Science

…cetacean brain size, relative to body size, increased substantially about thirty-eight mill years ago when the odontocetes evolved from the ancient archaeocetes…

What drove these changes? It does not seem to have been the transition to an aquatic existence itself as that occurred about fifty-five million years ago and brains stayed at roughly the same relatively small size relative to body weigt as the archaeocetes made their gradual entry into the ocean.  A better hypothesis is that the increased brain size of the odontocetes thirty-eight million years ago was driven by the evolution of echolocation.  The early odontocetes had inner ear bones that were good at picking up high frequency sound, which suggests that they had developed a form of sonar.  Lori Marino thinks “that echolocation came on line and then got co-opted for social communicative purposes.”  In this scenario, the odontocete brains increased in relative size to deal with the acoustic information itself, as well as, perhaps, a new perceptual system based on the data from the returning echoes.  But…the change may have been even more profound: “This may indicate that the large brains of early odontocetes were used, at least partly, for processing this entirely new sensory mode [echolocation] that evolved at the same time as these anatomical changes and perhaps for integrating this new mode into an increasingly complex behavioral ecological system.”

That is from the new and notable The Cultural Lives of Whales and Dolphins, by Hal Whitehead and Luke Rendell, previously covered on MR here.  And here is my earlier post on the economics of dolphins.

Human-dolphin fishing cooperatives

by on November 21, 2014 at 2:37 am in Books, Education, Science | Permalink

1. They have been reported to exist in Australia, India, Mauritania, Burma, and the Mediterranean, but the best known are in Brazil.

2. In parts of southern Brazil, human fisherman have been cooperating with dolphins for many generations (of each species).

3. If fishermen clap just the right way, dolphins will herd fish into the desired areas of fishermen, in muddy lagoon areas.

4. The dolphins perform a distinctive kind of dive to signal to the humans it is time to cast the net for the fish.

5. Only some individual dolphins are able (willing?) to do this well, perhaps the others belong to the forty-seven percent.

5b. The dolphins which cooperate with the fisherman are also more social, more socially connected, and more cooperative with other dolphins.

6. The Brazilian fishermen name the star cooperating dolphins after ex-presidents, soccer players, and Hollywood stars.

7. The names aside, it is not clear whether dolphins benefit from offering this assistance; some commentators suggest the dolphins end up with isolated or injured fish from these exercises.

Here is one blog post report on these practices.  Here is one piece of the original research.  I stumbled upon this while reading the new and excellent Hal Whitehead and Luke Rendell The Cultural Lives of Whales and Dolphins, a new book from University of Chicago Press.

We have some new results, from Maria Victoria Anauati, Sebastian Galiani, and Ramiro H. Gálvez, all consistent with my prior intuitions:

Does the life cycle of economic papers differ across fields of economic research? By constructing and analyzing a large dataset that combines information on 9,672 articles published in the top five economic journals from 1970 to 2000 with detailed yearly citation data obtained from Google Scholar, we find that published articles do have a life cycle that differs across fields of economic research (which we divide into the categories of applied research, applied theory, econometrics methods and theory). Applied research and applied theory papers are the clear winners in terms of citation counts. For the first years after their publication, they receive higher numbers of citations per year than papers in other fields of research do. They also reach a higher peak number of citations per year and apparently sustain those peak levels for longer, in addition to being cited over longer periods of time (i.e., they have a longer lifespan). Citation patterns are much less favorable for theoretical papers, which are the object of fewer citations per annum in the first years following publication, have lower peak numbers and a shorter lifespan. Econometric method papers are a special case; the pattern for most of these papers is similar to the pattern for theory papers, but the most successful papers (as measured by the number of citations) on econometric methods are also the most successful papers in the entire discipline of economics.

The SSRN paper is here.  And via Ben Southwood, here is an interesting new paper on how citation success usually pops up early in the life of a paper: “…citations in the first two years after publication explain more than half of the variation in cumulative citations received over a longer period.”

No one knows for sure, you will find a brief survey of some estimates here.  Let’s start with a few simpler points, however.

