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      Driving toward data justice

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      As a person with a mixed-race background who has lived in four different cities, Amelia Dogan describes her early life as “growing up in a lot of in-betweens.” Now an MIT senior, she continues to link different perspectives together, working at the intersection of urban planning, computer science, and social justice.

      Dogan was born in Canada but spent her high school years in Philadelphia, where she developed a strong affinity for the city.  

      “I love Philadelphia to death,” says Dogan. “It’s my favorite place in the world. The energy in the city is amazing — I’m so sad I wasn’t there for the Super Bowl this year — but it is a city with really big disparities. That drives me to do the research that I do and shapes the things that I care about.”

      Dogan is double-majoring in urban science and planning with computer science and in American studies. She decided on the former after participating in the pre-orientation program offered by the Department of Urban Studies and Planning, which provides an introduction to both the department and the city of Boston. She followed that up with a UROP research project with the West Philadelphia Landscape Project, putting together historical census data on housing and race to find patterns for use in community advocacy.

      After taking WGS.231 (Writing About Race), a course offered by the Program in Women’s and Gender Studies, her first year at MIT, Dogan realized there was a lot of crosstalk between urban planning, computer science, and the social sciences.

      “There’s a lot of critical social theory that I want to have background in to make me a better planner or a better computer scientist,” says Dogan. “There’s also a lot of issues around fairness and participation in computer science, and a lot of computer scientists are trying to reinvent the wheel when there’s already really good, critical social science research and theory behind this.”

      Data science and feminism

      Dogan’s first year at MIT was interrupted by the onset of the Covid-19 pandemic, but there was a silver lining. An influx of funding to keep students engaged while attending school virtually enabled her to join the Data + Feminism Lab to work on a case study examining three places in Philadelphia with historical names that were renamed after activist efforts.

      In her first year at MIT, Dogan worked several UROPs to hone her own skills and find the best research fit. Besides the West Philadelphia Land Project, she worked on two projects within the MIT Sloan School of Management. The first involved searching for connections between entrepreneurship and immigration among Fortune 500 founders. The second involved interviewing warehouse workers and writing a report on their quality of life.

      Dogan has now spent three years in the Data + Feminism Lab under Associate Professor Catherine D’Ignazio, where she is particularly interested in how technology can be used by marginalized communities to invert historical power imbalances. A key concept in the lab’s work is that of counterdata, which are produced by civil society groups or individuals in order to counter missing data or to challenge existing official data.

      Most recently, she completed a SuperUROP project investigating how femicide data activist organizations use social media. She analyzed 600 social media posts by organizations across the U.S. and Canada. The work built off the lab’s greater body of work with these groups, which Dogan has contributed to by annotating news articles for machine-learning models.

      “Catherine works a lot at the intersection of data issues and feminism. It just seemed like the right fit for me,” says Dogan. “She’s my academic advisor, she’s my research advisor, and is also a really good mentor.”

      Advocating for the student experience

      Outside of the classroom, Dogan is a strong advocate for improving the student experience, particularly when it intersects with identity. An executive board member of the Asian American Initiative (AAI), she also sits on the student advisory council for the Office of Minority Education.

      “Doing that institutional advocacy has been important to me, because it’s for things that I expected coming into college and had not come in prepared to fight for,” says Dogan. As a high schooler, she participated in programs run by the University of Pennsylvania’s Pan-Asian American Community House and was surprised to find that MIT did not have an equivalent organization.

      “Building community based upon identity is something that I’ve been really passionate about,” says Dogan. “For the past two years, I’ve been working with AAI on a list of recommendations for MIT. I’ve talked to alums from the ’90s who were a part of an Asian American caucus who were asking for the same things.”

      She also holds a leadership role with MIXED @ MIT, a student group focused on creating space for mixed-heritage students to explore and discuss their identities.

      Following graduation, Dogan plans to pursue a PhD in information science at the University of Washington. Her breadth of skills has given her a range of programs to choose from. No matter where she goes next, Dogan wants to pursue a career where she can continue to make a tangible impact.

      “I would love to be doing community-engaged research around data justice, using citizen science and counterdata for policy and social change,” she says. More

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      Illuminating the money trail

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      You may not know this, but the U.S. imposes a 12.5 percent import tariff on imported flashlights. However, for a product category the federal government describes as “portable electric lamps designed to function by their own source of energy, other than flashlights,” the import tariff is just 3.5 percent.

      At a glance, this seems inexplicable. Why is one kind of self-powered portable light taxed more heavily than another? According to MIT political science professor In Song Kim, a policy discrepancy like this often stems from the difference in firms’ political power, as well as the extent to which firms are empowered by global production networks. This is a subject Kim has spent years examining in detail, producing original scholarly results while opening up a wealth of big data about politics to the public.

      “We all understand companies as being important economic agents,” Kim says. “But companies are political agents, too. They are very important political actors.”

      In particular, Kim’s work has illuminated the effects of lobbying upon U.S. trade policy. International trade is often presented as an unalloyed good, opening up markets and fueling growth. Beyond that, trade issues are usually described at the industry level; we hear about what the agriculture lobby or auto industry wants. But in reality, different firms want different things, even within the same industry.

      As Kim’s work shows, most firms lobby for policies pertaining to specific components of their products, and trade policy consists heavily of carve-outs for companies, not industry-wide standards. Firms making non-flashlight portable lights, it would seem, are good at lobbying, but the benefits clearly do not carry over to all portable light makers, as long as products are not perfect substitutes for each other. Meanwhile, as Kim’s research also shows, lobbying helps firms grow faster in size, even as lobbying-influenced policies may slow down the economy as a whole.

      “All our existing theories suggest that trade policy is a public good, in the sense that the benefits of open trade, the gains from trade, will be enjoyed by the public and will benefit the country as a whole,” Kim says. “But what I’ve learned is that trade policies are very, very granular. It’s become obvious to me that trade is no longer a public good. It’s actually a private good for individual companies.”

