Fight or flight? Why individuals react as they do

Why do some people fight and others flee when confronting violence? “This question has been bothering me for quite some time,” says Aidan Milliff, a fifth-year doctoral student who entered political science to explore the strategic choices people make in perilous times.

“We’ve learned a great deal how economic status, identity, and pressure from community shape decisions people make while under threat,” says Milliff. Early in his studies, he took particular interest in scholarship linking economic deprivation to engagement in conflict.

“But I became frustrated by this idea, because even among the poorest of the poor, way more people sit out conflict instead of engaging,” he says. “I thought there must be something else going on to explain why people decide to take enormous risks.”

A window on this problem suddenly opened for Milliff with class 17.S950 (Emotions and Politics), taught by Roger Petersen, the Arthur and Ruth Sloan Professor of Political Science. “The course revealed the cognitive processes and emotional experiences that influence how individuals make decisions in the midst of violent conflict,” he says. “It was extremely formative in the kinds of research I started to do.”

With this lens, Milliff began investigating questions anew, leveraging unusual data sources and novel qualitative and quantitative methods. His doctoral research is yielding fresh perspectives on how civilians experience threats of violence, and, Milliff believes, “providing policy-relevant insights, explaining how individual action contributes to phenomena like conflict escalation and refugee flows.”

First-person accounts

At the heart of Milliff’s dissertation project, “Seeking Safety: The Cognitive and Social Foundations of Behavior During Violence,” are connected episodes of violence in India: an urban pogrom in Delhi in which nearly 3,000 Sikhs died at the hands of Hindus, sparked by the 1984 assassination of Indira Gandhi by her Sikh bodyguards; and the bloody, decade-long separatist civil war by Sikh extremists in Punjab that began in the 1980s.

In search of first-person testimony to illuminate people’s fight-or-flight choices, Milliff lucked out: He located taped oral histories for a large population of Sikhs who had experienced violence in the 1980s. “In these 500 taped histories, people described at a granular level whether they organized to defend their neighborhoods, hid in houses, left the city temporarily or permanently, or tried to pass as Hindu.” He also pursued field interviews in California and India, but didn’t get as far as he’d hoped: “I arrived in India last March, and was there for two weeks of an intended three-month stay when I had to return due to the pandemic.”

This setback did not deter Milliff, who managed to convert the oral histories into text and video data that he’s already begun to plumb, with the help of natural language processing to code people’s decision-making processes. Among his preliminary findings: “People typically appraise their situations in terms of their sense of control and of predictability,” he says.

“When people feel they have a high degree of control but feel that violence is unpredictable, they are more likely to fight back, and when they sense they have neither control nor predictability, and more easily imagine being victims, they flee.”

A Chicago launchpad

Milliff drew inspiration for his doctoral research directly from an earlier graduate project in Chicago with the families of homicide victims.

“I wanted to learn whether people who become angry in response to violence are more likely to seek retribution,” he says. After taping 90 hours of interviews with 31 people, primarily mothers, Milliff shifted his focus. “My initial assumption that everyone would get angry was wrong,” he says. “I found that when people suffer these losses, they might get sad instead, or become fearful.” In unsolved homicides, family members have no perpetrator to target, but instead turn their anger at government that’s let them down, or worry for the safety of surviving family members.

From this project, Milliff took away a crucial insight: “People respond differently to their tragedies, even when their experiences look similar on paper.”

Political violence and its consequences seized Milliff’s interest early on. For his University of Chicago master’s thesis, he sought to understand how many long-running, brutal independence movements fizzle out. “I came away from this program believing that I’d enjoy the day-to-day work of being a professional political scientist,” he says.

Two research experiences propelled him toward that goal. While in college, Milliff assisted in the National Science Foundation-sponsored General Social Survey, a national social survey headquartered in Chicago, where he learned “how a big quantitative data collection exercise works,” he says. Following graduation, a fellowship at the Carnegie Endowment for International Peace immersed him in South Asian military conflict and Indian domestic politics. “I really enjoyed working on these issues and became greatly interested in focusing on the political situation there,” he says.

