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    Investigating at the interface of data science and computing

    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

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    Neurodegenerative disease can progress in newly identified patterns

    Neurodegenerative diseases — like amyotrophic lateral sclerosis (ALS, or Lou Gehrig’s disease), Alzheimer’s, and Parkinson’s — are complicated, chronic ailments that can present with a variety of symptoms, worsen at different rates, and have many underlying genetic and environmental causes, some of which are unknown. ALS, in particular, affects voluntary muscle movement and is always fatal, but while most people survive for only a few years after diagnosis, others live with the disease for decades. Manifestations of ALS can also vary significantly; often slower disease development correlates with onset in the limbs and affecting fine motor skills, while the more serious, bulbar ALS impacts swallowing, speaking, breathing, and mobility. Therefore, understanding the progression of diseases like ALS is critical to enrollment in clinical trials, analysis of potential interventions, and discovery of root causes.

    However, assessing disease evolution is far from straightforward. Current clinical studies typically assume that health declines on a downward linear trajectory on a symptom rating scale, and use these linear models to evaluate whether drugs are slowing disease progression. However, data indicate that ALS often follows nonlinear trajectories, with periods where symptoms are stable alternating with periods when they are rapidly changing. Since data can be sparse, and health assessments often rely on subjective rating metrics measured at uneven time intervals, comparisons across patient populations are difficult. These heterogenous data and progression, in turn, complicate analyses of invention effectiveness and potentially mask disease origin.

    Now, a new machine-learning method developed by researchers from MIT, IBM Research, and elsewhere aims to better characterize ALS disease progression patterns to inform clinical trial design.

    “There are groups of individuals that share progression patterns. For example, some seem to have really fast-progressing ALS and others that have slow-progressing ALS that varies over time,” says Divya Ramamoorthy PhD ’22, a research specialist at MIT and lead author of a new paper on the work that was published this month in Nature Computational Science. “The question we were asking is: can we use machine learning to identify if, and to what extent, those types of consistent patterns across individuals exist?”

    Their technique, indeed, identified discrete and robust clinical patterns in ALS progression, many of which are non-linear. Further, these disease progression subtypes were consistent across patient populations and disease metrics. The team additionally found that their method can be applied to Alzheimer’s and Parkinson’s diseases as well.

    Joining Ramamoorthy on the paper are MIT-IBM Watson AI Lab members Ernest Fraenkel, a professor in the MIT Department of Biological Engineering; Research Scientist Soumya Ghosh of IBM Research; and Principal Research Scientist Kenney Ng, also of IBM Research. Additional authors include Kristen Severson PhD ’18, a senior researcher at Microsoft Research and former member of the Watson Lab and of IBM Research; Karen Sachs PhD ’06 of Next Generation Analytics; a team of researchers with Answer ALS; Jonathan D. Glass and Christina N. Fournier of the Emory University School of Medicine; the Pooled Resource Open-Access ALS Clinical Trials Consortium; ALS/MND Natural History Consortium; Todd M. Herrington of Massachusetts General Hospital (MGH) and Harvard Medical School; and James D. Berry of MGH.

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    MIT Professor Ernest Fraenkel describes early stages of his research looking at root causes of amyotrophic lateral sclerosis (ALS).

    Reshaping health decline

    After consulting with clinicians, the team of machine learning researchers and neurologists let the data speak for itself. They designed an unsupervised machine-learning model that employed two methods: Gaussian process regression and Dirichlet process clustering. These inferred the health trajectories directly from patient data and automatically grouped similar trajectories together without prescribing the number of clusters or the shape of the curves, forming ALS progression “subtypes.” Their method incorporated prior clinical knowledge in the way of a bias for negative trajectories — consistent with expectations for neurodegenerative disease progressions — but did not assume any linearity. “We know that linearity is not reflective of what’s actually observed,” says Ng. “The methods and models that we use here were more flexible, in the sense that, they capture what was seen in the data,” without the need for expensive labeled data and prescription of parameters.

    Primarily, they applied the model to five longitudinal datasets from ALS clinical trials and observational studies. These used the gold standard to measure symptom development: the ALS functional rating scale revised (ALSFRS-R), which captures a global picture of patient neurological impairment but can be a bit of a “messy metric.” Additionally, performance on survivability probabilities, forced vital capacity (a measurement of respiratory function), and subscores of ALSFRS-R, which looks at individual bodily functions, were incorporated.

    New regimes of progression and utility

    When their population-level model was trained and tested on these metrics, four dominant patterns of disease popped out of the many trajectories — sigmoidal fast progression, stable slow progression, unstable slow progression, and unstable moderate progression — many with strong nonlinear characteristics. Notably, it captured trajectories where patients experienced a sudden loss of ability, called a functional cliff, which would significantly impact treatments, enrollment in clinical trials, and quality of life.