      Kim’s work includes over a dozen published journal articles over the last several years, several other forthcoming research papers, and a book he is currently writing. At the same time, Kim has created a public database, LobbyView, which tracks money in U.S. politics extending back to 1999. LobbyView, as an important collection of political information, has research, educational, and public-interest applications, enabling others, in academia or outside it, to further delve into the topic.

      “I want to contribute to the scholarly community, and I also want to create a public [resource] for our MIT community [and beyond], so we can all study politics through it,” Kim says.

      Keeping the public good in sight

      Kim grew up in South Korea, in a setting where politics was central to daily life. Kim’s grandfather, Kim jae-soon, was the Speaker of the National Assembly in South Korea from 1988 through 1990 and an important figure in the country’s government.

      “I’ve always been fascinated by politics,” says Kim, who remembers prominent political figures dropping by the family home when he was young. One of the principal lessons Kim learned about politics from his grandfather, however, was not about proximity to power, but the importance of public service. The enduring lesson of his family’s engagement with politics, Kim says, is that “I truly believe in contributing to the public good.”

      Kim’s found his own way of contributing to the public good not as a politician but as a scholar of politics. Kim received his BA in political science from Yonsei University in Seoul but decided he wanted to pursue graduate studies in the U.S. He earned an MA in law and diplomacy from the Fletcher School of Tufts University, then an MA in political science at George Washington University. By this time, Kim had become focused on the quantitative analysis of trade policy; for his PhD work, he attended Princeton University and was awarded his doctorate in 2014, joining the MIT faculty that year.

      Among the key pieces of research Kim has published, one paper, “Political Cleavages within Industry: Firm-level Lobbying for Trade Liberalization,” published in the American Political Science Review and growing out of his dissertation research, helped show how remarkably specialized many trade policies are. As of 2017, the U.S. had almost 17,000 types of products it made tariff decisions about. Many of these are the component parts of a product; about two-thirds of international trade consists of manufactured components that get shipped around during the production process, rather than raw goods or finished products. That paper won the 2018 Michael Wallerstein Award for the best published article in political economy in the previous year.

      Another 2017 paper Kim co-authored, “The Charmed Life of Superstar Exporters,” from the Journal of Politics, provides more empirical evidence of the differences among firms within an industry. The “superstar” firms that are the largest exporters tend to lobby the most about trade politics; a firm’s characteristics reveal more about its preferences for open trade than the possibility that its industry as a whole will gain a comparative advantage internationally.

      Kim often uses large-scale data and computational methods to study international trade and trade politics. Still another paper he has co-authored, “Measuring Trade Profile with Granular Product-level Trade Data,” published in the American Journal of Political Science in 2020, traces trade relationships in highly specific terms. Looking at over 2 billion observations of international trade data, Kim developed an algorithm to group countries based on which products they import and export. The methodology helps researchers to learn about the highly different developmental paths that countries follow, and about the deepening international competition between countries such as the U.S. and China.

      At other times, Kim has analyzed who is influencing trade policy. His paper “Mapping Political Communities,” from the journal Political Analysis in 2021, looks at the U.S. Congress and uses mandatory reports filed by lobbyists to build a picture of which interests groups are most closely connected to which politicians.

      Kim has published all his papers while balancing both his scholarly research and the public launch of LobbyView, which occurred in 2018. He was awarded tenure by MIT in the spring of 2022. Currently he is an associate professor in the Department of Political Science and a faculty affiliate of the Institute for Data, Systems, and Society.

      By the book

      Kim has continued to explore firm-level lobbying dynamics, although his recent research runs in a few directions. In a 2021 working paper, Kim and co-author Federico Huneeus of the Central Bank of Chile built a model estimating that eliminating lobbying in the U.S. could increase productivity by as much as 6 percent.

      “Political rents [favorable policies] given to particular companies might introduce inefficiencies or a misallocation of resources in the economy,” Kim says. “You could allocate those resources to more productive although politically inactive firms, but now they’re given to less productive and yet politically active big companies, increasing market concentration and monopolies.”

      Kim is on sabbatical during the 2022-23 academic year, working on a book about the importance of firms’ political activities in trade policymaking. The book will have an expansive timeframe, dating back to ancient times, which underscores the salience of trade policy across eras. At the same time, the book will analyze the distinctive features of modern trade politics with deepening global production networks.

      “I’m trying to allow people to learn about the history of trade politics, to show how the politics have changed over time,” Kim says. “In doing that, I’m also highlighting the importance of firm-to-firm trade and the emergence of new trade coalitions among firms in different countries and industries that are linked through the global production chain.”

      While continuing his own scholarly research, Kim still leads LobbyView, which he views both as a big data resource for any scholars interested in money in politics and an excellent teaching resource for his MIT classes, as students can tap into it for projects and papers. LobbyView contains so much data, in fact, that part of the challenge is finding ways to mine it effectively.

      “It really offers me an opportunity to work with MIT students,” Kim says of LobbyView. “What I think I can contribute is to bring those technologies to our understanding of politics. Having this unique data set can really allow students here to use technology to learn about politics, and I believe that fits the MIT identity.” More

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      Helping the cause of environmental resilience

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      Haruko Wainwright, the Norman C. Rasmussen Career Development Professor in Nuclear Science and Engineering (NSE) and assistant professor in civil and environmental engineering at MIT, grew up in rural Japan, where many nuclear facilities are located. She remembers worrying about the facilities as a child. Wainwright was only 6 at the time of the Chernobyl accident in 1986, but still recollects it vividly.

      Those early memories have contributed to Wainwright’s determination to research how technologies can mold environmental resilience — the capability of mitigating the consequences of accidents and recovering from contamination.

      Wainwright believes that environmental monitoring can help improve resilience. She co-leads the U.S. Department of Energy (DOE)’s Advanced Long-term Environmental Monitoring Systems (ALTEMIS) project, which integrates technologies such as in situ sensors, geophysics, remote sensing, simulations, and artificial intelligence to establish new paradigms for monitoring. The project focuses on soil and groundwater contamination at more than 100 U.S. sites that were used for nuclear weapons production.