Attracted by MIT’s security studies community, especially its commitment to research with real-world impact, Milliff came to Cambridge, Massachusetts, primed to delve deeper into the subject of political violence. He first had to navigate the graduate program’s thorough quantitative sequence. “I came to MIT without having taken math after calculus, and I honestly feel fortunate I ended up somewhere that takes the classroom portion of training seriously,” he says. “It has given me new tools I didn’t even know existed.”

These tools are integral to Milliff’s analysis of his singular datasets, and provide the quantitative foundation for informing his policy ideas. If, as his work suggests, people in crisis make decisions based on their sense of control and predictability, perhaps community institutions could bolster citizens’ abilities to imagine concrete options. “Lack of predictability and a sense of control encourage people to make choices that are destabilizing, such as fleeing their homes, or joining a fight.”

Milliff continues to analyze data, test hypotheses, and write up his research, taking time out for biking and nature photography. “When I was headed to graduate school, I decided to take up a hobby that I could do for 15 minutes at a time, something I could do between problem sets,” he says.

While he acknowledges research can be taxing, he takes delight in the moments of discovery and validation: “You spend a lot of time coming up with ideas of how the world works, diving into a pit to see if an idea is right,” he says. “Sometimes when you surface, you see that you might have come up with a possible new way to describe the world.”

de MIT News https://ift.tt/3uqmu0I

Improving sanitation for the world’s most vulnerable people

Last year, women visiting a neonatal clinic at a hospital in Kiboga, Uganda, began using two waterless, standalone bathrooms that offered a cleaner and more private alternative to the pit latrines that are standard in the region.

The deployment was the culmination of years of work by the startup change:WATER Labs, co-founded by two MIT research scientists — and its success showed the company’s potential to improve lives far beyond Uganda.

Half of the world’s population lacks access to toilets that safely manage human waste, with women and children bearing the brunt of the consequences. A child dies every 15 seconds from water-related diseases like diarrhea and cholera. Women and girls without private bathrooms close to their homes are susceptible to high rates of sexual violence. Globally, 45 percent of schools lack proper bathroom facilities, one reason 20 percent of girls drop out of school by the time they start menstruating.

The small but determined team behind change:WATER Labs believes the solution to these problems is an inexpensive, no-flush toilet that can be dropped into any location and work without external power. The toilet, which the company calls the iThrone, uses a proprietary material to evaporate the water content of human waste, shrinking waste by 95 percent, thus preventing waste discharge and simplifying waste collection.

The breathable material takes advantage of the natural tendency of water molecules to move from areas of high moisture to areas of low moisture. CEO and co-founder Diana Yousef, who is also a research affiliate at MIT, says the iThrone allows for waste collection once or twice a month as opposed to every day, transforming the economics of distributed sanitation in low-resource communities.

“We’re essentially turning human waste into clean molecular water, and what’s left over gets collected much less frequently at much lower cost,” Yousef says. “The solution helps customers managing sanitation to be much more scalable, much more sustainable, and much more profitable.”

Today change:WATER Labs has promising early trial results to go along with support from a host of companies, NGOs, and governments. But back when the company was nothing more than an idea, MIT played a pivotal role in making the iThrone concept a reality.

A unique partnership

The seed of change:WATER Labs was planted for Yousef while working on a water treatment initiative with NASA in 2009. Although the project explored ways to recycle water for space agriculture, Yousef wondered if any of the approaches could be used to improve water sustainability in the developing world.

Five years later, she finally put the idea to paper, pitching an early version at MIT’s Water Innovation Prize and the MIT IDEAS Social Innovation Challenge. The experience helped her connect with others at MIT who were interested in the idea, including co-founder Huda Elasaad, a research affiliate in MIT’s D-Lab. Yousef, who earned her undergraduate degree at Harvard University, a PhD at Cornell University, and MBA and MIA degrees from Columbia University, eventually received seed funding to explore the idea from IDEAS and the MIT PKG Center. The support allowed her team to gain access to lab facilities for early testing.

