Southerners, and resulted in the loss of most of their own wealth, when their slaves were freed. Yet this is precisely what happened.

Now, when the radical Tea Party Republicans refuse to negotiate with the Democrats to achieve a compromise, they probably don’t intend to push the United States into default, trigger a massive economic crisis, widespread urban riots, political assassinations and terrorism, and bloody clashes between the Tea Party and the Occupy Movement. Yet — well, this hasn’t happened but cliodynamics indicates that during the next decade the United States will be unusually vulnerable to an outbreak of serious political violence.

F-1 Engine Recovery

Sunday, March 24th, 2013

I don’t know what to say about the Bezos expedition to recover the F-1 engines used in the Apollo program, but it does give off a very Jonny Quest vibe.

Bezos Expedition

Intraelite Competition

Sunday, March 24th, 2013

One of the most important variables in Peter Turchin’s take on structural-demographic theory is intraelite competition:

How do we operationalize this quantity? In his 1991 book Jack Goldstone made a brilliant suggestion — we can proxy it by the increase in the number of enrollments in institutions of higher learning. Why should it work? Well, four decades ago another brilliant historical sociologist, Randall Collins, published an important, but largely ignored book, The Credential Society, in which he argued that most youngsters go to college not to expand their minds, but to simply obtain a piece of paper (the diploma) that improves their chances of getting a lucrative job (shame about it). Thus, when competition for elite positions intensifies, more people seek to obtain advanced degrees.

In his study of the seventeenth century crisis in England, Goldstone looked at enrollments at such universities as Oxford and Cambridge. He found that indeed, the enrollments at Oxford, for example, ballooned during the first half of the seventeenth century, in the period preceding the English Civil War. And it wasn’t just a long-term modernization trend in which people came to value education more. When intraelite competition subsided in the early eighteenth century, so did Oxford enrollments. I am not saying that everybody who went to Oxford just wanted to get the credentials, rather than education. But those who were really interested in knowledge were a decided minority.

Of course we have to be careful. Many factors can affect the number of youth seeking higher education, not only increased competition for high-quality jobs. So we should seek other proxies for the quantity of interest, and check whether they tell the same story. For seventeenth century’s England, we can also look to such proxies of competition as the amount of litigation. Another one that I used for both England and France was the frequency of dueling. It turns out that dueling epidemics tend to develop during periods of high intraelite competition. Makes sense.

At least we don’t have much of a dueling problem…

The Lindy effect

Saturday, March 23rd, 2013

The Lindy effect sounds like a short-lived fad from the 1930s, when really it describes such fads — or, rather, their lifetimes:

The longer a technology has been around, the longer it’s likely to stay around. This is a consequence of the Lindy effect. Nassim Taleb describes this effect in Antifragile but doesn’t provide much mathematical detail. Here I’ll fill in some detail.

Taleb, following Mandelbrot, says that the lifetimes of intellectual artifacts follow a power law distribution. So assume the survival time of a particular technology is a random variable X with a Pareto distribution. That is, X has a probability density of the form

f(t) = c/tc+1

for t ? 1 and for some c > 0. This is called a power law because the density is proportional to a power of t.

If c > 1, the expected value of X exists and equals c/(c-1). The conditional expectation of X given that X has survived for at least time k is ck/(c-1). This says that the expected additional life X is ck/(c-1) – k = k/(c-1), and so the expected additional life of X is proportional to the amount of life seen so far. The proportionality constant 1/(c-1) depends on the power c that controls the thickness of the tails. The closer c is to 1, the longer the tail and the larger the proportionality constant. If c = 2, the proportionality constant is 1. That is, the expected additional life equals the life seen so far.

Note that this derivation computed E( X | X > k ), i.e. it only conditions on knowing that X > k. If you have additional information, such as evidence that a technology is in decline, then you need to condition on that information. But if all you know is that a technology has survived a certain amount of time, you can estimate that it will survive about that much longer.

This says that technologies have different survival patterns than people or atoms. The older a person is, the fewer expected years he has left. That is because human lifetimes follow thin-tailed distributions. Atomic decay follows a medium-tailed exponential distribution. The expected additional time to decay is independent of how long an atom has been around. But for technologies follow a thick-tailed distribution.

Another way to look at this is to say that human survival times have an increasing hazard function and atoms have a constant hazard function. The hazard function for a Pareto distribution is c/t and so decreases with time.

The effect applies to many creative artifacts:

The previous post looked at technologies, but the Lindy effect would apply, for example, to books, music, or movies. This suggests the future will be something like a mirror of the present. People have listened to Beethoven for two centuries, the Beatles for about four decades, and Beyoncé for about a decade. So we might expect Beyoncé to fade into obscurity a decade from now, the Beatles four decades from now, and Beethoven a couple centuries from now.

This is in contrast to things that break down:

If you look at a 25 year-old car and a 3 year-old car, you expect the latter to be around longer. The same is true for a 25 year-old accountant and a 3 year-old toddler.