      As part of this research, which was featured last year in Environmental Science & Technology Journal, Wainwright is working on a machine learning framework for improving environmental monitoring strategies. She hopes the ALTEMIS project will enable the rapid detection of anomalies while ensuring the stability of residual contamination and waste disposal facilities.

      Childhood in rural Japan

      Even as a child, Wainwright was interested in physics, history, and a variety of other subjects.

      But growing up in a rural area was not ideal for someone interested in STEM. There were no engineers or scientists in the community and no science museums, either. “It was not so cool to be interested in science, and I never talked about my interest with anyone,” Wainwright recalls.

      Television and books were the only door to the world of science. “I did not study English until middle school and I had never been on a plane until college. I sometimes find it miraculous that I am now working in the U.S. and teaching at MIT,” she says.

      As she grew a little older, Wainwright heard a lot of discussions about nuclear facilities in the region and many stories about Hiroshima and Nagasaki.

      At the same time, giants like Marie Curie inspired her to pursue science. Nuclear physics was particularly fascinating. “At some point during high school, I started wondering ‘what are radiations, what is radioactivity, what is light,’” she recalls. Reading Richard Feynman’s books and trying to understand quantum mechanics made her want to study physics in college.

      Pursuing research in the United States

      Wainwright pursued an undergraduate degree in engineering physics at Kyoto University. After two research internships in the United States, Wainwright was impressed by the dynamic and fast-paced research environment in the country.

      And compared to Japan, there were “more women in science and engineering,” Wainwright says. She enrolled at the University of California at Berkeley in 2005, where she completed her doctorate in nuclear engineering with minors in statistics and civil and environmental engineering.

      Before moving to MIT NSE in 2022, Wainwright was a staff scientist in the Earth and Environmental Area at Lawrence Berkeley National Laboratory (LBNL). She worked on a variety of topics, including radioactive contamination, climate science, CO2 sequestration, precision agriculture, and watershed science. Her time at LBNL helped Wainwright build a solid foundation about a variety of environmental sensors and monitoring and simulation methods across different earth science disciplines.   

      Empowering communities through monitoring

      One of the most compelling takeaways from Wainwright’s early research: People trust actual measurements and data as facts, even though they are skeptical about models and predictions. “I talked with many people living in Fukushima prefecture. Many of them have dosimeters and measure radiation levels on their own. They might not trust the government, but they trust their own data and are then convinced that it is safe to live there and to eat local food,” Wainwright says.

      She has been impressed that area citizens have gained significant knowledge about radiation and radioactivity through these efforts. “But they are often frustrated that people living far away, in cities like Tokyo, still avoid agricultural products from Fukushima,” Wainwright says.

      Wainwright thinks that data derived from environmental monitoring — through proper visualization and communication — can address misconceptions and fake news that often hurt people near contaminated sites.

      Wainwright is now interested in how these technologies — tested with real data at contaminated sites — can be proactively used for existing and future nuclear facilities “before contamination happens,” as she explored for Nuclear News. “I don’t think it is a good idea to simply dismiss someone’s concern as irrational. Showing credible data has been much more effective to provide assurance. Or a proper monitoring network would enable us to minimize contamination or support emergency responses when accidents happen,” she says.

      Educating communities and students

      Part of empowering communities involves improving their ability to process science-based information. “Potentially hazardous facilities always end up in rural regions; minorities’ concerns are often ignored. The problem is that these regions don’t produce so many scientists or policymakers; they don’t have a voice,” Wainwright says, “I am determined to dedicate my time to improve STEM education in rural regions and to increase the voice in these regions.”

      In a project funded by DOE, she collaborates with the team of researchers at the University of Alaska — the Alaska Center for Energy and Power and Teaching Through Technology program — aiming to improve STEM education for rural and indigenous communities. “Alaska is an important place for energy transition and environmental justice,” Wainwright says. Micro-nuclear reactors can potentially improve the life of rural communities who bear the brunt of the high cost of fuel and transportation. However, there is a distrust of nuclear technologies, stemming from past nuclear weapon testing. At the same time, Alaska has vast metal mining resources for renewable energy and batteries. And there are concerns about environmental contamination from mining and various sources. The teams’ vision is much broader, she points out. “The focus is on broader environmental monitoring technologies and relevant STEM education, addressing general water and air qualities,” Wainwright says.

      The issues also weave into the courses Wainwright teaches at MIT. “I think it is important for engineering students to be aware of environmental justice related to energy waste and mining as well as past contamination events and their recovery,” she says. “It is not OK just to send waste to, or develop mines in, rural regions, which could be a special place for some people. We need to make sure that these developments will not harm the environment and health of local communities.” Wainwright also hopes that this knowledge will ultimately encourage students to think creatively about engineering designs that minimize waste or recycle material.

      The last question of the final quiz of one of her recent courses was: Assume that you store high-level radioactive waste in your “backyard.” What technical strategies would make you and your family feel safe? “All students thought about this question seriously and many suggested excellent points, including those addressing environmental monitoring,” Wainwright says, “that made me hopeful about the future.” More

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      Research, education, and connection in the face of war

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      When Russian forces invaded Ukraine in February 2022, Tetiana Herasymova had several decisions to make: What should she do, where should she live, and should she take her MITx MicroMasters capstone exams? She had registered for the Statistics and Data Science Program’s final exams just days prior to moving out of her apartment and into a bomb shelter. Although it was difficult to focus on studying and preparations with air horns sounding overhead and uncertainty lingering around her, she was determined to try. “I wouldn’t let the aggressor in the war squash my dreams,” she says.

      A love of research and the desire to improve teaching 

      An early love of solving puzzles and problems for fun piqued Herasymova’s initial interest in mathematics. When she later pursued her PhD in mathematics at Kiev National Taras Shevchenko University, Herasymova’s love of math evolved into a love of research. Throughout Herasymova’s career, she’s worked to close the gap between scientific researchers and educators. Starting as a math tutor at MBA Strategy, a company that prepares Ukrainian leaders for qualifying standardized tests for MBA programs, she was later promoted as the head of their test preparation department. Afterward, she moved on to an equivalent position at ZNOUA, a new project that prepared high school students for Ukraine’s standardized test, and she eventually became ZNOUA’s CEO.