“[The early support from MIT] was a game-changer for us, because you start to have doubts about whether what you’re doing is possible, and when some other entity like MIT takes a bet on you, you start to believe it yourself,” says Yousef, who notes she didn’t have the resources to pursue the idea on her own and was working on a prototype in her kitchen.

MIT’s relationship with the company has continued to evolve in the years since that early bet. MIT’s Environment, Health, and Safety (EHS) Office has helped the startup develop its waste treatment system, and the company benefits from its association with MIT D-Lab, where it collaborates with MIT students from diverse backgrounds.

“We’ve been so very lucky to find such support and collaborators at MIT,” Yousef says. “MIT provides a truly unique ecosystem that cultivates partnerships between innovators within and around MIT to catalyze world-changing innovations. Our breakthrough wouldn’t have been possible without the support from D-Lab, EHS, the PKG Center, and our other partners at MIT.”

On a mission for change

Change:WATER Labs’ toilets were used by about 400 people per week in Uganda before the project was cut short by Covid-19. Yousef says the iThrones proved safe, with minimal odor and no leakage, showing they could be placed close to densely populated areas.

“We have the potential to put safe, hygienic, clean toilets in places that are crowded and close to where people are, and that’s been one of the challenges with other solutions, like composting toilets and others, that don’t fit in crowded communities,” she says.

The toilets also reduced daily waste volumes so much that they were able to operate for weeks at a time without being serviced. Overall, Yousef says feedback from users was overwhelmingly positive as the iThrones provided a safer, cleaner alternative to pit latrines located on the top of a remote hill.

Although travel restrictions have put other iThrone pilots on hold, change:WATER Labs has received funding from the Bill and Melinda Gates Foundation, the United Nations Development Program, and the Turkish government to install its toilets in refugee communities in Turkey later this year.

Private companies have also expressed interest, including two large construction contractors looking to put iThrones in low-income homes in Central America, and two Indian companies seeking to put iThrones in port-a-potties and on transportation and maritime equipment.

Yousef says that inbound interest is indicative of the large global need and pent-up demand for better sanitation options.

“We need new solutions that contain and eliminate human waste while also reducing the amount of water that gets consumed, preventing pollution,” Yousef says. “We solve all of that.”

Yousef says the company never would have reached this point without the MIT community, which she commends for embracing her effort even though she is not an alumna.

“MIT’s willingness to open up its community to the innovators around it allows for things to happen that really don’t happen anywhere else,” she says. “It’s special to be here and it’s really amplified what we’re trying to do.”

de MIT News https://ift.tt/3dEy5mz

Amy Jin named 2021 Gates Cambridge Scholar

MIT senior Amy Jin has won the prestigious Gates Cambridge Scholarship, which offers students an opportunity to pursue graduate study in the field of their choice at the University of Cambridge in the UK. Jin will join the other 23 U.S. citizens in being members of the 20th class of scholars.

Jin, from Pleasanton, California, is completing double majors in biological engineering and electrical engineering and computer science. During her time volunteering as an aquarist at the New England Aquarium, she became fascinated by the power and cruelty of evolution. She wishes to harness the power she observed in natural phenomena, such as the “virgin birth” she witnessed of a baby green anaconda, to inspire engineering designs related to human health. At Cambridge, she plans to conduct research in bioelectronics to develop medical technology for treating neurological disorders.

Her studies at Cambridge will build upon her undergraduate research in the Langer and Traverso labs, where she has worked on evaluating polymer hydrogel drug delivery systems and designing microbiome-based therapies that target inflamed parts of the gastrointestinal tract. In fall 2019, she began work in the Bathe Lab, which uses DNA and RNA to engineer new nanoscale materials for therapeutics and computing. Jin specifically worked on DNA storage and computation. Professor Mark Bathe says, “I was thrilled to learn of the wonderful news that Amy received the Gates Cambridge Scholarship. Amy combines the highest levels of creativity, technical and intellectual depth and breadth, leadership, and motivation for her work to impact society — I cannot imagine a more deserving candidate for this prestigious award.” She is also a NEET Living Machines scholar.

