Wednesday, March 9th, 2016

Time	Event
12:00a	Trading places Tennessee has abundant hardwood forests, and business sectors related to them thrived for many years. Yet the state’s employment levels in the flooring, furniture-making, and cabinetry industries have cratered — down by 72 percent, 50 percent, and 50 percent, respectively, from 2005 to 2009. What happened? The economic slump in the U.S. certainly hurt those trades. But also: China happened. As some economists now recognize, the formal trade relationship between the U.S. and China, established in the 1990s and solidified with a World Trade Organization agreement in 2001, dramatically affected a large number of labor-intensive industries in the U.S. In those fields, jobs moved en masse to China, where workers are available at even lower wages. That relatively sudden shift, research has shown, comes with a heavy cost to U.S. workers. When jobs vanish, the better-trained workers may bounce back, but many blue-collar workers do not. And entire communities have been punished economically as well. These findings run against the bullish assumptions many economists have made about international trade in recent decades. But now a paper co-authored by MIT economist David Autor analyzes the data and makes clear how significant that impact has been. “Among the most skilled workers, we’ve seen lots of [job] reallocation without any dire consequences,” says Autor. “But for the lower-skilled [workers], we just see more scarring. Their wages fall regardless of what they’re doing. They’re just on a permanently lower trajectory.” Consider: From 1999 through 2011, as the new work by Autor and his colleagues shows, import growth from China cost the U.S. about 2.4 million jobs. In turn, about 985,000 of those were in manufacturing — a large portion of the 5.8 million manufacturing jobs that the U.S. lost in total in that time. Of course, as Autor notes, trade also creates employment. For instance, he observes, it is hard to conceive of Apple’s monumental growth without the firm using China as its workshop. But evidence that the U.S. has experienced large job gains that counter the employment losses in sectors that compete with imports has been decidedly elusive so far. The net impact on workers in U.S. regions heavily affected by competition from China has been particularly serious. Autor and his colleagues have evaluated the direct impact of low-wage Chinese industry on incomes in the more than 700 Commuting Zones (CZs), or urban areas, in the U.S. Comparing workers in CZs at the 75th percentile of exposure to Chinese competition (those strongly affected) with workers in CZs at the 25th percentile, they see a reduction in annual income of $549 per adult, while per-capita income from federal assistance only rises by $58. All told, the paper states, “international trade tends to make low-skilled workers in the U.S. worse off — not just temporarily, but on a sustained basis.” The paper, “The China Shock: Learning from Labor Market Adjustment to Large Changes in Trade,” will be published in the Annual Review of Economics. The co-authors are Autor; David Dorn of the University of Zurich in Switzerland, and Gordon Hanson of the University of California at San Diego. Tennessee vs. Alabama The idea that global trade benefits all countries has been inscribed into economic literature for decades — or centuries, even, dating back to David Ricardo in the early 1800s and Adam Smith in the 1770s. It was also reinforced by the relatively minor effects international trade appeared to have in the first decades after World War II, under terms settled at the Bretton Woods agreement of 1944. “I think that a lot of people’s priors, or expectations, had come from the Bretton Woods era of trade,” Autor says. “A lot of that was rich country-to-rich country trade: We buy cheese from France and we sell them aircraft engines.” But more recently, Autor points out, China has functioned as “a new low-cost producer of labor-intensive goods, and everything that’s labor-intensive we’re no longer competitive in. It’s just going to shut down. That’s probably why [global trade] was so much more disruptive than people had anticipated.” After all, mainstream economics has held that the benefits of trade — mostly lower prices on imported goods — should compensate for disappearing jobs, on aggregate. But the current data shows how unevenly distributed those benefits and costs are. “It certainly is the case that trade contributes to certain lower-priced goods and services, and on the average, that lowers the cost of living,” Autor notes. “But for displaced workers, the fact that things are 10 percent cheaper at Walmart is just not making up for the fact that they’re not employed.” Autor adds: “Trade should increase GDP on aggregate, but it’s going to produce winners and losers.” For instance: Alabama, which neighbors Tennessee to the south, also has considerable manufacturing. But little of it involves industries in which China has invested. So while at least half of Tennessee is in the highest quartile of areas exposed to Chinese competition, only a couple of patches of Alabama are in the same category. “Tennessee, owing largely to its concentration of