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    Dealing with the limitations of our noisy world

    Tamara Broderick first set foot on MIT’s campus when she was a high school student, as a participant in the inaugural Women’s Technology Program. The monthlong summer academic experience gives young women a hands-on introduction to engineering and computer science.

    What is the probability that she would return to MIT years later, this time as a faculty member?

    That’s a question Broderick could probably answer quantitatively using Bayesian inference, a statistical approach to probability that tries to quantify uncertainty by continuously updating one’s assumptions as new data are obtained.

    In her lab at MIT, the newly tenured associate professor in the Department of Electrical Engineering and Computer Science (EECS) uses Bayesian inference to quantify uncertainty and measure the robustness of data analysis techniques.

    “I’ve always been really interested in understanding not just ‘What do we know from data analysis,’ but ‘How well do we know it?’” says Broderick, who is also a member of the Laboratory for Information and Decision Systems and the Institute for Data, Systems, and Society. “The reality is that we live in a noisy world, and we can’t always get exactly the data that we want. How do we learn from data but at the same time recognize that there are limitations and deal appropriately with them?”

    Broadly, her focus is on helping people understand the confines of the statistical tools available to them and, sometimes, working with them to craft better tools for a particular situation.

    For instance, her group recently collaborated with oceanographers to develop a machine-learning model that can make more accurate predictions about ocean currents. In another project, she and others worked with degenerative disease specialists on a tool that helps severely motor-impaired individuals utilize a computer’s graphical user interface by manipulating a single switch.

    A common thread woven through her work is an emphasis on collaboration.

    “Working in data analysis, you get to hang out in everybody’s backyard, so to speak. You really can’t get bored because you can always be learning about some other field and thinking about how we can apply machine learning there,” she says.

    Hanging out in many academic “backyards” is especially appealing to Broderick, who struggled even from a young age to narrow down her interests.

    A math mindset

    Growing up in a suburb of Cleveland, Ohio, Broderick had an interest in math for as long as she can remember. She recalls being fascinated by the idea of what would happen if you kept adding a number to itself, starting with 1+1=2 and then 2+2=4.

    “I was maybe 5 years old, so I didn’t know what ‘powers of two’ were or anything like that. I was just really into math,” she says.

    Her father recognized her interest in the subject and enrolled her in a Johns Hopkins program called the Center for Talented Youth, which gave Broderick the opportunity to take three-week summer classes on a range of subjects, from astronomy to number theory to computer science.

    Later, in high school, she conducted astrophysics research with a postdoc at Case Western University. In the summer of 2002, she spent four weeks at MIT as a member of the first class of the Women’s Technology Program.

    She especially enjoyed the freedom offered by the program, and its focus on using intuition and ingenuity to achieve high-level goals. For instance, the cohort was tasked with building a device with LEGOs that they could use to biopsy a grape suspended in Jell-O.

    The program showed her how much creativity is involved in engineering and computer science, and piqued her interest in pursuing an academic career.

    “But when I got into college at Princeton, I could not decide — math, physics, computer science — they all seemed super-cool. I wanted to do all of it,” she says.

    She settled on pursuing an undergraduate math degree but took all the physics and computer science courses she could cram into her schedule.

    Digging into data analysis

    After receiving a Marshall Scholarship, Broderick spent two years at Cambridge University in the United Kingdom, earning a master of advanced study in mathematics and a master of philosophy in physics.

    In the UK, she took a number of statistics and data analysis classes, including her first class on Bayesian data analysis in the field of machine learning.

    It was a transformative experience, she recalls.

    “During my time in the U.K., I realized that I really like solving real-world problems that matter to people, and Bayesian inference was being used in some of the most important problems out there,” she says.

    Back in the U.S., Broderick headed to the University of California at Berkeley, where she joined the lab of Professor Michael I. Jordan as a grad student. She earned a PhD in statistics with a focus on Bayesian data analysis. 

    She decided to pursue a career in academia and was drawn to MIT by the collaborative nature of the EECS department and by how passionate and friendly her would-be colleagues were.

    Her first impressions panned out, and Broderick says she has found a community at MIT that helps her be creative and explore hard, impactful problems with wide-ranging applications.

    “I’ve been lucky to work with a really amazing set of students and postdocs in my lab — brilliant and hard-working people whose hearts are in the right place,” she says.

    One of her team’s recent projects involves a collaboration with an economist who studies the use of microcredit, or the lending of small amounts of money at very low interest rates, in impoverished areas.

    The goal of microcredit programs is to raise people out of poverty. Economists run randomized control trials of villages in a region that receive or don’t receive microcredit. They want to generalize the study results, predicting the expected outcome if one applies microcredit to other villages outside of their study.

    But Broderick and her collaborators have found that results of some microcredit studies can be very brittle. Removing one or a few data points from the dataset can completely change the results. One issue is that researchers often use empirical averages, where a few very high or low data points can skew the results.

    Using machine learning, she and her collaborators developed a method that can determine how many data points must be dropped to change the substantive conclusion of the study. With their tool, a scientist can see how brittle the results are.