    The researchers compared their method against other commonly used linear and nonlinear approaches in the field to separate the contribution of clustering and linearity to the model’s accuracy. The new work outperformed them, even patient-specific models, and found that subtype patterns were consistent across measures. Impressively, when data were withheld, the model was able to interpolate missing values, and, critically, could forecast future health measures. The model could also be trained on one ALSFRS-R dataset and predict cluster membership in others, making it robust, generalizable, and accurate with scarce data. So long as 6-12 months of data were available, health trajectories could be inferred with higher confidence than conventional methods.

    The researchers’ approach also provided insights into Alzheimer’s and Parkinson’s diseases, both of which can have a range of symptom presentations and progression. For Alzheimer’s, the new technique could identify distinct disease patterns, in particular variations in the rates of conversion of mild to severe disease. The Parkinson’s analysis demonstrated a relationship between progression trajectories for off-medication scores and disease phenotypes, such as the tremor-dominant or postural instability/gait difficulty forms of Parkinson’s disease.

    The work makes significant strides to find the signal amongst the noise in the time-series of complex neurodegenerative disease. “The patterns that we see are reproducible across studies, which I don’t believe had been shown before, and that may have implications for how we subtype the [ALS] disease,” says Fraenkel. As the FDA has been considering the impact of non-linearity in clinical trial designs, the team notes that their work is particularly pertinent.

    As new ways to understand disease mechanisms come online, this model provides another tool to pick apart illnesses like ALS, Alzheimer’s, and Parkinson’s from a systems biology perspective.

    “We have a lot of molecular data from the same patients, and so our long-term goal is to see whether there are subtypes of the disease,” says Fraenkel, whose lab looks at cellular changes to understand the etiology of diseases and possible targets for cures. “One approach is to start with the symptoms … and see if people with different patterns of disease progression are also different at the molecular level. That might lead you to a therapy. Then there’s the bottom-up approach, where you start with the molecules” and try to reconstruct biological pathways that might be affected. “We’re going [to be tackling this] from both ends … and finding if something meets in the middle.”

    This research was supported, in part, by the MIT-IBM Watson AI Lab, the Muscular Dystrophy Association, Department of Veterans Affairs of Research and Development, the Department of Defense, NSF Gradate Research Fellowship Program, Siebel Scholars Fellowship, Answer ALS, the United States Army Medical Research Acquisition Activity, National Institutes of Health, and the NIH/NINDS. More

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    New program to support translational research in AI, data science, and machine learning

    The MIT School of Engineering and Pillar VC today announced the MIT-Pillar AI Collective, a one-year pilot program funded by a gift from Pillar VC that will provide seed grants for projects in artificial intelligence, machine learning, and data science with the goal of supporting translational research. The program will support graduate students and postdocs through access to funding, mentorship, and customer discovery.

    Administered by the MIT Deshpande Center for Technological Innovation, the MIT-Pillar AI Collective will center on the market discovery process, advancing projects through market research, customer discovery, and prototyping. Graduate students and postdocs will aim to emerge from the program having built minimum viable products, with support from Pillar VC and experienced industry leaders.

    “We are grateful for this support from Pillar VC and to join forces to converge the commercialization of translational research in AI, data science, and machine learning, with an emphasis on identifying and cultivating prospective entrepreneurs,” says Anantha Chandrakasan, dean of the MIT School of Engineering and Vannevar Bush Professor of Electrical Engineering and Computer Science. “Pillar’s focus on mentorship for our graduate students and postdoctoral researchers, and centering the program within the Deshpande Center, will undoubtedly foster big ideas in AI and create an environment for prospective companies to launch and thrive.” 

    Founded by Jamie Goldstein ’89, Pillar VC is committed to growing companies and investing in personal and professional development, coaching, and community.

    “Many of the most promising companies of the future are living at MIT in the form of transformational research in the fields of data science, AI, and machine learning,” says Goldstein. “We’re honored by the chance to help unlock this potential and catalyze a new generation of founders by surrounding students and postdoctoral researchers with the resources and mentorship they need to move from the lab to industry.”

    The program will launch with the 2022-23 academic year. Grants will be open only to MIT faculty and students, with an emphasis on funding for graduate students in their final year, as well as postdocs. Applications must be submitted by MIT employees with principal investigator status. A selection committee composed of three MIT representatives will include Devavrat Shah, faculty director of the Deshpande Center, the Andrew (1956) and Erna Viterbi Professor in the Department of Electrical Engineering and Computer Science and the Institute for Data, Systems, and Society; the chair of the selection committee; and a representative from the MIT Schwarzman College of Computing. The committee will also include representation from Pillar VC. Funding will be provided for up to nine research teams.

    “The Deshpande Center will serve as the perfect home for the new collective, given its focus on moving innovative technologies from the lab to the marketplace in the form of breakthrough products and new companies,” adds Chandrakasan. 