Jin has been an active volunteer at the New England Aquarium and a garden chair for UA Sustainability. She was a member of Terrascope, a first-year learning community that tackles a global issue related to sustainability. She has volunteered with the Petey Greene Program, providing tutoring to incarcerated people. She participated in MIT’s service center Criminal Justice Immersion Program, which brought students to local detention centers, trials courts, and the Massachusetts attorney general’s office. She worked for the Massachusetts Trial Court as a recidivism analyst. She worked as an extern with the Massachusetts Eye and Ear Glaucoma Clinic and has been dedicated to the HMS Family Van, which performs free health screenings in their mobile clinic. She is an Emerson piano scholar and participates in the MIT Chamber Music Society.

Jin was advised in her application by Kim Benard of the Distinguished Fellowships team in Career Advising and Professional Development, who remarks, “Amy represents the best of MIT, pursuing scientific research with passion and excitement. She applies the lessons she has learned volunteering with the aquarium to create innovative solutions for human health. But even more than her abilities in science, she has demonstrated remarkable empathy and compassion for others, demonstrated through her volunteer activities.”

Established by the Bill and Melinda Gates Foundation in 2000, the Gates Cambridge Scholarship provides full funding for talented students from outside the United Kingdom to pursue postgraduate study in any subject at Cambridge University. Since the program’s inception in 2001, there have been 32 Gates Cambridge scholars from MIT.

de MIT News https://ift.tt/37G0NQu

Study: Covid-19 communications featuring racially diverse physicians can improve health outcomes for communities of color

In a new study by MIT professors Esther Duflo, Ben Olken, and Abhijit Banerjee, and physicians Marcella Alsan and Fatima Cody Stanford, along with other doctors and economists, public health video messages featuring a racially diverse set of physicians were found to decrease knowledge gaps about Covid-19 symptoms and transmission — generating important lessons about how we communicate about, and work to mitigate the effects of, the virus. Study results also indicated that, for Black individuals, watching a video with a racially concordant (Black) physician increased the degree to which they sought out more information about Covid-19.

Black and Latinx communities have significantly higher infection and mortality rates and are more likely to have severe symptoms and be hospitalized as a result of the Covid-19 pandemic compared to white communities. Although these disparities stem from many complex factors, including inequalities in access to health care, systemic racism, and the overrepresentation of communities of color in front-line and essential jobs, one contributing factor may be knowledge gaps around Covid-19 symptoms and transmission. To date, few public health messages around the coronavirus pandemic directly address communities of color and, as a result, these communities may be left behind in the nationwide efforts to contain, respond to, and recover from the pandemic.

The study evaluated the effectiveness of three different video messages about the coronavirus that varied in three ways: the featured physician’s race or ethnicity, the degree to which the physician acknowledged the difficulties faced by communities of color in accessing health services, and messaging around community perceptions of wearing a mask. Physicians from Massachusetts General Hospital (MGH) and Lynn Community Health Center of different racial and ethnic backgrounds were featured in the study’s videos.

“Our motivation to pursue this work stems out of the significant racial and ethnic disparities in access to and take-up of health services that have been widened and intensified by Covid-19,” says Marcella Alsan, professor of public policy at Harvard Kennedy School and co-chair of J-PAL North America’s Health Care Delivery Initiative, part of MIT’s Abdul Latif Jameel Poverty Action Lab.

The findings underscore the importance of physician-delivered messages in increasing knowledge about the virus’ prevention, symptoms, and transmission. They also echo findings of other research demonstrating that race concordance between a patient and physician can increase take-up of health services for Black individuals. For Latinx individuals included in the study, watching a video with a ethnically concordant (Latinx) physician did not impact information-seeking behavior.