    “Sometimes dropping a very small fraction of data can change the major results of a data analysis, and then we might worry how far those conclusions generalize to new scenarios. Are there ways we can flag that for people? That is what we are getting at with this work,” she explains.

    At the same time, she is continuing to collaborate with researchers in a range of fields, such as genetics, to understand the pros and cons of different machine-learning techniques and other data analysis tools.

    Happy trails

    Exploration is what drives Broderick as a researcher, and it also fuels one of her passions outside the lab. She and her husband enjoy collecting patches they earn by hiking all the trails in a park or trail system.

    “I think my hobby really combines my interests of being outdoors and spreadsheets,” she says. “With these hiking patches, you have to explore everything and then you see areas you wouldn’t normally see. It is adventurous, in that way.”

    They’ve discovered some amazing hikes they would never have known about, but also embarked on more than a few “total disaster hikes,” she says. But each hike, whether a hidden gem or an overgrown mess, offers its own rewards.

    And just like in her research, curiosity, open-mindedness, and a passion for problem-solving have never led her astray. More

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    Generating opportunities with generative AI

    Talking with retail executives back in 2010, Rama Ramakrishnan came to two realizations. First, although retail systems that offered customers personalized recommendations were getting a great deal of attention, these systems often provided little payoff for retailers. Second, for many of the firms, most customers shopped only once or twice a year, so companies didn’t really know much about them.

    “But by being very diligent about noting down the interactions a customer has with a retailer or an e-commerce site, we can create a very nice and detailed composite picture of what that person does and what they care about,” says Ramakrishnan, professor of the practice at the MIT Sloan School of Management. “Once you have that, then you can apply proven algorithms from machine learning.”

    These realizations led Ramakrishnan to found CQuotient, a startup whose software has now become the foundation for Salesforce’s widely adopted AI e-commerce platform. “On Black Friday alone, CQuotient technology probably sees and interacts with over a billion shoppers on a single day,” he says.

    After a highly successful entrepreneurial career, in 2019 Ramakrishnan returned to MIT Sloan, where he had earned master’s and PhD degrees in operations research in the 1990s. He teaches students “not just how these amazing technologies work, but also how do you take these technologies and actually put them to use pragmatically in the real world,” he says.

    Additionally, Ramakrishnan enjoys participating in MIT executive education. “This is a great opportunity for me to convey the things that I have learned, but also as importantly, to learn what’s on the minds of these senior executives, and to guide them and nudge them in the right direction,” he says.

    For example, executives are understandably concerned about the need for massive amounts of data to train machine learning systems. He can now guide them to a wealth of models that are pre-trained for specific tasks. “The ability to use these pre-trained AI models, and very quickly adapt them to your particular business problem, is an incredible advance,” says Ramakrishnan.

    Rama Ramakrishnan – Utilizing AI in Real World Applications for Intelligent WorkVideo: MIT Industrial Liaison Program

    Understanding AI categories

    “AI is the quest to imbue computers with the ability to do cognitive tasks that typically only humans can do,” he says. Understanding the history of this complex, supercharged landscape aids in exploiting the technologies.

    The traditional approach to AI, which basically solved problems by applying if/then rules learned from humans, proved useful for relatively few tasks. “One reason is that we can do lots of things effortlessly, but if asked to explain how we do them, we can’t actually articulate how we do them,” Ramakrishnan comments. Also, those systems may be baffled by new situations that don’t match up to the rules enshrined in the software.

    Machine learning takes a dramatically different approach, with the software fundamentally learning by example. “You give it lots of examples of inputs and outputs, questions and answers, tasks and responses, and get the computer to automatically learn how to go from the input to the output,” he says. Credit scoring, loan decision-making, disease prediction, and demand forecasting are among the many tasks conquered by machine learning.

    But machine learning only worked well when the input data was structured, for instance in a spreadsheet. “If the input data was unstructured, such as images, video, audio, ECGs, or X-rays, it wasn’t very good at going from that to a predicted output,” Ramakrishnan says. That means humans had to manually structure the unstructured data to train the system.

    Around 2010 deep learning began to overcome that limitation, delivering the ability to directly work with unstructured input data, he says. Based on a longstanding AI strategy known as neural networks, deep learning became practical due to the global flood tide of data, the availability of extraordinarily powerful parallel processing hardware called graphics processing units (originally invented for video games) and advances in algorithms and math.

    Finally, within deep learning, the generative AI software packages appearing last year can create unstructured outputs, such as human-sounding text, images of dogs, and three-dimensional models. Large language models (LLMs) such as OpenAI’s ChatGPT go from text inputs to text outputs, while text-to-image models such as OpenAI’s DALL-E can churn out realistic-appearing images.

    Rama Ramakrishnan – Making Note of Little Data to Improve Customer ServiceVideo: MIT Industrial Liaison Program

    What generative AI can (and can’t) do

    Trained on the unimaginably vast text resources of the internet, a LLM’s “fundamental capability is to predict the next most likely, most plausible word,” Ramakrishnan says. “Then it attaches the word to the original sentence, predicts the next word again, and keeps on doing it.”