      In 2018, she founded Prosteer, a “self-learning community” of educators who share research, pedagogy, and experience to learn from one another. “It’s really interesting to have a community of teachers from different domains,” she says, speaking of educators and researchers whose specialties range across language, mathematics, physics, music, and more.

      Implementing new pedagogical research in the classroom is often up to educators who seek out studies on an individual basis, Herasymova has found. “Lots of scientists are not practitioners,” she says, and the reverse is also true. She only became more determined to build these connections once she was promoted to head of test preparation at MBA Strategy because she wanted to share more effective pedagogy with the tutors she was mentoring.

      First, Herasymova knew she needed a way to measure the teachers’ effectiveness. She was able to determine whether students who received the company’s tutoring services improved their scores. Moreover, Ukraine keeps an open-access database of national standardized test scores, so anyone could analyze the data in hopes of improving the level of education in the country. She says, “I could do some analytics because I am a mathematician, but I knew I could do much more with this data if I knew data science and machine learning knowledge.”

      That’s why Herasymova sought out the MITx MicroMasters Program in Statistics and Data Science offered by the MIT Institute for Data, Systems, and Society (IDSS). “I wanted to learn the fundamentals so I could join the Learning Analytics domain,” she says. She was looking for a comprehensive program that covered the foundations without being overly basic. “I had some knowledge from the ground, so I could see the deepness of that course,” she says. Because of her background as an instructional designer, she thought the MicroMasters curriculum was well-constructed, calling the variety of videos, practice problems, and homework assignments that encouraged learners to approach the course material in different ways, “a perfect experience.”

      Another benefit of the MicroMasters program was its online format. “I had my usual work, so it was impossible to study in a stationary way,” she says. She found the structure to be more flexible than other programs. “It’s really great that you can construct your course schedule your own way, especially with your own adult life,” she says.

      Determination and support in the midst of war

      When the war first forced Herasymova to flee her apartment, she had already registered to take the exams for her four courses. “It was quite hard to prepare for exams when you could hear explosions outside of the bomb shelter,” she says. She and other Ukranians were invited to postpone their exams until the following session, but the next available testing period wouldn’t be held until October. “It was a hard decision, but I had to allow myself to try,” she says. “For all people in Ukraine, when you don’t know if you’re going to live or die, you try to live in the now. You have to appreciate every moment and what life brings to you. You don’t say, ‘Someday’ — you do it today or tomorrow.”

      In addition to emotional support from her boyfriend, Herasymova had a group of friends who had also enrolled in the program, and they supported each other through study sessions and an ongoing chat. Herasymova’s personal support network helped her accomplish what she set out to do with her MicroMasters program, and in turn, she was able to support her professional network. While Prosteer halted its regular work during the early stages of the war, Herasymova was determined to support the community of educators and scientists that she had built. They continued meeting weekly to exchange ideas as usual. “It’s intrinsic motivation,” she says. They managed to restore all of their activities by October.

      Despite the factors stacked against her, Herasymova’s determination paid off — she passed all of her exams in May, the final step to earning her MicroMasters certificate in statistics and data science. “I just couldn’t believe it,” she says. “It was definitely a bifurcation point. The moment when you realize that you have something to rely on, and that life is just beginning to show all its diversity despite the fact that you live in war.” With her newly minted certificate in hand, Herasymova has continued her research on the effectiveness of educational models — analyzing the data herself — with a summer research program at New York University. 

      The student becomes the master

      After moving seven times between February and October, heading west from Kyiv until most recently settling near the border of Poland, Herasymova hopes she’s moved for the last time. Ukrainian Catholic University offered her a position teaching both mathematics and programming. Before enrolling in the MicroMasters Program in Statistics and Data Science, she had some prior knowledge of programming languages and mathematical algorithms, but she didn’t know Python. She took MITx’s Introduction to Computer Science and Programming Using Python to prepare. “It gave me a huge step forward,” she says. “I learned a lot. Now, not only can I work with Python machine learning models in programming language R, I also have knowledge of the big picture of the purpose and the point to do so.”

      In addition to the skills the MicroMasters Program trained her in, she gained firsthand experience in learning new subjects and exploring topics more deeply. She will be sharing that practice with the community of students and teachers she’s built, plus, she plans on guiding them through this course during the next year. As a continuation of her own educational growth, says she’s looking forward to her next MITx course this year, Data Analysis.

      Herasymova advises that the best way to keep progressing is investing a lot of time. “Adults don’t want to hear this, but you need one or two years,” she says. “Allow yourself to be stupid. If you’re an expert in one domain and want to switch to another, or if you want to understand something new, a lot of people don’t ask questions or don’t ask for help. But from this point, if I don’t know something, I know I should ask for help because that’s the start of learning. With a fixed mindset, you won’t grow.”

      July 2022 MicroMasters Program Joint Completion Celebration. Ukrainian student Tetiana Herasymova, who completed her program amid war in her home country, speaks at 43:55. More

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      Unpacking the “black box” to build better AI models

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      When deep learning models are deployed in the real world, perhaps to detect financial fraud from credit card activity or identify cancer in medical images, they are often able to outperform humans.

      But what exactly are these deep learning models learning? Does a model trained to spot skin cancer in clinical images, for example, actually learn the colors and textures of cancerous tissue, or is it flagging some other features or patterns?

      These powerful machine-learning models are typically based on artificial neural networks that can have millions of nodes that process data to make predictions. Due to their complexity, researchers often call these models “black boxes” because even the scientists who build them don’t understand everything that is going on under the hood.

      Stefanie Jegelka isn’t satisfied with that “black box” explanation. A newly tenured associate professor in the MIT Department of Electrical Engineering and Computer Science, Jegelka is digging deep into deep learning to understand what these models can learn and how they behave, and how to build certain prior information into these models.