    “The Deshpande Center has a 20-year history of guiding new technologies toward commercialization, where they can have a greater impact,” says Shah. “This new collective will help the center expand its own impact by helping more projects realize their market potential and providing more support to researchers in the fast-growing fields of AI, machine learning, and data science.” More

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    Q&A: Global challenges surrounding the deployment of AI

    The AI Policy Forum (AIPF) is an initiative of the MIT Schwarzman College of Computing to move the global conversation about the impact of artificial intelligence from principles to practical policy implementation. Formed in late 2020, AIPF brings together leaders in government, business, and academia to develop approaches to address the societal challenges posed by the rapid advances and increasing applicability of AI.

    The co-chairs of the AI Policy Forum are Aleksander Madry, the Cadence Design Systems Professor; Asu Ozdaglar, deputy dean of academics for the MIT Schwarzman College of Computing and head of the Department of Electrical Engineering and Computer Science; and Luis Videgaray, senior lecturer at MIT Sloan School of Management and director of MIT AI Policy for the World Project. Here, they discuss talk some of the key issues facing the AI policy landscape today and the challenges surrounding the deployment of AI. The three are co-organizers of the upcoming AI Policy Forum Summit on Sept. 28, which will further explore the issues discussed here.

    Q: Can you talk about the ­ongoing work of the AI Policy Forum and the AI policy landscape generally?

    Ozdaglar: There is no shortage of discussion about AI at different venues, but conversations are often high-level, focused on questions of ethics and principles, or on policy problems alone. The approach the AIPF takes to its work is to target specific questions with actionable policy solutions and engage with the stakeholders working directly in these areas. We work “behind the scenes” with smaller focus groups to tackle these challenges and aim to bring visibility to some potential solutions alongside the players working directly on them through larger gatherings.

    Q: AI impacts many sectors, which makes us naturally worry about its trustworthiness. Are there any emerging best practices for development and deployment of trustworthy AI?

    Madry: The most important thing to understand regarding deploying trustworthy AI is that AI technology isn’t some natural, preordained phenomenon. It is something built by people. People who are making certain design decisions.

    We thus need to advance research that can guide these decisions as well as provide more desirable solutions. But we also need to be deliberate and think carefully about the incentives that drive these decisions. 

    Now, these incentives stem largely from the business considerations, but not exclusively so. That is, we should also recognize that proper laws and regulations, as well as establishing thoughtful industry standards have a big role to play here too.

    Indeed, governments can put in place rules that prioritize the value of deploying AI while being keenly aware of the corresponding downsides, pitfalls, and impossibilities. The design of such rules will be an ongoing and evolving process as the technology continues to improve and change, and we need to adapt to socio-political realities as well.

    Q: Perhaps one of the most rapidly evolving domains in AI deployment is in the financial sector. From a policy perspective, how should governments, regulators, and lawmakers make AI work best for consumers in finance?

    Videgaray: The financial sector is seeing a number of trends that present policy challenges at the intersection of AI systems. For one, there is the issue of explainability. By law (in the U.S. and in many other countries), lenders need to provide explanations to customers when they take actions deleterious in whatever way, like denial of a loan, to a customer’s interest. However, as financial services increasingly rely on automated systems and machine learning models, the capacity of banks to unpack the “black box” of machine learning to provide that level of mandated explanation becomes tenuous. So how should the finance industry and its regulators adapt to this advance in technology? Perhaps we need new standards and expectations, as well as tools to meet these legal requirements.

    Meanwhile, economies of scale and data network effects are leading to a proliferation of AI outsourcing, and more broadly, AI-as-a-service is becoming increasingly common in the finance industry. In particular, we are seeing fintech companies provide the tools for underwriting to other financial institutions — be it large banks or small, local credit unions. What does this segmentation of the supply chain mean for the industry? Who is accountable for the potential problems in AI systems deployed through several layers of outsourcing? How can regulators adapt to guarantee their mandates of financial stability, fairness, and other societal standards?

    Q: Social media is one of the most controversial sectors of the economy, resulting in many societal shifts and disruptions around the world. What policies or reforms might be needed to best ensure social media is a force for public good and not public harm?

    Ozdaglar: The role of social media in society is of growing concern to many, but the nature of these concerns can vary quite a bit — with some seeing social media as not doing enough to prevent, for example, misinformation and extremism, and others seeing it as unduly silencing certain viewpoints. This lack of unified view on what the problem is impacts the capacity to enact any change. All of that is additionally coupled with the complexities of the legal framework in the U.S. spanning the First Amendment, Section 230 of the Communications Decency Act, and trade laws.

    However, these difficulties in regulating social media do not mean that there is nothing to be done. Indeed, regulators have begun to tighten their control over social media companies, both in the United States and abroad, be it through antitrust procedures or other means. In particular, Ofcom in the U.K. and the European Union is already introducing new layers of oversight to platforms. Additionally, some have proposed taxes on online advertising to address the negative externalities caused by current social media business model. So, the policy tools are there, if the political will and proper guidance exists to implement them. More

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    In-home wireless device tracks disease progression in Parkinson’s patients

    Parkinson’s disease is the fastest-growing neurological disease, now affecting more than 10 million people worldwide, yet clinicians still face huge challenges in tracking its severity and progression.