furniture producers, is far more exposed to trade with China than is Alabama, which has agglomerations of relatively heavy industry,” the paper states. Robert Feenstra, an economist at the University of California at Davis, says the research has advanced the state of knowledge among trade and labor economists. ‘They have very good data,” Feenstra says. “They just got bigger numbers than anybody thought,” in terms of the impact of trade with China on the U.S. job market. Feenstra suggests that continuing research will be needed to assess the complete impact of trade policy agreements on the U.S., including additional study “on the export side,” that is, the extent to which trade deals have opened up new manufacturing opportunities for U.S. firms that are exporting goods. The new research agenda To be sure, as free-trade advocates like to point out, international agreements have also improved conditions for workers in the developing world. Chinese wages have risen dramatically and the country’s share of world manufacturing value added has risen from about 4 percent in 1991 to 24 percent in 2012. Still, concerned policymakers in the U.S. are left wondering what kinds of programs, from trade adjustment assistance to job retraining and more, can help workers in their own country. And as Autor notes, the general acceptance of trade’s value means that “trade adjustment policy has been a total orphan policy for a long time.” So Autor’s current work on trade has two practical aspects. He is trying to spread the recent empirical findings around academia, while undertaking studies that dive into the broader social effects of trade, beyond employment outcomes. Among his ongoing studies are one examining the effects of trade shocks on political polarization; another looking at the effects of trade on earnings and research and development investment among U.S. companies; and a third that looks at underemployment, family structure, and the disintegration of two-parent households. “Work is really wrapped up with identity,” Autor observes. “Work is not just money for most people. They don’t fare as well when they don’t feel they have a meaningful thing to apply themselves to.” All of this research, Autor adds, is meant to speak to interested policymakers and reinforce the idea that trade policy is not just an issue that stands apart from larger issues concerning the social fabric of America. “If we’re now in the era where we’re going to say we now recognize that trade has very strong disruptive effects,” Autor says, “then what do we do about it? What is the right policy?” (Comment on this)
12:30p	Wristband detects and alerts for seizures, monitors stress People with epilepsy suffer from recurrent, unprovoked seizures that can cause injury and even death from “sudden unexpected death in epilepsy” (SUDEP), a condition that occurs minutes after a seizure ends. Now Empatica, co-founded by MIT professor and wearables pioneer Rosalind Picard, has developed a medical-quality consumer wristband, called Embrace, that monitors stress signals to detect potentially deadly seizures and alert wearers and caregivers, so they can intervene. Researchers worldwide are using a scientific version of the wristband, called the E4, which also measures other signals, to study epilepsy and other neurological and psychiatric conditions. Numerous academic papers are now published, showing that the combined electrodermal activity (EDA), also known as skin conductance, and motion data collected from the wrist improve the accuracy of seizure detection over using only motion data. Now Empatica is prepping to release Embrace, “a consumer-looking, but medical-quality device” for monitoring stress and seizures, says Picard, a professor of media arts and sciences in the MIT Media Lab and Empatica’s chief scientist. After a successful Indiegogo campaign last year, the beta version of Embrace shipped to backers last Friday. Apart from detecting seizures, anyone can also use the wristbands to monitor stress levels — which is important for good health, Picard says. Chronic stress has been linked to numerous health issues such as heart disease, obesity, and diabetes. “Stress signals reach every organ of your body, so these stress signals are potentially influencing everything,” Picard says. “Sometimes you don’t realize [you’re stressed] until you get that just-in-time notice.” Better stress detection for all According to the World Health Organization, roughly 50 million people worldwide suffer from epilepsy. The Centers for Disease Control and Prevention estimates about one in every 1,000 people with epilepsy die annually from SUDEP, a possible result of suffocation from impaired breathing, fluid in the lungs, or seizing while sleeping face down. Rates are significantly higher for people who have had at least one grand mal seizure — one of the most dangerous types of seizures — in the past year, Picard says. With Embrace, Empatica aims to aid people suffering from epilepsy by helping them better alert loved ones, Picard says. An app that comes with Embrace lets wearers and others monitor when the person might be having a grand mal seizure. The wristbands resemble watches but have a solid silver or black face. Sensors