      “At the end of the day, what a deep-learning model will learn depends on so many factors. But building an understanding that is relevant in practice will help us design better models, and also help us understand what is going on inside them so we know when we can deploy a model and when we can’t. That is critically important,” says Jegelka, who is also a member of the Computer Science and Artificial Intelligence Laboratory (CSAIL) and the Institute for Data, Systems, and Society (IDSS).

      Jegelka is particularly interested in optimizing machine-learning models when input data are in the form of graphs. Graph data pose specific challenges: For instance, information in the data consists of both information about individual nodes and edges, as well as the structure — what is connected to what. In addition, graphs have mathematical symmetries that need to be respected by the machine-learning model so that, for instance, the same graph always leads to the same prediction. Building such symmetries into a machine-learning model is usually not easy.

      Take molecules, for instance. Molecules can be represented as graphs, with vertices that correspond to atoms and edges that correspond to chemical bonds between them. Drug companies may want to use deep learning to rapidly predict the properties of many molecules, narrowing down the number they must physically test in the lab.

      Jegelka studies methods to build mathematical machine-learning models that can effectively take graph data as an input and output something else, in this case a prediction of a molecule’s chemical properties. This is particularly challenging since a molecule’s properties are determined not only by the atoms within it, but also by the connections between them.  

      Other examples of machine learning on graphs include traffic routing, chip design, and recommender systems.

      Designing these models is made even more difficult by the fact that data used to train them are often different from data the models see in practice. Perhaps the model was trained using small molecular graphs or traffic networks, but the graphs it sees once deployed are larger or more complex.

      In this case, what can researchers expect this model to learn, and will it still work in practice if the real-world data are different?

      “Your model is not going to be able to learn everything because of some hardness problems in computer science, but what you can learn and what you can’t learn depends on how you set the model up,” Jegelka says.

      She approaches this question by combining her passion for algorithms and discrete mathematics with her excitement for machine learning.

      From butterflies to bioinformatics

      Jegelka grew up in a small town in Germany and became interested in science when she was a high school student; a supportive teacher encouraged her to participate in an international science competition. She and her teammates from the U.S. and Singapore won an award for a website they created about butterflies, in three languages.

      “For our project, we took images of wings with a scanning electron microscope at a local university of applied sciences. I also got the opportunity to use a high-speed camera at Mercedes Benz — this camera usually filmed combustion engines — which I used to capture a slow-motion video of the movement of a butterfly’s wings. That was the first time I really got in touch with science and exploration,” she recalls.

      Intrigued by both biology and mathematics, Jegelka decided to study bioinformatics at the University of Tübingen and the University of Texas at Austin. She had a few opportunities to conduct research as an undergraduate, including an internship in computational neuroscience at Georgetown University, but wasn’t sure what career to follow.

      When she returned for her final year of college, Jegelka moved in with two roommates who were working as research assistants at the Max Planck Institute in Tübingen.

      “They were working on machine learning, and that sounded really cool to me. I had to write my bachelor’s thesis, so I asked at the institute if they had a project for me. I started working on machine learning at the Max Planck Institute and I loved it. I learned so much there, and it was a great place for research,” she says.

      She stayed on at the Max Planck Institute to complete a master’s thesis, and then embarked on a PhD in machine learning at the Max Planck Institute and the Swiss Federal Institute of Technology.

      During her PhD, she explored how concepts from discrete mathematics can help improve machine-learning techniques.

      Teaching models to learn

      The more Jegelka learned about machine learning, the more intrigued she became by the challenges of understanding how models behave, and how to steer this behavior.

      “You can do so much with machine learning, but only if you have the right model and data. It is not just a black-box thing where you throw it at the data and it works. You actually have to think about it, its properties, and what you want the model to learn and do,” she says.

      After completing a postdoc at the University of California at Berkeley, Jegelka was hooked on research and decided to pursue a career in academia. She joined the faculty at MIT in 2015 as an assistant professor.

      “What I really loved about MIT, from the very beginning, was that the people really care deeply about research and creativity. That is what I appreciate the most about MIT. The people here really value originality and depth in research,” she says.

      That focus on creativity has enabled Jegelka to explore a broad range of topics.

      In collaboration with other faculty at MIT, she studies machine-learning applications in biology, imaging, computer vision, and materials science.

      But what really drives Jegelka is probing the fundamentals of machine learning, and most recently, the issue of robustness. Often, a model performs well on training data, but its performance deteriorates when it is deployed on slightly different data. Building prior knowledge into a model can make it more reliable, but understanding what information the model needs to be successful and how to build it in is not so simple, she says.

      She is also exploring methods to improve the performance of machine-learning models for image classification.

      Image classification models are everywhere, from the facial recognition systems on mobile phones to tools that identify fake accounts on social media. These models need massive amounts of data for training, but since it is expensive for humans to hand-label millions of images, researchers often use unlabeled datasets to pretrain models instead.

      These models then reuse the representations they have learned when they are fine-tuned later for a specific task.

      Ideally, researchers want the model to learn as much as it can during pretraining, so it can apply that knowledge to its downstream task. But in practice, these models often learn only a few simple correlations — like that one image has sunshine and one has shade — and use these “shortcuts” to classify images.

      “We showed that this is a problem in ‘contrastive learning,’ which is a standard technique for pre-training, both theoretically and empirically. But we also show that you can influence the kinds of information the model will learn to represent by modifying the types of data you show the model. This is one step toward understanding what models are actually going to do in practice,” she says.

      Researchers still don’t understand everything that goes on inside a deep-learning model, or details about how they can influence what a model learns and how it behaves, but Jegelka looks forward to continue exploring these topics.

      “Often in machine learning, we see something happen in practice and we try to understand it theoretically. This is a huge challenge. You want to build an understanding that matches what you see in practice, so that you can do better. We are still just at the beginning of understanding this,” she says.