First, China is notorious for making announcements about air pollution and then not implementing them.  This is only partially a matter of lying, in part the government literally does not have the ability to keep its word.  They have a great deal of coal capacity coming on-line and they can’t just turn that switch off.  They’re also driving more cars, too.

Second, China falsifies estimates of the current level of air pollution, so as to make it look like the problem is improving when it is not.  Worse yet, during the APEC summit the Chinese government blocked the more or less correct estimates coming from U.S. Embassy data, which are usually transmitted through an app.  A nice first step to the “deal” with the United States would have been to allow publication (through the app) of the correct numbers.  But they didn’t.  What does that say about what one might call…”the monitoring end”…of this new deal?

Third, a lot of the relevant Chinese regulatory apparatus is at the local not federal level (in fact it should be more centrally done, even if not fully federalized in every case).  There are plenty of current local laws against air pollution which are simply not enforced, often because of corruption, and often that pollution is emanating from locally well-connected, job-creating state-owned enterprises.  Often the pollution comes from one locality and victimizes another, especially in the north of the country.   Those are not good local regulatory incentives and it will take a long time to correct them.  Right now for instance Beijing imports a lot of its pollution from nearby, poorer regions which simply wish to keep churning the stuff out.  The Chinese also do not have anything close to a consistently well-staffed environmental bureaucracy.

Fourth, if you look at the history of air pollution, countries clean up the most visible and also the most domestically dangerous problems first, and often decades before solving the tougher issues.  For China that highly visible, deadly pollutant would be Total Particulate Matter, which kills people in a rather direct way, and in large numbers, and is also relatively easy to take care of.  (Mexico for instance has been getting that one under control for some time now.)  The Chinese people (and government) are much more worried about TPM than about carbon emissions, which is seen as something foreigners complain about.  Yet TPM is still getting worse in China, and if it is (possibly) flat-lining this year that is only because of the economic slowdown, not because of better policy.

When will China cap carbon emissions?  “Fix TPM and get back to me in twenty years” is still probably an underestimate.  Don’t forget that by best estimates CO2 emissions were up last year in China by more than four percent.  How many wealthier countries have made real progress on carbon emissions?  Even Denmark has simply flattened them out, not pulled them back.

The Chinese really are making a big and genuine effort when it comes to renewables, it is just that such an effort is dwarfed by the problems mentioned above.

The media coverage I have seen of the U.S.-China emissions “deal” has not been exactly forthcoming in presenting these rather basic points.  It’s almost as if no one studies the history of air pollution anymore.

I understand why a lot of reporters want to “clutch at straws” — it’s good for both clicks and the conscience — but a dose of realism is required as well.  The announced deal is little more than a well-timed, well-orchestrated press release.

It’s well known that GDP per capita increases with distance from the equator and it does so moving both North and South. (I discuss this correlation at MRU in Geography and Development, Disease (video)). Dietz Vollrathat at the Growth and Development Blog points us to a new paper by Holger Strulik and Carl-Johan Dalgaard that shows that development used to be greater nearer the equator. Here’s the big picture.

The top panel shows that as absolute latitude (distance from the equator) increases today so does development, here measured as the urbanization rate. The left panel shows the world. The right panel shows, rather remarkably, that the relationship continues to hold in Europe.  The bottom panel shows that as absolute latitude increased in 1500 development, here measured as population density, decreased both in the world and Europe.

LatitudeIncome

What can account for this relationship and its reversal? The authors have a let’s say highly speculative (but very interesting!) theory. It runs as follows. Animals and people get bigger in colder climates possibly because surface area to volume decreases with size so larger animals can retain heat more easily. All else the same, however, bigger people means fewer people and so in the pre-industrial era higher latitudes had smaller populations leading to less innovation (ala my TED talk on market size and innovation). But fewer children also meant more investment in human capital per child (a Beckerian quality-quantity tradeoff). Higher human capital per child leads to increases in technology which allow and encourage even more human capital accumulation and fewer but yet even higher quality children and thus you hit a takeoff point where the economies of the colder regions accelerate generating the modern relationship.

Phew! Now that’s a theory. I don’t say that I believe it but I applaud the ambition. Bravo!

What alternative theories do MR readers propose?