    Clinicians typically evaluate patients by testing their motor skills and cognitive functions during clinic visits. These semisubjective measurements are often skewed by outside factors — perhaps a patient is tired after a long drive to the hospital. More than 40 percent of individuals with Parkinson’s are never treated by a neurologist or Parkinson’s specialist, often because they live too far from an urban center or have difficulty traveling.

    In an effort to address these problems, researchers from MIT and elsewhere demonstrated an in-home device that can monitor a patient’s movement and gait speed, which can be used to evaluate Parkinson’s severity, the progression of the disease, and the patient’s response to medication.

    The device, which is about the size of a Wi-Fi router, gathers data passively using radio signals that reflect off the patient’s body as they move around their home. The patient does not need to wear a gadget or change their behavior. (A recent study, for example, showed that this type of device could be used to detect Parkinson’s from a person’s breathing patterns while sleeping.)

    The researchers used these devices to conduct a one-year at-home study with 50 participants. They showed that, by using machine-learning algorithms to analyze the troves of data they passively gathered (more than 200,000 gait speed measurements), a clinician could track Parkinson’s progression and medication response more effectively than they would with periodic, in-clinic evaluations.

    “By being able to have a device in the home that can monitor a patient and tell the doctor remotely about the progression of the disease, and the patient’s medication response so they can attend to the patient even if the patient can’t come to the clinic — now they have real, reliable information — that actually goes a long way toward improving equity and access,” says senior author Dina Katabi, the Thuan and Nicole Pham Professor in the Department of Electrical Engineering and Computer Science (EECS), and a principle investigator in the Computer Science and Artificial Intelligence Laboratory (CSAIL) and the MIT Jameel Clinic.

    The co-lead authors are EECS graduate students Yingcheng Liu and Guo Zhang. The research is published today in Science Translational Medicine.

    A human radar

    This work utilizes a wireless device previously developed in the Katabi lab that analyzes radio signals that bounce off people’s bodies. It transmits signals that use a tiny fraction of the power of a Wi-Fi router — these super-low-power signals don’t interfere with other wireless devices in the home. While radio signals pass through walls and other solid objects, they are reflected off humans due to the water in our bodies.  

    This creates a “human radar” that can track the movement of a person in a room. Radio waves always travel at the same speed, so the length of time it takes the signals to reflect back to the device indicates how the person is moving.

    The device incorporates a machine-learning classifier that can pick out the precise radio signals reflected off the patient even when there are other people moving around the room. Advanced algorithms use these movement data to compute gait speed — how fast the person is walking.

    Because the device operates in the background and runs all day, every day, it can collect a massive amount of data. The researchers wanted to see if they could apply machine learning to these datasets to gain insights about the disease over time.

    They gathered 50 participants, 34 of whom had Parkinson’s, and conducted a one-year study of in-home gait measurements Through the study, the researchers collected more than 200,000 individual measurements that they averaged to smooth out variability due to the conditions irrelevant to the disease. (For example, a patient may hurry up to answer an alarm or walk slower when talking on the phone.)

    They used statistical methods to analyze the data and found that in-home gait speed can be used to effectively track Parkinson’s progression and severity. For instance, they showed that gait speed declined almost twice as fast for individuals with Parkinson’s, compared to those without. 

    “Monitoring the patient continuously as they move around the room enabled us to get really good measurements of their gait speed. And with so much data, we were able to perform aggregation that allowed us to see very small differences,” Zhang says.

    Better, faster results

    Drilling down on these variabilities offered some key insights. For instance, the researchers showed that daily fluctuations in a patient’s walking speed correspond with how they are responding to their medication — walking speed may improve after a dose and then begin to decline after a few hours, as the medication impact wears off.

    “This enables us to objectively measure how your mobility responds to your medication. Previously, this was very cumbersome to do because this medication effect could only be measured by having the patient keep a journal,” Liu says.

    A clinician could use these data to adjust medication dosage more effectively and accurately. This is especially important since drugs used to treat disease symptoms can cause serious side effects if the patient receives too much.

    The researchers were able to demonstrate statistically significant results regarding Parkinson’s progression after studying 50 people for just one year. By contrast, an often-cited study by the Michael J. Fox Foundation involved more than 500 individuals and monitored them for more than five years, Katabi says.

    “For a pharmaceutical company or a biotech company trying to develop medicines for this disease, this could greatly reduce the burden and cost and speed up the development of new therapies,” she adds.

    Katabi credits much of the study’s success to the dedicated team of scientists and clinicians who worked together to tackle the many difficulties that arose along the way. For one, they began the study before the Covid-19 pandemic, so team members initially visited people’s homes to set up the devices. When that was no longer possible, they developed a user-friendly phone app to remotely help participants as they deployed the device at home.

    Through the course of the study, they learned to automate processes and reduce effort, especially for the participants and clinical team.