      Outside the lab, Jegelka is a fan of music, art, traveling, and cycling. But these days, she enjoys spending most of her free time with her preschool-aged daughter. More

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      in Data Management & Statistics

      Urbanization: No fast lane to transformation

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      Accra, Ghana, “is a city I’ve come to know as well as any place in the U.S,” says Associate Professor Noah Nathan, who has conducted research there over the past 15 years. The booming capital of 4 million is an ideal laboratory for investigating the rapid urbanization of nations in Africa and beyond, believes Nathan, who joined the MIT Department of Political Science in July.

      “Accra is vibrant and exciting, with gleaming glass office buildings, shopping centers, and an emerging middle class,” he says. “But at the same time there is enormous poverty, with slums and a mixing pot of ethnic groups.” Cities like Accra that have emerged in developing countries around the world are “hybrid spaces” that provoke a multitude of questions for Nathan.

      “Rich and poor are in incredibly close proximity and I want to know how this dramatic inequality can be sustainable, and what politics looks like with such ethnic and class diversity living side-by-side,” he says.

      With his singular approach to data collection and deep understanding of Accra, its neighborhoods, and increasingly, its built environment, Nathan is generating a body of scholarship on the political impacts of urbanization throughout the global South.

      A trap in the urban transition

      Nathan’s early studies of Accra challenged common expectations about how urbanization shifts political behavior.

      “Modernization theory states that as people become more ‘modern’ and move to cities, ethnicity fades and class becomes the dominant dynamic in political behavior,” explains Nathan. “It predicts that the process of urbanization transforms the relationship between politicians and voters, and elections become more ideologically and policy oriented,” says Nathan.  

      But in Accra, the heart of one of the fastest-growing economies in the developing world, Nathan found “a type of politics stuck in an old equilibrium, hard to dislodge, and not updated by newly wealthy voters,” he says. Using census data revealing the demographic composition of every neighborhood in Accra, Nathan determined that there were many enclaves in which forms of patronage politics and ethnic competition persist. He conducted sample surveys and collected polling-station level results on residents’ voting across the city. “I was able to merge spatial data on where people lived and their answers to survey questions, and determine how different neighborhoods voted,” says Nathan.

      Among his findings: Ethnic politics were thriving in many parts of Accra, and many middle-class voters were withdrawing from politics entirely in reaction to the well-established practice of patronage rather than pressuring politicians to change their approach. “They decided it was better to look out for themselves,” he explains.

      In Nathan’s 2019 book, “Electoral Politics and Africa’s Urban Transition: Class and Ethnicity in Ghana,” he described this situation as a trap. “As the wealthy exit from the state, politicians double down on patronage politics with poor voters, which the middle class views as further evidence of corruption,” he explains. The wealthier citizens “want more public goods, and big policy reforms, such as changes in the health-care and tax systems, while poor voters focus on immediate needs such as jobs, homes, better schools in their communities.”

      In Ghana and other developing countries where the state’s capacity is limited, politicians can’t deliver on the broad-scale changes desired by the middle class. Motivated by their own political survival, they continue dealing with poor voters as clients, trading services for votes. “I connect urban politics in Ghana to the early 20th-century urban machines in the United States, run by party bosses,” says Nathan.

      This may prove sobering news for many engaged with the developing world. “There’s enormous enthusiasm among foreign aid organizations, in the popular press and policy circles, for the idea that urbanization will usher in big, radical political change,” notes Nathan. “But these kinds of transformations will only come about with structural change such as civil service reforms and nonpartisan welfare programs that can push politicians beyond just delivering targeted services to poor voters.”

      Falling in love with Ghana

      For most of his youth, Nathan was a committed jazz saxophonist, toying with going professional. But he had long cultivated another fascination as well. “I was a huge fan of ‘The West Wing’ in middle school” and got into American politics through that,” he says. He volunteered in Hillary Clinton’s 2008 primary campaign during college, but soon realized work in politics was “both more boring and not as idealistic” as he’d hoped.

      As an undergraduate at Harvard University, where he concentrated in government, he “signed up for African history on a lark — because American high schools didn’t teach anything on the subject — and I loved it,” Nathan says. He took another African history course, and then found his way to classes taught by Harvard political scientist Robert H. Bates PhD ’69 that focused on the political economy of development, ethnic conflict, and state failure in Africa. In the summer before his senior year, he served as a research assistant for one of his professors in Ghana, and then stayed longer, hoping to map out a senior thesis on ethnic conflict.

      “Once I got to Ghana, I was fascinated by the place — the dynamism of this rapidly transforming society,” he recalls. “Growing up in the U.S., there are a lot of stereotypes about the developing world, and I quickly realized how much more complicated everything is.”

      These initial experiences living in Ghana shaped Nathan’s ideas for what became his doctoral dissertation at Harvard and first book on the ethnic and class dynamics driving the nation’s politics. His frequent return visits to that country sparked a wealth of research that built on and branched out from this work.

      One set of studies examines the historical development of Ghana’s rural north in its colonial and post-colonial periods, the center of ethnic conflict in the 1990s. These are communities “where the state delivers few resources, doesn’t seem to do much, yet figures as a central actor in people’s lives,” he says.

      Part of this region had been a German colony, and the other part was originally under British rule, and Nathan compared the political trajectories of these two areas, focusing on differences in early state efforts to impose new forms of local political leadership and gradually build a formal education system.

      “The colonial legacy in the British areas was elite families who came to dominate, entrenching themselves and creating political dynasties and economic inequality,” says Nathan. But similar ethnic groups exposed to different state policies in the original German colony were not riven with the same class inequalities, and enjoy better access to government services today. “This research is changing how we think about state weakness in the developing world, how we tend to see the emergence of inequality where societal elites come into power,” he says. The results of Nathan’s research will be published in a forthcoming book, “The Scarce State: Inequality and Political Power in the Hinterland.”

      Politics of built spaces

      At MIT, Nathan is pivoting to a fresh new framing for questions on urbanization. Wielding a public source map of cities around the world, he is scrutinizing the geometry of street grids in 1,000 of sub-Saharan Africa’s largest cities “to think about urban order,” he says. Digitizing historical street maps of African cities from the Library of Congress’s map collection, he can look at how these cities were built and evolved physically. “When cities emerge based on grids, rather than tangles, they are more legible to governments,” he says. “This means that it’s easier to find people, easier to govern, tax, repress, and politically mobilize them.”  