As the authors of the study note, increasing knowledge about Covid-19 is only a first step to decreasing transmission and mitigating the negative impacts of the virus. However, given the large gaps in knowledge about Covid-19 among Black and Latinx communities, ensuring that critical public health information is effectively reaching those most impacted by the pandemic is of paramount importance. Increasing the racial diversity of our physician workforce is a longer-term strategy to decrease persistent health inequities, both in the age of Covid-19 and after the worst impacts of the pandemic subside.

de MIT News https://ift.tt/37yR7qD

New “metalens” shifts focus without tilting or moving

Polished glass has been at the center of imaging systems for centuries. Their precise curvature enables lenses to focus light and produce sharp images, whether the object in view is a single cell, the page of a book, or a far-off galaxy.

Changing focus to see clearly at all these scales typically requires physically moving a lens, by tilting, sliding, or otherwise shifting the lens, usually with the help of mechanical parts that add to the bulk of microscopes and telescopes.

Now MIT engineers have fabricated a tunable “metalens” that can focus on objects at multiple depths, without changes to its physical position or shape. The lens is made not of solid glass but of a transparent “phase-changing” material that, after heating, can rearrange its atomic structure and thereby change the way the material interacts with light.

The researchers etched the material’s surface with tiny, precisely patterned structures that work together as a “metasurface” to refract or reflect light in unique ways. As the material’s property changes, the optical function of the metasurface varies accordingly. In this case, when the material is at room temperature, the metasurface focuses light to generate a sharp image of an object at a certain distance away. After the material is heated, its atomic structure changes, and in response, the metasurface redirects light to focus on a more distant object.

In this way, the new active “metalens” can tune its focus without the need for bulky mechanical elements. The novel design, which currently images within the infrared band, may enable more nimble optical devices, such as miniature heat scopes for drones, ultracompact thermal cameras for cellphones, and low-profile night-vision goggles.

“Our result shows that our ultrathin tunable lens, without moving parts, can achieve aberration-free imaging of overlapping objects positioned at different depths, rivaling traditional, bulky optical systems,” says Tian Gu, a research scientist in MIT’s Materials Research Laboratory.

Gu and his colleagues have published their results today in the journal Nature Communications. His co-authors include Juejun Hu, Mikhail Shalaginov, Yifei Zhang, Fan Yang, Peter Su, Carlos Rios, Qingyang Du, and Anuradha Agarwal at MIT; Vladimir Liberman, Jeffrey Chou, and Christopher Roberts of MIT Lincoln Laboratory; and collaborators at the University of Massachusetts at Lowell, the University of Central Florida, and Lockheed Martin Corporation.

A material tweak

The new lens is made of a phase-changing material that the team fabricated by tweaking a material commonly used in rewritable CDs and DVDs. Called GST, it comprises germanium, antimony, and tellurium, and its internal structure changes when heated with laser pulses. This allows the material to switch between transparent and opaque states — the mechanism that enables data stored in CDs to be written, wiped away, and rewritten.

Earlier this year, the researchers reported adding another element, selenium, to GST to make a new phase-changing material: GSST. When they heated the new material, its atomic structure shifted from an amorphous, random tangle of atoms to a more ordered, crystalline structure. This phase shift also changed the way infrared light traveled through the material, affecting refracting power but with minimal impact on  transparency.

The team wondered whether GSST’s switching ability could be tailored to direct and focus light at specific points depending on its phase. The material then could serve as an active lens, without the need for mechanical parts to shift its focus.

“In general when one makes an optical device, it’s very challenging to tune its characteristics postfabrication,” Shalaginov says. “That’s why having this kind of platform is like a holy grail for optical engineers, that allows [the metalens] to switch focus efficiently and over a large range.”

In the hot seat

In conventional lenses, glass is precisely curved so that incoming light beam refracts off the lens at various angles, converging at a point a certain distance away, known as the lens’ focal length. The lenses can then produce a sharp image of any objects at that particular distance. To image objects at a different depth, the lens must physically be moved.

Rather than relying on a material’s fixed curvature to direct light, the researchers looked to modify GSST-based metalens in a way that the focal length changes with the material’s phase.

In their new study, they fabricated a 1-micron-thick layer of GSST and created a “metasurface” by etching the GSST layer into microscopic structures of various shapes that refract light in different ways.