In the modern sense that is, of course potatoes have been genetically modified for a long time:

The Agriculture Department on Friday approved the first genetically modified potato for commercial planting in the United States, a move likely to draw the ire of groups opposed to artificial manipulation of foods.

The Innate potato, developed by the J.R. Simplot Co., is engineered to contain less of a suspected human carcinogen that occurs when a conventional potato is fried, and is also less prone to bruising during transport.

Boise, Idaho-based Simplot is a major supplier of frozen french fries to fast-food giant McDonald’s.

The story is here, and you will note that on Tuesday the mandatory GMO-labeling initiatives failed in Oregon and Colorado, the second failure in Oregon and that means failures in four states overall.  Less positively, voters in Maui County, Hawaii chose to restrict GMO cultivation altogether.  And now McDonald’s is under pressure not to use these new potatoes for its french fries.  But of course you can understand the marketing dilemma of McDonald’s here — they can’t just come out and say “these french fries won’t give you cancer.”

Andrea Matranga has a job market paper (pdf) which is speculative but interesting:

During the Neolithic Revolution, seven populations independently invented agriculture. In this paper, I argue that this innovation was a response to a large increase in climactic seasonality. Hunter-gathers in the most affected regions became sedentary in order to store food and smooth their consumption. I present a model capturing the key incentives for adopting agriculture, and I test the resulting predictions against a global panel dataset of climate conditions and Neolithic adoption dates. I find that invention and adoption were both systematically more likely in places with higher seasonality. The findings of this paper imply that seasonality patterns 10,000 years ago were amongst the major determinants of the present day global distribution of crop productivities, ethnic groups, cultural traditions, and political institutions.

Here is his home page.

Telepathy over the Internet

by on November 7, 2014 at 7:22 am in Science | Permalink

A amazing paper in PLOS One demonstrating a kind of telepathy over the internet:

…two participants had to carry out a specific task in the form of a series of consecutive trials of a computer game. The game was designed so that the two participants had to play cooperatively, and the required cooperation could only be achieved through direct brain-to-brain communication. The goal of the game was to mind melddefend a city from enemy rockets fired by a pirate ship… One participant was able to see the game on a computer screen, but was not provided with any input device to control the cannon. The second participant could use his/her right hand to press a touchpad, but could not see the game. The two participants were located in separate buildings on the University of Washington’s campus. Specifically, the Sender side was stationed in the Computer Science & Engineering building while the Receiver side was stationed in the Psychology building. The two buildings were located approximately 1 mile apart. The two participants could only communicate with each other through a brain-to-brain communication channel.

During rocket trials, the sender conveyed the intent to fire the cannon by engaging in right hand motor imagery. Electrical brain activity from the Sender was recorded using EEG, and the resultant signal was used to control the vertical movement of a cursor – this allowed the subject to get continuous feedback about imagery performance. When the cursor hit the “Fire” target (a large blue circle) located at the top of the screen, the Sender’s computer transmitted a signal over the Internet to the Receiver’s computer. The two computers communicated using the standard hypertext transfer protocol (HTTP).

The Receiver’s computer was connected through a custom-made serial cable to a TMS machine. Whenever the Receiver’s computer received a fire command, a TMS pulse was delivered to a pre-selected region of the Receiver’s brain. The stimulation caused a quick upward jerk of the Receiver’s right hand, which was positioned above the touchpad. This up-down movement of the hand typically resulted in enough force to trigger a “click” event on the touchpad, causing the cannon in the computer game to be fired as requested by the Sender.

The players were able to perform significantly better than chance at firing the cannon and saving the city.

The content of the communication is obviously low–basically 1 bit–but the author’s offer some intriguing speculation. Language is a significant limit on communication. In Polanyi’s terms we know more than we can say; a lot of knowledge is tacit. But can we say what we know with telepathy?

…current methods for communicating are still limited by the words and symbols available to the sender and understood by the receiver….A great deal of the information that is available to our brain is not introspectively available to our consciousness, and thus cannot be voluntarily put in linguistic form. For instance, knowledge about one’s own fine motor control is completely opaque to the subject, and thus cannot be verbalized. As a consequence, a trained surgeon or a skilled violinist cannot simply “tell” a novice how to exactly position and move the fingers during the execution of critical hand movements….Can information that is available in the brain be transferred directly in the form of the neural code, bypassing language altogether? We explore this idea in the rest of this article….