    This knowledge will prove useful as they look to deploy devices in at-home studies of other neurological disorders, such as Alzheimer’s, ALS, and Huntington’s. They also want to explore how these methods could be used, in conjunction with other work from the Katabi lab showing that Parkinson’s can be diagnosed by monitoring breathing, to collect a holistic set of markers that could diagnose the disease early and then be used to track and treat it.

    “This radio-wave sensor can enable more care (and research) to migrate from hospitals to the home where it is most desired and needed,” says Ray Dorsey, a professor of neurology at the University of Rochester Medical Center, co-author of Ending Parkinson’s, and a co-author of this research paper. “Its potential is just beginning to be seen. We are moving toward a day where we can diagnose and predict disease at home. In the future, we may even be able to predict and ideally prevent events like falls and heart attacks.”

    This work is supported, in part, by the National Institutes of Health and the Michael J. Fox Foundation. More

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    Empowering Cambridge youth through data activism

    For over 40 years, the Mayor’s Summer Youth Employment Program (MSYEP, or the Mayor’s Program) in Cambridge, Massachusetts, has been providing teenagers with their first work experience, but 2022 brought a new offering. Collaborating with MIT’s Personal Robots research group (PRG) and Responsible AI for Social Empowerment and Education (RAISE) this summer, MSYEP created a STEAM-focused learning site at the Institute. Eleven students joined the program to learn coding and programming skills through the lens of “Data Activism.”

    MSYEP’s partnership with MIT provides an opportunity for Cambridge high schoolers to gain exposure to more pathways for their future careers and education. The Mayor’s Program aims to respect students’ time and show the value of their work, so participants are compensated with an hourly wage as they learn workforce skills at MSYEP worksites. In conjunction with two ongoing research studies at MIT, PRG and RAISE developed the six-week Data Activism curriculum to equip students with critical-thinking skills so they feel prepared to utilize data science to challenge social injustice and empower their community.

    Rohan Kundargi, K-12 Community Outreach Administrator for MIT Office of Government and Community Relations (OGCR), says, “I see this as a model for a new type of partnership between MIT and Cambridge MSYEP. Specifically, an MIT research project that involves students from Cambridge getting paid to learn, research, and develop their own skills!”

    Cross-Cambridge collaboration

    Cambridge’s Office of Workforce Development initially contacted MIT OGCR about hosting a potential MSYEP worksite that taught Cambridge teens how to code. When Kundargi reached out to MIT pK-12 collaborators, MIT PRG’s graduate research assistant Raechel Walker proposed the Data Activism curriculum. Walker defines “data activism” as utilizing data, computing, and art to analyze how power operates in the world, challenge power, and empathize with people who are oppressed.

    Walker says, “I wanted students to feel empowered to incorporate their own expertise, talents, and interests into every activity. In order for students to fully embrace their academic abilities, they must remain comfortable with bringing their full selves into data activism.”

    As Kundargi and Walker recruited students for the Data Activism learning site, they wanted to make sure the cohort of students — the majority of whom are individuals of color — felt represented at MIT and felt they had the agency for their voice to be heard. “The pioneers in this field are people who look like them,” Walker says, speaking of well-known data activists Timnit Gebru, Rediet Abebe, and Joy Buolamwini.

    When the program began this summer, some of the students were not aware of the ways data science and artificial intelligence exacerbate systemic oppression in society, or some of the tools currently being used to mitigate those societal harms. As a result, Walker says, the students wanted to learn more about discriminatory design in every aspect of life. They were also interested in creating responsible machine learning algorithms and AI fairness metrics.

    A different side of STEAM

    The development and execution of the Data Activism curriculum contributed to Walker’s and postdoc Xiaoxue Du’s respective research at PRG. Walker is studying AI education, specifically creating and teaching data activism curricula for minoritized communities. Du’s research explores processes, assessments, and curriculum design that prepares educators to use, adapt, and integrate AI literacy curricula. Additionally, her research targets how to leverage more opportunities for students with diverse learning needs.

    The Data Activism curriculum utilizes a “libertatory computing” framework, a term Walker coined in her position paper with Professor Cynthia Breazeal, director of MIT RAISE, dean for digital learning, and head of PRG, and Eman Sherif, a then-undergraduate researcher from University of California at San Diego, titled “Liberty Computing for African American Students.” This framework ensures that students, especially minoritized students, acquire a sound racial identity, critical consciousness, collective obligation, liberation centered academic/achievement identity, as well as the activism skills to use computing to transform a multi-layered system of barriers in which racism persists. Walker says, “We encouraged students to demonstrate competency in every pillar because all of the pillars are interconnected and build upon each other.”

    Walker developed a series of interactive coding and project-based activities that focused on understanding systemic racism, utilizing data science to analyze systemic oppression, data drawing, responsible machine learning, how racism can be embedded into AI, and different AI fairness metrics.