underneath the face track pulse, body motion, temperature, and EDA, which involves subtle electrical changes across the skin. Boosts in EDA, without accompanying changes in motion, can signal stress. In people with epilepsy, a sharp rise in both signals could indicate a severe, potentially life-threatening seizure. When the wristband detects a seizure, it vibrates, and the wearer can respond. If the wearer becomes unconscious, which happens with the most dangerous seizures, and doesn’t respond quickly, the app sends an alert to a designated individual. “If somebody goes to check on a person during or after they have had a grand mal seizure, then they are less likely to die,” Picard says. “In some cases, simply saying the person’s name or turning them over (gentle stimulation) might save their life. Anybody could do this potentially life-saving action, they just need to know to go check on the person — don’t leave them alone right after a seizure.” Additionally, teachers and parents may want to monitor the stress levels of a child with emotion regulation issues or autism. The device may determine, for instance, if a child is experiencing a “fight-or-flight response,” and can be set to vibrate to alert parents or teachers. “You can see if the child lying on the floor or on the ground in the playground might be about to have a meltdown … even though they may look calm outwardly,” she says. “Several teens with autism told us they often can’t tell they’re about to explode until it’s too late. Maybe this could help some of them get an alert while they’re still in control.” For epilepsy researchers, Picard says, the E4 wristband has made it possible to gather real-time data from patients going about their daily lives. Empatica’s website now lists around 20 academic papers that use E4 in studies on subjects ranging from autism to resuscitation after a heart attack. In 2012, Picard and researchers published a paper in Neurology that correlated greater responses on the wrist with longer suppression of brain waves on the scalp. This meant certain regions of the brain were experiencing hyperactivity while the cortex, which is near the scalp, was shutting down — a phenomenon observed in all SUDEP cases. (This has now become an important biomarker for SUDEP.) Other results have identified a critical window when someone may stop breathing after having a seizure. And, in a 2014 study published in the journal Epilepsy and Behavior, researchers using the device found that teaching people to control their skin conductance helps reduce seizures by 49 percent in adults that suffer from a type of epilepsy triggered by stress. Importantly for research, Picard says, the device specifically detects stress signals from the sympathetic response of the autonomic nervous system, which is commonly associated with the fight-or-flight responses indicative of stress and seizures. “When we measure the skin response, we are seeing signals that originate deep in the brain, from regions so far under the scalp that a traditional EEG cannot pick them up,” Picard says. In that way, the E4 is also valuable in studying other neurological conditions such as autism, anxiety, depression, phobias, and post-traumatic stress disorder (PTSD), Picard adds. “A PTSD researcher, for instance, may use the device to more accurately study why and how a patient may experience heightened flight-or-fight responses,” she says. Staying in the medical space Empatica’s core technology traces back to 2007, when Picard and researchers developed iCalm, a similar EDA-measuring wristband. In 2009, Picard and former postdoc Rana el Kaliouby co-founded Affectiva to commercialize the wearable device, then called the Q Sensor, to be used for measuring stress associated with autism. Then one day when a student borrowed two Q Sensor wristbands to monitor the stress levels of his little brother with autism. He put one wristband on each wrist. When Picard checked the data remotely from her computer, she noticed “a whopper of a response on one side and nothing on the other,” she says. “It was such a big response, I didn’t believe it was real.” Nothing she did in her lab could reproduce such a response. However, the student had kept a diary and, sure enough, on the exact date and time of the “whopper” response, the brother had had a seizure. As it turns out, minutes before someone has a seizure, the hair on one arm may stand on end. But Affectiva soon changed course and began developing software that monitored and quantified people’s emotions for market research. So Picard founded another startup, Physiio, “to help the technology grow in the medical space,” Picard says. This caught the attention of a small, Italian, stress-tracking-wearable startup co-founded by Matteo Lai and Simone Tognetti. In 2011, the two companies merged to form Empatica, with Lai as CEO and Tognetti as chief technology officer. Since then, Empatica has produced several iterations of the E4 for clinical use, with the most recent version released last year. But now the startup is “laser-focused” on bringing the Embrace to consumers, Picard says. So does Picard — the consumer — use her own device? Yes, and she says the wristband has revealed interesting things about her own life. “The first time I wore this, I’m driving home and it’s going off, and I think, ‘I guess I’m letting myself get a little bent out of shape here,’” Picard says. “I’ve found it fabulous to learn about what’s going on with myself.” (Comment on this)