We have a long way to go on that score. The authors haven’t transferred thought or the pattern of thought but rather have used a kind of intermediary language, namely the computer interpretation of the brain signal. Still, credit the authors with vision.

Oh, and if that isn’t enough to blow your mind, another group has demonstrated human to animal telepathy.

A terrified window cleaner was rescued by a high-tech drone after the scaffolding he was on malfunctioned.

The man was cleaning windows close to the top of a high rise building in central Abu Dhabi, in the United Arab Emirates, when the motorised scaffold stopped working and started tilting dangerously.

The Security Media Department sent a wireless remote-controlled drone to rescue the cleaner amid dramatic scenes yesterday.

From the Daily Mail, there is more here, via the excellent Mark Thorson.

Because they sound mighty interesting:

Bousso is not interested in what goes on outside the causal diamond, where infinitely variable, endlessly recursive events are unknowable, in the same way that information about what goes on outside a black hole cannot be accessed by the poor soul trapped inside. If one accepts that the finite diamond, “being all anyone can ever measure, is also all there is,” Bousso said, “then there is indeed no longer a measure problem.”

In 2006, Bousso realized that his causal-diamond measure lent itself to an evenhanded way of predicting the expected value of the cosmological constant. Causal diamonds with smaller values of Λ would produce more entropy — a quantity related to disorder, or degradation of energy — and Bousso postulated that entropy could serve as a proxy for complexity and thus for the presence of observers. Unlike other ways of counting observers, entropy can be calculated using trusted thermodynamic equations. With this approach, Bousso said, “comparing universes is no more exotic than comparing pools of water to roomfuls of air.”

The article, by Natalie Wolchover and Peter Byrne, is interesting throughout.  I do sort of understand this sentence:

But as attempts to paint our universe as an inevitable, self-contained structure falter, the multiverse camp is growing.

The pointer is from the esteemed David Levey.

That is the conclusion from Alex Verstak et.al., here are some sentences to ponder:

…the impact of older articles has grown substantially over 1990-2013. In 2013, 36% of citations were to articles that are at least 10 years old; this fraction has grown 28% since 1990. The fraction of older citations increased over 1990-2013 for 7 out of 9 broad areas and 231 out of 261 subject categories. Second, the increase over the second half (2002-2013) was double the increase in the first half (1990-2001).

The full abstract and article is here.  For the pointer I thank Dan Getz.

A Rare (Earth) Case of Wisdom

by on November 4, 2014 at 7:22 am in Economics, History, Science | Permalink

Four years ago we were being warned that China’s monopoly on rare earths was a threat to the United States. Since rare earths are key resources for both national defense and green technology, the crisis united right and left in fear and anger.

Paul Krugman titled his column Rare and Foolish and he was hardly alone when he wrote:

You really have to wonder why nobody raised an alarm while this was happening, if only on national security grounds. But policy makers simply stood by as the U.S. rare earth industry shut down….The result was a monopoly position exceeding the wildest dreams of Middle Eastern oil-fueled tyrants.

…, the affair highlights the fecklessness of U.S. policy makers, who did nothing while an unreliable regime acquired a stranglehold on key materials.

Yet you probably haven’t heard much about this crisis recently. Why not? Ans: The crisis was exaggerated and what wasn’t exaggerated the market alleviated. Eugene Gholz of CFR has a balanced examination of what happened. I summarize:

  • The Chinese government might or might not have wanted to take advantage of their temporary monopoly power (it’s still unclear what the fishing incident was all about) but Chinese producers did a lot to evade export bans both legally and illegally.
  • Firms that had been using rare earths when they were cheap decided they didn’t really need them when they were expensive.
  • New suppliers came on line as prices rose.
  • Innovations created substitutes and ways to get more from using less.