      Nathan has begun to demonstrate that in the post-colonial period, “cities that were built under authoritarian regimes tend to be most legible, with even low-capacity regimes trying to impose control and make them gridded.” Democratic governments, he says, “lead to more tangled and chaotic built environments, with people doing what they want.” He also draws comparisons to how state policies shaped urban growth in the United States, with local and federal governments exerting control over neighborhood development, leading to redlining and segregation in many cities.

      Nathan’s interests naturally pull him toward the MIT Governance Lab and Global Diversity Lab. “I’m hoping to dive into both,” he says. “One big attraction of the department is the really interesting research that’s being done on developing countries.”  He also plans to use the stature he has built over many years of research in Africa to help “open doors” to African researchers and students, who may not always get the same kind of access to institutions and data that he has had. “I’m hoping to build connections to researchers in the global South,” he says. More

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      in Data Management & Statistics

      Making each vote count

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      Graduate student Jacob Jaffe wants to improve the administration of American elections. To do that, he is posing “questions in political science that we haven’t been asking enough,” he says, “and solving them with methods we haven’t been using enough.”

      Considerable research has been devoted to understanding “who votes, and what makes people vote or not vote,” says Jaffe. He is training his attention on questions of a different nature: Does providing practical information to voters about how to cast their ballots change how they will vote? Is it possible to increase the accuracy of vote-counting, on a state-by-state and even precinct-by-precinct basis? How do voters experience polling places? These problems form the core of his dissertation.

      Taking advantage of the resources at the MIT Election Data and Science Lab, where he serves as a researcher, Jaffe conducts novel field experiments to gather highly detailed information on local, state, and federal elections, and analyzes this trove with advanced statistical techniques. Whether investigating the probability of miscounts in voting, or the possibility of changing a voter’s mode of voting, Jaffe intends to strengthen the scaffolding that supports representative government. “Elections are both theoretically and normatively important; they’re the basis of our belief in the moral rightness of the state to do the things the state does,” he says.

      Click this link

      For one of his keystone projects, Jaffe seized a unique opportunity to run a big field experiment. In summer 2020, at the height of the Covid-19 pandemic, he emailed 80,000 Floridians instructions on how to vote in an upcoming primary by mail. His email contained a link enabling recipients to fill out two simple questions to receive a ballot. “I wanted to learn if this was an effective method for getting people to vote by mail, and I proved it is, statistically,” he says. “This is important to know because if elections are held in times when we might need people to vote nonlocally or vote using one method over another — if they’re displaced by a hurricane or another emergency, for instance — I learned that we can effect a new vote mode practically and quickly.”

      One of Jaffe’s insights from this experiment is that “people do read their voting-related emails, but the content of the email has to be something they can act on proximately,” he says. “A message reminding them to vote two weeks from now is not so helpful.” The lower the burden on an individual to participate in voting, whether due to proximity to a polling site or instructions on how to receive and cast a ballot, the greater the likelihood of that person engaging in the election.

      “If we want people to vote by mail, we need to reduce the informational cost so it’s easier for voters to understand how the system works,” he says.

      Another significant research thrust for Jaffe involves scrutinizing accuracy in vote counting, using instances of recounts in presidential elections. Ensuring each vote counts, he says, “is one of the most fundamental questions in democracy,” he says.

      With access to 20 elections in 2020, Jaffe is comparing original vote totals for each candidate to the recounted, correct tally, on a precinct-level basis. “Using original combinatorial techniques, I can estimate the probability of miscounting ballots,” he says. The ultimate goal is to generate a granular picture of the efficacy of election administration across the country.

      “It varies a lot by state, and most states do a good job,” he says. States that take their time in counting perform better. “There’s a phenomenon where some towns race to get results in as quickly as possible, and this affects their accuracy.”

      In spite of the bright spots, Jaffe sees chronic underfunding of American elections. “We need to give local administrators the resources, the time and money to fund employees to do their jobs,” he says. The worse the situation is, “the more likely that elections will be called wrong, with no one knowing.” Jaffe believes that his analysis can offer states useful information for improving election administration. “Determining how good a place is historically at counting ballots can help determine the likelihood of needing costly recounts in future elections,” he says.

      The ballot box and beyond

      It didn’t take Jaffe long to decide on a life dedicated to studying politics. Part of a Boston-area family who, he says, “liked discussing what was going on in the world,” he had his own subscriptions to Time magazine at age 9, and to The Economist in middle school. During high school, he volunteered for then-Massachusetts Representative Barney Frank and Senator John Kerry, working on constituent services. At Rice University, he interned all four years with political scientist Robert M. Stein, an expert on voting and elections. With Stein’s help, Jaffe landed a position the summer before his senior year with the Department of Justice (DOJ), researching voting rights cases.

      “The experience was fascinating, and the work felt super important,” says Jaffe. His portfolio involved determining whether legal challenges to particular elections met the statistical standard for racial gerrymandering. “I had to answer hard quantitative questions about the relationship between race and voting in an area, and whether minority candidates were systematically prevented from winning,” he says.

      But while Jaffe cared a lot about this work, he didn’t feel adequately challenged. “As a 21-year-old at DOJ, I learned that I could address problems in the world using statistics,” he says. “But I felt I could have a greater impact addressing tougher questions outside of voting rights.”

      Jaffe was drawn to political science at MIT, and specifically to the research of Charles Stewart III, the Kenan Sahin Distinguished Professor of Political Science, director of the MIT Election Lab, and head of Jaffe’s thesis committee. It wasn’t just the opportunity to plumb the lab’s singular repository of voting data that attracted Jaffe, but its commitment to making every vote count. For Jaffe, this was a call to arms to investigate the many, and sometimes quotidian, obstacles, between citizens and ballot boxes.