1:30p	Q&A: John Hansman on the first global standards for aircraft emissions Last month, the United States and 22 other countries agreed to the first-ever global carbon emissions standards for commercial aircraft. The standards, set by the United Nations’ International Civil Aviation Organization (ICAO), are estimated to reduce carbon emissions by more than 650 million tons between 2020 and 2040 — roughly equal to the emissions produced by 140 million cars in a single year. The standards will apply to all new aircraft designs launched after 2020 and will be phased in for existing aircraft models launched after 2023. John Hansman, professor of aeronautics and astronautics at MIT, led the MIT technical analysis that contributed to setting the standard. MIT News spoke with Hansman about MIT’s role in the international negotiations and whether a less polluting fleet will look much different from today’s aircraft designs. Q: What technological and regulatory changes will have to be made in order to meet these aircraft emissions standards? A: If (the standard) is adapted, basically new airplanes in the future will have to be at the state of the art of fuel efficiency. What that means is, the engines and the aerodynamics of the airplanes will have to be efficient, and the targets for efficiency will vary depending on the size or weight of the airplane: more aggressive for larger airplanes that fly longer distances — those would be Boeings, Airbus, et cetera — not as tight for small corporate jet airplanes. Because fuel, particularly in the past few years, has been expensive, aircraft manufacturers have already been trying to make their planes as efficient as possible. This means the current airplanes that are the most efficient, like the Boeing 787 and the Airbus A350, will not change — they already meet the standard. But airplanes we’ve been producing for a long time, that are older designs, would have to be upgraded. So [the standard] puts a limit on how long those airplanes will be able to be produced before you have to modernize the design. The airplanes will not look that different from the outside. Most of the changes are subtle and have to do with the engines, like the size of the fan in the engines, internal parts of the engine, the weight of the components, and the aerodynamics. You might see some external shape changes such as winglets, but many aircraft have already incorporated them for efficiency improvements. Q: Does the technology exist today to meet these standards? A: Yes. When you determine standards like this, there’s always a tension, which is, you’d like to make them as aggressive as possible. But if you make them unrealistically tough, people can’t [meet the standard]. So part of the analysis is to determine what’s feasible. When the standards were being evaluated, you couldn’t assume magic changes in technology. You tend to use the best demonstrated or available technology and aircraft as the existence proof for what you can get. It’s possible that 10 or 20 years from now there will be new technologies. In fact we’re working on some, like the D8, Double Bubble [aircraft], which would be an improvement in efficiency well past what this standard would require. But at this point, the D8 is considered an unproven technology. What we’re really doing is bringing everybody up to the level of technology that we know we can meet. There’s sort of a sweet spot of pushing the technology enough, but not pushing it so far that people are disincentivized to actually create new designs. Q: What was MIT’s role within this international process? A: About eight years ago, there was a subcommittee set up within the ICAO’s Committee on Aviation Environmental Protection to look at this with members from around the world. We were asked as part of the FAA’s Center of Excellence to come on this team to help do technical analysis and modeling of how good the technologies could be, how much improvement you could get, and what the impact would be on certain aircraft designs. The first phase was to come up with the right metric. We were interested in CO2, but the amount of CO2 you generate is proportional to the amount of fuel you burn. So the ultimate metric became an equivalent to the miles per gallon you’d have for a car, and it’s called the Specific Air Range, versus the takeoff weight of the airplane. It was recognized that for higher takeoff weights, you’d have higher performance requirements. Once the metric was agreed upon, it was then necessary to determine what the target levels would be — basically, what mile-per-gallon performance would be required to certify an aircraft. This will force some aircraft to have to be redesigned. As you can imagine, your view of where to draw the line depends on what country you are and what manufacturers are within your country. Within MIT, we had worked on developing tools that could model both environmental and cost impacts of policy changes. One is the Aircraft Environmental Design Tool. What it does is to model all the aircraft flights around the world.  