    This was the students’ first time learning how to create data visualizations using the programming language Python and the data analysis tool Pandas. In one project meant to examine how different systems of oppression can affect different aspects of students’ own identities, students created datasets with data from their respective intersectional identities. Another activity highlighted African American achievements, where students analyzed two datasets about African American scientists, activists, artists, scholars, and athletes. Using the data visualizations, students then created zines about the African Americans who inspired them.

    RAISE hired Olivia Dias, Sophia Brady, Lina Henriquez, and Zeynep Yalcin through the MIT Undergraduate Research Opportunity Program (UROP) and PRG hired freelancer Matt Taylor to work with Walker on developing the curriculum and designing interdisciplinary experience projects. Walker and the four undergraduate researchers constructed an intersectional data analysis activity about different examples of systemic oppression. PRG also hired three high school students to test activities and offer insights about making the curriculum engaging for program participants. Throughout the program, the Data Activism team taught students in small groups, continually asked students how to improve each activity, and structured each lesson based on the students’ interests. Walker says Dias, Brady, Henriquez, and Yalcin were invaluable to cultivating a supportive classroom environment and helping students complete their projects.

    Cambridge Rindge and Latin School senior Nina works on her rubber block stamp that depicts the importance of representation in media and greater representation in the tech industry.

    Photo: Katherine Ouellette

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    Student Nina says, “It’s opened my eyes to a different side of STEM. I didn’t know what ‘data’ meant before this program, or how intersectionality can affect AI and data.” Before MSYEP, Nina took Intro to Computer Science and AP Computer Science, but she has been coding since Girls Who Code first sparked her interest in middle school. “The community was really nice. I could talk with other girls. I saw there needs to be more women in STEM, especially in coding.” Now she’s interested in applying to colleges with strong computer science programs so she can pursue a coding-related career.

    From MSYEP to the mayor’s office

    Mayor Sumbul Siddiqui visited the Data Activism learning site on Aug. 9, accompanied by Breazeal. A graduate of MSYEP herself, Siddiqui says, “Through hands-on learning through computer programming, Cambridge high school students have the unique opportunity to see themselves as data scientists. Students were able learn ways to combat discrimination that occurs through artificial intelligence.” In an Instagram post, Siddiqui also said, “I had a blast visiting the students and learning about their projects.”

    Students worked on an activity that asked them to envision how data science might be used to support marginalized communities. They transformed their answers into block-printed T-shirt designs, carving pictures of their hopes into rubber block stamps. Some students focused on the importance of data privacy, like Jacob T., who drew a birdcage to represent data stored and locked away by third party apps. He says, “I want to open that cage and restore my data to myself and see what can be done with it.”

    The subject of Cambridge Community Charter School student Jacob T.’s project was the importance of data privacy. For his T-shirt design, he drew a birdcage to represent data stored and locked away by third party apps. (From right to left:) Breazeal, Jacob T. Kiki, Raechel Walker, and Zeynep Yalcin.

    Photo: Katherine Ouellette

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    Many students wanted to see more representation in both the media they consume and across various professional fields. Nina talked about the importance of representation in media and how that could contribute to greater representation in the tech industry, while Kiki talked about encouraging more women to pursue STEM fields. Jesmin said, “I wanted to show that data science is accessible to everyone, no matter their origin or language you speak. I wrote ‘hello’ in Bangla, Arabic, and English, because I speak all three languages and they all resonate with me.”

    Student Jesmin (left) explains the concept of her T-shirt design to Mayor Siddiqui. She wants data science to be accessible to everyone, no matter their origin or language, so she drew a globe and wrote ‘hello’ in the three languages she speaks: Bangla, Arabic, and English.

    Photo: Katherine Ouellette

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    “Overall, I hope the students continue to use their data activism skills to re-envision a society that supports marginalized groups,” says Walker. “Moreover, I hope they are empowered to become data scientists and understand how their race can be a positive part of their identity.” More

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    Visualizing migration stories

    On July 27, 2020, 51 people migrating to the United States were found dead in an overheated trailer near the Mexican border. Understanding why migrants willingly take such risks is the topic of a recent exhibition and report, co-authored by researchers at MIT’s Civic Data Design Lab (CDDL). The research has been used by the U.S. Senate and the United Nations to develop new policies to address the challenges, dangers, and opportunities presented by migration in the Americas.

    To illustrate these motivations and risks, researchers at CDDL have designed an exhibition featuring digital and physical visualizations that encourage visitors to engage with migrants’ experiences more fully. “Distance Unknown” made its debut at the United Nations World Food Program (WFP) executive board meeting in Rome earlier this summer, with plans for additional exhibition stops over the next year.

    The exhibition is inspired by the 2021 report about migration, co-authored by CDDL, that highlighted economic distress as the main factor pushing migrants from Central America to the United States. The report’s findings were cited in a January 2022 letter from 35 U.S. senators to Homeland Security Secretary Alejandro Mayorkas and Secretary of State Antony Blinken (who leads the Biden administration’s migration task force) that advocated for addressing humanitarian needs in Central America. In June, the United States joined 20 countries in issuing the Los Angeles Declaration on Migration and Protection, which proposed expanded legal avenues to migration.