“It’s a sophisticated process to build the metasurface that switches between different functionalities, and requires judicious engineering of what kind of shapes and patterns to use,” Gu says. “By knowing how the material will behave, we can design a specific pattern which will focus at one point in the amorphous state, and change to another point in the crystalline phase.”

They tested the new metalens by placing it on a stage and illuminating it with a laser beam tuned to the infrared band of light. At certain distances in front of the lens, they placed transparent objects composed of double-sided patterns of horizontal and vertical bars, known as resolution charts, that are typically used to test optical systems.

The lens, in its initial, amorphous state, produced a sharp image of the first pattern. The team then heated the lens to transform the material to a crystalline phase. After the transition, and with the heating source removed, the lens produced an equally sharp image, this time of the second, farther set of bars.

“We demonstrate imaging at two different depths, without any mechanical movement,” Shalaginov says.

The experiments show that a metalens can actively change focus without any mechanical motions. The researchers say that a metalens could be potentially fabricated with integrated microheaters to quickly heat the material with short millisecond pulses. By varying the heating conditions, they can also tune to other material’s intermediate states, enabling continuous focal tuning.

“It’s like cooking a steak — one starts from a raw steak, and can go up to well done, or could do medium rare, and anything else in between,” Shalaginov says. “In the future this unique platform will allow us to arbitrarily control the focal length of the metalens.”

de MIT News https://ift.tt/3uoKD7U

Researchers develop speedier network analysis for a range of computer hardware

Graphs — data structures that show the relationship among objects — are highly versatile. It’s easy to imagine a graph depicting a social media network’s web of connections. But graphs are also used in programs as diverse as content recommendation (what to watch next on Netflix?) and navigation (what’s the quickest route to the beach?). As Ajay Brahmakshatriya summarizes: “graphs are basically everywhere.”

Brahmakshatriya has developed software to more efficiently run graph applications on a wider range of computer hardware. The software extends GraphIt, a state-of-the-art graph programming language, to run on graphics processing units (GPUs), hardware that processes many data streams in parallel. The advance could accelerate graph analysis, especially for applications that benefit from a GPU’s parallelism, such as recommendation algorithms.

Brahmakshatriya, a PhD student in MIT’s Department of Electrical Engineering and Computer Science and the Computer Science and Artificial Intelligence Laboratory, will present the work at this month’s International Symposium on Code Generation and Optimization. Co-authors include Brahmakshatriya’s advisor, Professor Saman Amarasinghe, as well as Douglas T. Ross Career Development Assistant Professor of Software Technology Julian Shun, postdoc Changwan Hong, recent MIT PhD student Yunming Zhang PhD ’20 (now with Google), and Adobe Research’s Shoaib Kamil.

When programmers write code, they don’t talk directly to the computer hardware. The hardware itself operates in binary — 1s and 0s — while the coder writes in a structured, “high-level” language made up of words and symbols. Translating that high-level language into hardware-readable binary requires programs called compilers. “A compiler converts the code to a format that can run on the hardware,” says Brahmakshatriya. One such compiler, specially designed for graph analysis, is GraphIt.

The researchers developed GraphIt in 2018 to optimize the performance of graph-based algorithms regardless of the size and shape of the graph. GraphIt allows the user not only to input an algorithm, but also to schedule how that algorithm runs on the hardware. “The user can provide different options for the scheduling, until they figure out what works best for them,” says Brahmakshatriya. “GraphIt generates very specialized code tailored for each application to run as efficiently as possible.”

A number of startups and established tech firms alike have adopted GraphIt to aid their development of graph applications. But Brahmakshatriya says the first iteration of GraphIt had a shortcoming: It only runs on central processing units or CPUs, the type of processor in a typical laptop.

“Some algorithms are massively parallel,” says Brahmakshatriya, “meaning they can better utilize hardware like a GPU that has 10,000 cores for execution.” He notes that some types of graph analysis, including recommendation algorithms, require a high degree of parallelism. So Brahmakshatriya extended GraphIt to enable graph analysis to flourish on GPUs.