      To this end, he has been analyzing, with the help of mathematical methods from queuing theory, why some elections involve wait lines of six hours and longer at polling sites. “We know that simpler ballots mean people move don’t get stuck in these lines, where they might potentially give up before voting,” he says. “Looking at the content of ballots and the interval between voter check-in and check-out, I learned that adding races, rather than candidates, to a ballot, means that people take more time completing ballots, leading to interminable lines.”

      A key takeaway from his ensemble of studies is that “while it’s relatively rare that elections are bad, we shouldn’t think that we’re good to go,” he says. “Instead, we need to be asking under what conditions do things get bad, and how can we make them better.” More

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      in Data Management & Statistics

      Investigating at the interface of data science and computing

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      A visual model of Guy Bresler’s research would probably look something like a Venn diagram. He works at the four-way intersection where theoretical computer science, statistics, probability, and information theory collide.

      “There are always new things to do be done at the interface. There are always opportunities for entirely new questions to ask,” says Bresler, an associate professor who recently earned tenure in MIT’s Department of Electrical Engineering and Computer Science (EECS).

      A theoretician, he aims to understand the delicate interplay between structure in data, the complexity of models, and the amount of computation needed to learn those models. Recently, his biggest focus has been trying to unveil fundamental phenomena that are broadly responsible for determining the computational complexity of statistics problems — and finding the “sweet spot” where available data and computation resources enable researchers to effectively solve a problem.

      When trying to solve a complex statistics problem, there is often a tug-of-war between data and computation. Without enough data, the computation needed to solve a statistical problem can be intractable, or at least consume a staggering amount of resources. But get just enough data and suddenly the intractable becomes solvable; the amount of computation needed to come up with a solution drops dramatically.

      The majority of modern statistical problems exhibits this sort of trade-off between computation and data, with applications ranging from drug development to weather prediction. Another well-studied and practically important example is cryo-electron microscopy, Bresler says. With this technique, researchers use an electron microscope to take images of molecules in different orientations. The central challenge is how to solve the inverse problem — determining the molecule’s structure given the noisy data. Many statistical problems can be formulated as inverse problems of this sort.

      One aim of Bresler’s work is to elucidate relationships between the wide variety of different statistics problems currently being studied. The dream is to classify statistical problems into equivalence classes, as has been done for other types of computational problems in the field of computational complexity. Showing these sorts of relationships means that, instead of trying to understand each problem in isolation, researchers can transfer their understanding from a well-studied problem to a poorly understood one, he says.

      Adopting a theoretical approach

      For Bresler, a desire to theoretically understand various basic phenomena inspired him to follow a path into academia.

      Both of his parents worked as professors and showed how fulfilling academia can be, he says. His earliest introduction to the theoretical side of engineering came from his father, who is an electrical engineer and theoretician studying signal processing. Bresler was inspired by his work from an early age. As an undergraduate at the University of Illinois at Urbana-Champaign, he bounced between physics, math, and computer science courses. But no matter the topic, he gravitated toward the theoretical viewpoint.

      In graduate school at the University of California at Berkeley, Bresler enjoyed the opportunity to work in a wide variety of topics spanning probability, theoretical computer science, and mathematics. His driving motivator was a love of learning new things.

      “Working at the interface of multiple fields with new questions, there is a feeling that one had better learn as much as possible if one is to have any chance of finding the right tools to answer those questions,” he says.

      That curiosity led him to MIT for a postdoc in the Laboratory for Information and Decision Systems (LIDS) in 2013, and then he joined the faculty two years later as an assistant professor in EECS. He was named an associate professor in 2019.

      Bresler says he was drawn to the intellectual atmosphere at MIT, as well as the supportive environment for launching bold research quests and trying to make progress in new areas of study.

      Opportunities for collaboration

      “What really struck me was how vibrant and energetic and collaborative MIT is. I have this mental list of more than 20 people here who I would love to have lunch with every single week and collaborate with on research. So just based on sheer numbers, joining MIT was a clear win,” he says.

      He’s especially enjoyed collaborating with his students, who continually teach him new things and ask deep questions that drive exciting research projects. One such student, Matthew Brennan, who was one of Bresler’s closest collaborators, tragically and unexpectedly passed away in January, 2021.

      The shock from Brennan’s death is still raw for Bresler, and it derailed his research for a time.

      “Beyond his own prodigious capabilities and creativity, he had this amazing ability to listen to an idea of mine that was almost completely wrong, extract from it a useful piece, and then pass the ball back,” he says. “We had the same vision for what we wanted to achieve in the work, and we were driven to try to tell a certain story. At the time, almost nobody was pursuing this particular line of work, and it was in a way kind of lonely. But he trusted me, and we encouraged one another to keep at it when things seemed bleak.”

      Those lessons in perseverance fuel Bresler as he and his students continue exploring questions that, by their nature, are difficult to answer.

      One area he’s worked in on-and-off for over a decade involves learning graphical models from data. Models of certain types of data, such as time-series data consisting of temperature readings, are often constructed by domain experts who have relevant knowledge and can build a reasonable model, he explains.

      But for many types of data with complex dependencies, such as social network or biological data, it is not at all clear what structure a model should take. Bresler’s work seeks to estimate a structured model from data, which could then be used for downstream applications like making recommendations or better predicting the weather.

      The basic question of identifying good models, whether algorithmically in a complex setting or analytically, by specifying a useful toy model for theoretical analysis, connects the abstract work with engineering practice, he says.

      “In general, modeling is an art. Real life is complicated and if you write down some super-complicated model that tries to capture every feature of a problem, it is doomed,” says Bresler. “You have to think about the problem and understand the practical side of things on some level to identify the correct features of the problem to be modeled, so that you can hope to actually solve it and gain insight into what one should do in practice.”

      Outside the lab, Bresler often finds himself solving very different kinds of problems. He is an avid rock climber and spends much of his free time bouldering throughout New England.

      “I really love it. It is a good excuse to get outside and get sucked into a whole different world. Even though there is problem solving involved, and there are similarities at the philosophical level, it is totally orthogonal to sitting down and doing math,” he says. More