    “This exhibition takes a unique approach to visualizing migration stories by humanizing the data. Visitors to the exhibition can see the data in aggregate, but then they can dive deeper and learn migrants’ individual motivations,” says Sarah Williams, associate professor of technology and urban planning, director of the Civic Data Design Lab and the Norman B. Leventhal Center for Advanced Urbanism, and the lead designer of the exhibition.

    The data for the exhibition were taken from a survey of over 5,000 people in El Salvador, Guatemala, and Honduras conducted by the WFP and analyzed in the subsequent report. The report showed that approximately 43 percent of people surveyed in 2021 were considering migrating in the prior year, compared to 8 percent in 2019 — a change that comes after nearly two years of impacts from a global pandemic and as food insecurity dramatically increased in that region. Survey respondents cited low wages, unemployment, and minimal income levels as factors increasing their desire to migrate — ahead of reasons such as violence or natural disasters. 

    On the wall of the exhibition is a vibrant tapestry made of paper currency woven by 13 Latin American immigrants. Approximately 15-by-8 feet, this physical data visualization explains the root causes of migration from Central America documented by CDDL research. Each bill in the tapestry represents one migrant; visitors are invited to take a piece of the tapestry and scan it at a touch-screen station, where the story of that migrant appears. This allows visitors to dive deeper into the causes of migration by learning more about why an individual migrant family in the study left home, their household circumstances, and their personal stories.

    Another feature of the exhibition is an interactive map that allows visitors to explore the journeys and barriers that migrants face along the way. Created from a unique dataset collected by researchers from internet hotspots along the migration trail, the data showed that migrants from 43 countries (some as distant as China and Afghanistan) used this Latin American trail. The map highlights the Darien Gap region of Central America, one of the most dangerous and costly migration routes. The area is remote, without roads, and consists of swamps and dense jungle.

    The “Distance Unknown” exhibition represented data taken from internet hotspots on the migration pathway from the Darien Gap in Colombia to the Mexican border. This image shows migrant routes from 43 countries.

    Image courtesy of the Civic Data Design Lab.

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    The intense multimedia exhibition demonstrates the approach that Williams takes with her research. “One of the exciting features of the exhibition is that it shows that artistic forms of data visualization start new conversations, which create the dialogue necessary for policy change. We couldn’t be more thrilled with the way the exhibition helped influence the hearts and minds of people who have the political will to impact policy,” says Williams.

    In his opening remarks to the exhibition, David Beasley, executive director of WFP, explained that “when people have to migrate because they have no choice, it creates political problems on all sides,” and emphasized the importance of proposing solutions. Citing the 2021 report, Beasley noted that migrants from El Salvador, Guatemala, and Honduras collectively spent $2.2 billion to migrate to the United States in 2021, which is comparable to what their respective governments spend on primary education.

    The WFP hopes to bring the exhibition to other locations, including Washington, Geneva, New York, Madrid, Buenos Aires, and Panama. More

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    AI that can learn the patterns of human language

    Human languages are notoriously complex, and linguists have long thought it would be impossible to teach a machine how to analyze speech sounds and word structures in the way human investigators do.

    But researchers at MIT, Cornell University, and McGill University have taken a step in this direction. They have demonstrated an artificial intelligence system that can learn the rules and patterns of human languages on its own.

    When given words and examples of how those words change to express different grammatical functions (like tense, case, or gender) in one language, this machine-learning model comes up with rules that explain why the forms of those words change. For instance, it might learn that the letter “a” must be added to end of a word to make the masculine form feminine in Serbo-Croatian.

    This model can also automatically learn higher-level language patterns that can apply to many languages, enabling it to achieve better results.

    The researchers trained and tested the model using problems from linguistics textbooks that featured 58 different languages. Each problem had a set of words and corresponding word-form changes. The model was able to come up with a correct set of rules to describe those word-form changes for 60 percent of the problems.

    This system could be used to study language hypotheses and investigate subtle similarities in the way diverse languages transform words. It is especially unique because the system discovers models that can be readily understood by humans, and it acquires these models from small amounts of data, such as a few dozen words. And instead of using one massive dataset for a single task, the system utilizes many small datasets, which is closer to how scientists propose hypotheses — they look at multiple related datasets and come up with models to explain phenomena across those datasets.

    “One of the motivations of this work was our desire to study systems that learn models of datasets that is represented in a way that humans can understand. Instead of learning weights, can the model learn expressions or rules? And we wanted to see if we could build this system so it would learn on a whole battery of interrelated datasets, to make the system learn a little bit about how to better model each one,” says Kevin Ellis ’14, PhD ’20, an assistant professor of computer science at Cornell University and lead author of the paper.