Brahmakshatriya’s team preserved the way GraphIt users input algorithms, but adapted the scheduling component for a wider array of hardware. “Our main design decision in extending GraphIt to GPUs was to keep the algorithm representation exactly the same,” says Brahmakshatriya. “Instead, we added a new scheduling language. So, the user can keep the same algorithms that they had before written before [for CPUs], and just change the scheduling input to get the GPU code.”

This new, optimized scheduling for GPUs gives a boost to graph algorithms that require high parallelism — including recommendation algorithms or internet search functions that sift through millions of websites simultaneously. To confirm the efficacy of GraphIt’s new extension, the team ran 90 experiments pitting GraphIt’s runtime against other state-of-the-art graph compilers on GPUs. The experiments included a range of algorithms and graph types, from road networks to social networks. GraphIt ran fastest in 65 of the 90 cases and was close behind the leading algorithm in the rest of the trials, demonstrating both its speed and versatility.

GraphIt “advances the field by attaining performance and productivity simultaneously,” says Adrian Sampson, a computer scientist at Cornell University who was not involved with the research. “Traditional ways of doing graph analysis have one or the other: Either you can write a simple algorithm with mediocre performance, or you can hire an expert to write an extremely fast implementation — but that kind of performance is rarely accessible to mere mortals. The GraphIt extension is the key to letting ordinary people write high-level, abstract algorithms and nonetheless getting expert-level performance out of GPUs.”

Sampson adds the advance could be particularly useful in rapidly changing fields: “An exciting domain like that is genomics, where algorithms are evolving so quickly that high-performance expert implementations can’t keep up with the rate of change. I’m excited for bioinformatics practitioners to get their hands on GraphIt to expand the kinds of genomic analyses they’re capable of.”

Brahmakshatriya says the new GraphIt extension provides a meaningful advance in graph analysis, enabling users to go between CPUs and GPUs with state-of-the-art performance with ease. “The field these days is tooth-and-nail competition. There are new frameworks coming out every day,” He says. But he emphasizes that the payoff for even slight optimization is worth it. “Companies are spending millions of dollars each day to run graph algorithms. Even if you make it run just 5 percent faster, you’re saving many thousands of dollars.”

This research was funded, in part, by the National Science Foundation, U.S. Department of Energy, the Applications Driving Architectures Center, and the Defense Advanced Research Projects Agency.

de MIT News https://ift.tt/2NKNN4Q

Giving the people what they want?

At times it can feel like public opinion does not matter in U.S. politics. When the U.S. Congress or state legislatures ignore issues that have broad public support, there seems to be a glaring gap between what people want and what politicians will deliver.

But in due course, public opinion does sway elected officials, according to MIT political scientist Devin Caughey. Indeed, Caughey’s work has shown that at the state level in the U.S. over the last several decades, government policies have followed public views — often incrementally, but consistently.

“Over the long term, policymaking tends to be responsive to public opinion and move into alignment with what the public wants,” says Caughey. That has become more apparent due to innovative research Caughey and his colleagues have performed while using thousands of public-opinion opinion surveys from the 1930s onward.

But Caughey, who calls himself “a political scientist who studies historical things,” has also found the power of public opinion at work at the federal level. In his 2018 book “The Unsolid South,” published by the Princeton University Press, Caughey explores the varieties of Southern responses to the New Deal, showing how public attitudes about it varied across time and place, with Washington following suit.

Now Caughey, along with political scientist Chris Warshaw of George Washington University, is working on another large book project, “Dynamic Democracy: Citizens, Parties, and Policymakers in the American State,” about their state-level findings. On either scale, the research shows something important: Democracy works, albeit in fits and starts.

Yes, at any given moment, Caughey notes, “Policies are often mismatched with public opinion. A majority of the public may want a minimum wage of $15, but the minimum wage is $7. It happens a lot, for a variety of reasons. Then gradually the match improves. And then often polling stops, because the issues that are in alignment aren’t as controversial any more.”