We can input the performance of each aircraft including its environmental performance. As the aircraft fly, we track the amount and location of emissions of CO2 and other effluents like sulfur dioxide. We can also look at noise impacts. Using the tool, we modeled the impact of the current fleet and then the impact of potential levels of the new standard. For a given level, of the airplanes that didn’t meet the standard, we created new designs for those airplane types, and flew the new designs, and modeled what the changed standard’s overall environmental impact would be. At the same time we modeled how much it would cost the industry to do this. Q: This whole process sounds very similar to the wider climate talks that happened in Paris, which did not address aircraft emissions. What do these new standards say about the aviation industry’s contribution to and potential mitigation of global CO2? A: Part of the reason aircraft were not specifically addressed [in Paris] is because they’re addressed within the ICAO process. Aviation is one of the few areas for which there is a well-established international process for a common set of operational rules and standards, because airplanes commonly fly around the world. So a system already exists; however, even with our current international aviation processes, agreeing on a CO2 standard was a major challenge. I also want to say, aviation represents about 2 percent of man-made or anthropogenic CO2 emissions.  However, aviation does not have the alternatives (e.g. solar, nuclear, wind) that other emitters such as electrical power generation have. Aircraft have to lift their fuel source, so high energy-density fuels are important. Fossil fuels are currently the most practical. There is much work going on to develop biofuels, but aviation will be just one of the interested users if biofuels can be produced at scale. I see environmental issues as the largest existential threat to aviation; however I also see aviation as a critical link in solving worldwide environmental challenges. Aviation allows and enables the connections between people around the world, which we need to agree to and implement worldwide solutions to these global challenges. (Comment on this)
2:00p	Bringing more data to language debate A heated controversy in linguistics in recent years involves a few hundred people deep in the Amazonian rainforest: the Pirahã tribe of Northern Brazil. Their idiosyncratic language has raised questions about how widely  human languages share certain characteristics. Among the questions at issue is whether the Pirahã language contains recursion, a process through which sentences (and thus languages) can be expanded infinitely. Consider the sentence, “John wrote a book.” We can add to it and, for instance, form noun phrases that contain multiple noun phrases themselves. Thus, “John and the man wrote a book” might be viewed as evidence of recursion. Some linguists, including one who did some early fieldwork on the Pirahã, have argued that their language lacks recursion, making it anomalous among the world’s tongues. Others, including some experts in MIT’s Department of Linguistics, have disagreed with such claims. Many linguists view all languages as having universal affinities that help us understand what is unique about human language. Now a newly published study co-authored by scholars in MIT’s Department of Brain and Cognitive Sciences (BCS) has made public the most extensive data set yet accumulated on the Pirahã and reached an equivocal conclusion: The findings, they say, make it possible that the Pirahã language lacks recursion, without ruling out the possibility that recursion does exist in the tongue. “We think it’s consistent with there being no recursion, but we can’t say for sure,” says Edward Gibson, a professor in BCS and a co-author of the paper. “It’s plausible.” To reach a more definitive conclusion, Gibson believes, “We would need so much more data.” The current study is based on 1,100 sentences translated from Pirahã — more than ever assembled previously but not a large amount by the standards he has used when analyzing other languages. The scholars are making the corpus available to anyone for future research.  “It’s not just about injecting the data,” Gibson says, suggesting the existence of the corpus means scholars will be less inclined to “talk about an example or two and then have very broad arguments … We want a way of making the raw data available to everyone, so anyone can make their own conclusions based on open access.” Still, even given the larger dataset, the question of whether recursion is absent from the Pirahã language also hinges on the interpretations of scholars who have done fieldwork among the tribe — including Daniel L. Everett, a linguist and the dean of arts and sciences at Bentley University, who is a co-author of the paper and whose early field research has generated the sometimes intense debate on the subject. Disappearing people The paper, “A Corpus Investigation of Syntactic Embedding in Piraha,” was published last week in the journal PLOS One. The co-authors are