    Joining Ellis on the paper are MIT faculty members Adam Albright, a professor of linguistics; Armando Solar-Lezama, a professor and associate director of the Computer Science and Artificial Intelligence Laboratory (CSAIL); and Joshua B. Tenenbaum, the Paul E. Newton Career Development Professor of Cognitive Science and Computation in the Department of Brain and Cognitive Sciences and a member of CSAIL; as well as senior author

    Timothy J. O’Donnell, assistant professor in the Department of Linguistics at McGill University, and Canada CIFAR AI Chair at the Mila – Quebec Artificial Intelligence Institute.

    The research is published today in Nature Communications.

    Looking at language 

    In their quest to develop an AI system that could automatically learn a model from multiple related datasets, the researchers chose to explore the interaction of phonology (the study of sound patterns) and morphology (the study of word structure).

    Data from linguistics textbooks offered an ideal testbed because many languages share core features, and textbook problems showcase specific linguistic phenomena. Textbook problems can also be solved by college students in a fairly straightforward way, but those students typically have prior knowledge about phonology from past lessons they use to reason about new problems.

    Ellis, who earned his PhD at MIT and was jointly advised by Tenenbaum and Solar-Lezama, first learned about morphology and phonology in an MIT class co-taught by O’Donnell, who was a postdoc at the time, and Albright.

    “Linguists have thought that in order to really understand the rules of a human language, to empathize with what it is that makes the system tick, you have to be human. We wanted to see if we can emulate the kinds of knowledge and reasoning that humans (linguists) bring to the task,” says Albright.

    To build a model that could learn a set of rules for assembling words, which is called a grammar, the researchers used a machine-learning technique known as Bayesian Program Learning. With this technique, the model solves a problem by writing a computer program.

    In this case, the program is the grammar the model thinks is the most likely explanation of the words and meanings in a linguistics problem. They built the model using Sketch, a popular program synthesizer which was developed at MIT by Solar-Lezama.

    But Sketch can take a lot of time to reason about the most likely program. To get around this, the researchers had the model work one piece at a time, writing a small program to explain some data, then writing a larger program that modifies that small program to cover more data, and so on.

    They also designed the model so it learns what “good” programs tend to look like. For instance, it might learn some general rules on simple Russian problems that it would apply to a more complex problem in Polish because the languages are similar. This makes it easier for the model to solve the Polish problem.

    Tackling textbook problems

    When they tested the model using 70 textbook problems, it was able to find a grammar that matched the entire set of words in the problem in 60 percent of cases, and correctly matched most of the word-form changes in 79 percent of problems.

    The researchers also tried pre-programming the model with some knowledge it “should” have learned if it was taking a linguistics course, and showed that it could solve all problems better.

    “One challenge of this work was figuring out whether what the model was doing was reasonable. This isn’t a situation where there is one number that is the single right answer. There is a range of possible solutions which you might accept as right, close to right, etc.,” Albright says.

    The model often came up with unexpected solutions. In one instance, it discovered the expected answer to a Polish language problem, but also another correct answer that exploited a mistake in the textbook. This shows that the model could “debug” linguistics analyses, Ellis says.

    The researchers also conducted tests that showed the model was able to learn some general templates of phonological rules that could be applied across all problems.

    “One of the things that was most surprising is that we could learn across languages, but it didn’t seem to make a huge difference,” says Ellis. “That suggests two things. Maybe we need better methods for learning across problems. And maybe, if we can’t come up with those methods, this work can help us probe different ideas we have about what knowledge to share across problems.”

    In the future, the researchers want to use their model to find unexpected solutions to problems in other domains. They could also apply the technique to more situations where higher-level knowledge can be applied across interrelated datasets. For instance, perhaps they could develop a system to infer differential equations from datasets on the motion of different objects, says Ellis.

    “This work shows that we have some methods which can, to some extent, learn inductive biases. But I don’t think we’ve quite figured out, even for these textbook problems, the inductive bias that lets a linguist accept the plausible grammars and reject the ridiculous ones,” he adds.

    “This work opens up many exciting venues for future research. I am particularly intrigued by the possibility that the approach explored by Ellis and colleagues (Bayesian Program Learning, BPL) might speak to how infants acquire language,” says T. Florian Jaeger, a professor of brain and cognitive sciences and computer science at the University of Rochester, who was not an author of this paper. “Future work might ask, for example, under what additional induction biases (assumptions about universal grammar) the BPL approach can successfully achieve human-like learning behavior on the type of data infants observe during language acquisition. I think it would be fascinating to see whether inductive biases that are even more abstract than those considered by Ellis and his team — such as biases originating in the limits of human information processing (e.g., memory constraints on dependency length or capacity limits in the amount of information that can be processed per time) — would be sufficient to induce some of the patterns observed in human languages.”

    This work was funded, in part, by the Air Force Office of Scientific Research, the Center for Brains, Minds, and Machines, the MIT-IBM Watson AI Lab, the Natural Science and Engineering Research Council of Canada, the Fonds de Recherche du Québec – Société et Culture, the Canada CIFAR AI Chairs Program, the National Science Foundation (NSF), and an NSF graduate fellowship. More