Working across disciplines

Caughey hails from California, but attended high school in Pennsylvania. As an undergraduate at Yale University, he received his BA in history, mostly focusing on  Latin America and ancient Greece. But in his senior year, a seminar with political scientist David Mayhew, a leading scholar of Congress, sparked Caughey’s interest. Caughey entered a master’s program at Cambridge University, receiving an MPhil in history while writing a thesis on the New Deal and the South. Finally he pursued a PhD in political science at the University of California at Berkeley.

“I was interested in representation, the relationship between public opinion, what the people say they want, and what elites are doing, members of Congress in particular,” Caughey says. His thesis at Berkeley became the foundation for “The Unsolid South.” Caughey received his PhD in 2012 and joined MIT later that year. Now an associate professor, he was awarded tenure in 2020.

Caughey’s research at MIT has had three fronts: his work on the South and the New Deal; his research on state-level politics; and methodological work about polling data. On the last subject, Caughey and six colleagues published a short monograph in 2020 about extracting useful data from older surveys.

By contrast, “The Unsolid South” blended both political science and history to update received thinking about the South in the 1930s and 1940s.

“The conventional wisdom was and perhaps still is that Southern members of Congress were essentially unresponsive to public opinion,” Caughey says. With many of them assured of reelection, and with nearly all Black Southerners disenfranchised, the idea goes, U.S. representatives could ignore their constituents.

“What I tried to show in my book is, I don’t think that’s true,” says Caughey. “White Southerners were very supportive of the New Deal until the mid-1930s and turned very sharply against it, and so did their representatives. And similarly the kinds of states that were more supportive of the New Deal within the South had representatives that were more supportive.”

Ultimately “The Unsolid South” spoke to both political scientists and historians by highlighting how the New Deal coalition shrunk once its measures seemed likely to help Black people. In addition to winning the American Political Science Association’s award for best book on parties and political organizations, Caughey’s book received an honorable mention from the Social Science History Association.

“That for me was really gratifying, that it was speaking to a broader audience,” Caughey says.

A full picture of politics

At present, Caughey is focused on the “Dynamic Democracy” project, in which he and Warshaw scrutinize all states from 1936 to 2014.

“We can really paint this holistic picture of the political process, where we can look at public opinion, and elections, and parties, and policymaking, all within this common framework, and look at how those different pieces of the political process respond to each other over time,” Caughey says.

The project explores many intricacies regarding public opinion. Passing legislation, for one thing, can itself help solidify the public popularity of certain ideas.

“Initially Social Security was fairly popular when it was first passed [in the 1930s], but not overwhelmingly popular,” Caughey says. “But once people got Social Security, it became very, very popular.”

Public opinion also limits state-level policy radicalism by hovering in the political middle: “When policy moves to the right, it increases the number of people who thinks it should move back to the left again, and vice versa,” Caughey observes.

There is one way that political parties can get around the restraining force of public opinion: gerrymandering, which lets parties perpetuate their hold on legislatures.

“One thing that really seems to have a bad effect on the relationship between public opinion and policy outcomes is partisan gerrymandering,” Caughey notes. “The best thing we’ve found for improving the translation between public opinion and policy outcomes is taking [redistricting] power outside the hands of parties and putting in a citizens’ redistricting commission.”

Caughey and Warshaw are not taking a panglossian view of U.S. politics. Of the 1930s, Caughey says, “I don’t like to call the one-party South a democracy, because it had a number of features like the disenfranchisement of a big part of the population.”

He emphasizes the “gradations between authoritarianism and democracy. There are some democracies that don’t work quite right, that have some authoritarian features even today. But there are also a lot of authoritarian regimes that have democratic-like features and they’re not just window dressing; they do change the incentives of elites. Exploring that gray area has become a core part of the book.”

But given an appropriate level of critical thinking, Caughey’s research still suggests that democracy reflects the will of the people, over time.

“The message we’re trying to drive home in this book is that when you take a longer-term view of representation, things look better than when you look in the short term,” Caughey says. “In some ways our work is relatively optimistic about this subject.”

de MIT News https://ift.tt/2ZO7ZFX