Even the government did some good by funding competitions to support basic and applied research in substitute products and processes. Gholz draws a simple lesson:

…policymakers should not succumb to pressure to act too quickly or too expansively in the face of raw materials threats.

I agree but would add that at the time it was almost surreal how quickly nominal free traders and internationalists merged into war hawks. We did surprisingly well to not overreact politically and instead let market forces solve the problem. A disruption in our trade partnership with China would have been far more dangerous to our national security than a dispute over rare earths. I’d say that’s a rare earth case of wisdom.

Addendum: Bonus points to Tim Worstall, economist blogger and rare earth dealer, who in 2010 at the height of the crisis pointed out that rare earths were neither rare nor earths and China’s monopoly had been won only by low prices that accrued to our benefit. “If Beijing wants to raise its prices and start using supplies as geopolitical bargaining chips,” he wrote, “so what? The rest of the world will simply roll up its sleeves and ramp up production, and the monopoly will be broken.” Nailed it.

Here is the new paper by Michael Reay in Social Forces:

Analyses of the multiple cognitive structures and social effects of humor seldom look at why these tend to center on particular topics. The puzzle of how humor can be highly varied yet somehow constrained by its source “material” is explored using a corpus of over 600 incidents, not of deliberate jokes, but of the “wilder,” unplanned laughter that occurred during a set of interviews with economists—professionals who at the time (1999–2000) enjoyed an unprecedented degree of status and influence. The analysis finds that the source material for this laughter typically involved three kinds of socially structured contradiction: between ideals and reality, between different socially situated viewpoints, and between experiences occurring at different times. This illustrates how particular kinds of content can have a special laughter-inducing potential, and it suggests that wild laughter may at root be an interactional mechanism for dealing with social incongruity—even for members of relatively powerful groups. It is argued that this could not only help solve the larger puzzle of simultaneous variety and constraint in deliberate comedy, but also explain why the characteristic structures of humor are associated with a particular range of social effects in the first place.

Reading that abstract caused me to engage in some unplanned (silent) laughter.

For the pointer I thank the excellent Kevin Lewis.

Ten years ago when Burt Rutan was predicting 100,000 space tourists in ten years I wrote a widely debated article, Is Space Tourism Ready for Takeoff? My answer then, and my answer now, is no:

The vision is enticing but the facts suggest that space tourism is not ready for market. The problem is not the monetary expense, there are enough millionaires with a yearning for adventure to support an industry. The problem is safety. Simply put, rockets remain among the least safe means of transportation ever invented. Since 1980 the United States has launched some 440 orbital launch rockets (not including the Space Shuttle). Nearly five percent of those rockets have experienced total failure, either blowing up or wandering so far from course as to be useless. The space shuttle has a slightly better record of safety — it was destroyed in two of 113 flights. There are lots of millionaires willing to spend one or two million dollars for a flight into space but how many will risk a two to five percent chance of death?

It is true that we have been “learning by doing” or in this case by learning by exploding. In the 1960s the risk of failure was a stunning 12%. As in other industries, learning by doing reduced the failure rate dramatically over the first units but more slowly thereafter. In the 1970s the failure rate dropped to 5.2% but nearly thirty years later the failure rate for rockets still hovers between four and five percent. We can expect similar slow and steady improvements in the future but there is little reason to expect dramatic improvements in rocket technology

Unfortunately with two disasters this week, one of them sadly involving the loss of life, the safety of rockets continues to be far too low to support significant tourism. Virgin Galactic’s VSS Enterprise, which crashed yesterday, was just on its 23rd powered flight suggesting a failure rate of perhaps 5%, in line with expected values. An earlier tragedy involving tests of the rocket motor killed 3 people.

As I said ten years ago, even a failure rate of 1 in 10,000 is far too high to support space tourism of the “fat guys with camera” variety and we are not yet close to a failure rate of 1 in 10,000.

Good sentences

by on October 29, 2014 at 3:25 pm in Economics, History, Science | Permalink

To develop an intuition for our main result, note that the equilibrium private saving behavior must be resistant to rare mutants.

That is from the new Robson and Szentes AER paper, “Biology and Social Discounting,” which argues that the nature of sexual reproduction causes private discount rates to rise above social ones.