Gibson; Everett; Richard Futrell, a PhD student in BCS; Laura Stearns, a research assistant in BCS; and Steven Piantadosi, a professor of cognitive science at the University of Rochester. In the 1970s, Everett lived for an extended time among the Pirahã, who reside along the Maici River, which branches off the Amazon. He published a doctoral dissertation on them in the 1980s, but the controversy over the Pirahã language did not explode until 2005, when Everett published a scholarly article making the case for the language’s unique properties, including its apparent lack of recursion. For the current paper, the researchers assembled the corpus by combining the transcriptions of 17 stories told in Pirahã. Those stories were transcribed by Everett and Steve Sheldon, a missionary who lived among the Pirahã people in the 1970s. Using the 1,100 sentences in the corpus, the researchers analyzed each one to see if they could find examples of several types of “recursive embedding.” For instance, they looked for examples of “center embedding,” in which a clause is inserted into the middle of a sentence. No examples of it were present in the Pirahã dataset. However, the issue of whether some Pirahã sentences in the corpus display recursion may also be a matter of translation and interpretation. For example, the use of conjunction in a sentence can lead to boundless new forms of sentences, by joining noun phrases such as “Joe and Sue went to the market.” The set of 1,100 sentences contains five cases that could suggest use of conjunction. In three of those cases, the co-authors believe, this simply represents a close juxtaposition of noun phrases without any special linking of them. In the other two cases, Everett’s translations of the sentences differ from those of Sheldon. Everett believes there is no conjunction in those sentences, although Sheldon’s original translations suggested there was. For instance, a Pirahã sentence transliterated as “ti xaigia ao ogi gio ai hi ahapita” was interpreted by Sheldon to mean, “Well, then I and the big Brazilian woman disappeared.” The conjunction of “I and the big Brazilian woman” could be an example of recursion. But Everett believes a better translation is: “Well, [with respect to me], the very big foreigner went away again.” And that sentence has no recursion. “Let’s get everything out there” The co-authors say they do not expect the current paper to end all debate but rather to help scholars see the comparative frequency (or lack thereof) by which sentences that are even suggestive of recursion appear in Pirahã. In addition, the translations provide more examples of the language in everyday use. As Futrell notes, “I think the approach of analyzing the data in a rigorous way is more important than whatever conclusion we’ve come to about Pirahã recursion.” Futrell also suggests that “the right way to think about universalism is not in terms of all languages [containing] X or Y, but rather that there’s some probability distribution over all the properties languages can have.” Other scholars say it is good to have more data available. Tom Wasow, a professor emeritus of linguistics at Stanford University, who has seen the paper, calls it a “careful, systematic” examination of the corpus, adding: “Probably the most important contribution of the paper is making the corpus publicly available, so that investigators can check for themselves whether they see anything that looks like recursion.” Still, Wasow, who taught Futrell when Futrell was an undergraduate, suggests that even resolving the matter of whether or not Pirahã contains recursion would not negate certain claims about the global affinities of human languages. “Suppose one, or even a few dozen, of the thousands of languages in the world lack recursion,” Wasow states. “Should linguists therefore conclude that recursion is not a general property of language?  I don't think so.” By analogy, Wasow adds, “When biologists discovered the platypus, they did not abandon the generalization that mammals give live birth to their offspring; rather they recognized that it is a characteristic of almost all species of mammals.” David Pesetsky, the Ferrari P. Ward Professor of Modern Languages and Linguistics at MIT, and head of the MIT Department of Linguistics and Philosophy, has previously published articles criticizing Everett’s findings, and believes an alternate analytical approach will be needed to reach any conclusions about the structure of Pirahã. Regarding recursion specifically, for instance, Pesetsky notes that a graduate student at the University of British Columbia, Raiane Salles, has conducted recent fieldwork among the Pirahã unearthing potential evidence of “possessor recursion” — which creates phrases that could expand infinitely, such as “the foreigner’s parent’s dog” and “Migixoi’s husband’s mother’s clothes.” While the current paper has not changed Pesetsky’s position, he notes that he does appreciate having a corpus of Pirahã made public. Gibson says he is willing to see the scholarly debate unfold, based on access to the larger data set: “Let’s get everything out there, and we can all talk about it.” (Comment on this)

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