    “To the surprise of many, including a lot of researchers, an LLM can do some very complicated things,” he says. “It can compose beautifully coherent poetry, write Seinfeld episodes, and solve some kinds of reasoning problems. It’s really quite remarkable how next-word prediction can lead to these amazing capabilities.”

    “But you have to always keep in mind that what it is doing is not so much finding the correct answer to your question as finding a plausible answer your question,” Ramakrishnan emphasizes. Its content may be factually inaccurate, irrelevant, toxic, biased, or offensive.

    That puts the burden on users to make sure that the output is correct, relevant, and useful for the task at hand. “You have to make sure there is some way for you to check its output for errors and fix them before it goes out,” he says.

    Intense research is underway to find techniques to address these shortcomings, adds Ramakrishnan, who expects many innovative tools to do so.

    Finding the right corporate roles for LLMs

    Given the astonishing progress in LLMs, how should industry think about applying the software to tasks such as generating content?

    First, Ramakrishnan advises, consider costs: “Is it a much less expensive effort to have a draft that you correct, versus you creating the whole thing?” Second, if the LLM makes a mistake that slips by, and the mistaken content is released to the outside world, can you live with the consequences?

    “If you have an application which satisfies both considerations, then it’s good to do a pilot project to see whether these technologies can actually help you with that particular task,” says Ramakrishnan. He stresses the need to treat the pilot as an experiment rather than as a normal IT project.

    Right now, software development is the most mature corporate LLM application. “ChatGPT and other LLMs are text-in, text-out, and a software program is just text-out,” he says. “Programmers can go from English text-in to Python text-out, as well as you can go from English-to-English or English-to-German. There are lots of tools which help you write code using these technologies.”

    Of course, programmers must make sure the result does the job properly. Fortunately, software development already offers infrastructure for testing and verifying code. “This is a beautiful sweet spot,” he says, “where it’s much cheaper to have the technology write code for you, because you can very quickly check and verify it.”

    Another major LLM use is content generation, such as writing marketing copy or e-commerce product descriptions. “Again, it may be much cheaper to fix ChatGPT’s draft than for you to write the whole thing,” Ramakrishnan says. “However, companies must be very careful to make sure there is a human in the loop.”

    LLMs also are spreading quickly as in-house tools to search enterprise documents. Unlike conventional search algorithms, an LLM chatbot can offer a conversational search experience, because it remembers each question you ask. “But again, it will occasionally make things up,” he says. “In terms of chatbots for external customers, these are very early days, because of the risk of saying something wrong to the customer.”

    Overall, Ramakrishnan notes, we’re living in a remarkable time to grapple with AI’s rapidly evolving potentials and pitfalls. “I help companies figure out how to take these very transformative technologies and put them to work, to make products and services much more intelligent, employees much more productive, and processes much more efficient,” he says. More

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    Improving accessibility of online graphics for blind users

    The beauty of a nice infographic published alongside a news or magazine story is that it makes numeric data more accessible to the average reader. But for blind and visually impaired users, such graphics often have the opposite effect.

    For visually impaired users — who frequently rely on screen-reading software that speaks words or numbers aloud as the user moves a cursor across the screen — a graphic may be nothing more than a few words of alt text, such as a chart’s title. For instance, a map of the United States displaying population rates by county might have alt text in the HTML that says simply, “A map of the United States with population rates by county.” The data has been buried in an image, making it entirely inaccessible.

    “Charts have these various visual features that, as a [sighted] reader, you can shift your attention around, look at high-level patterns, look at individual data points, and you can do this on the fly,” says Jonathan Zong, a 2022 MIT Morningside Academy for Design (MAD) Fellow and PhD student in computer science, who points out that even when a graphic includes alt text that interprets the data, the visually impaired user must accept the findings as presented.

    “If you’re [blind and] using a screen reader, the text description imposes a linear predefined reading order. So, you’re beholden to the decisions that the person who wrote the text made about what information was important to include.”

    While some graphics do include data tables that a screen reader can read, it requires the user to remember all the data from each row and column as they move on to the next one. According to the National Federation of the Blind, Zong says, there are 7 million people living in the United States with visual disabilities, and nearly 97 percent of top-level pages on the internet are not accessible to screen readers. The problem, he points out, is an especially difficult one for blind researchers to get around. Some researchers with visual impairments rely on a sighted collaborator to read and help interpret graphics in peer-reviewed research.

    Working with the Visualization Group at the Computer Science and Artificial Intelligence Lab (CSAIL) on a project led by Associate Professor Arvind Satyanarayan that includes Daniel Hajas, a blind researcher and innovation manager at the Global Disability Innovation Hub in England, Zong and others have written an open-source Javascript software program named Olli that solves this problem when it’s included on a website. Olli is able to go from big-picture analysis of a chart to the finest grain of detail to give the user the ability to select the degree of granularity that interests them.

    “We want to design richer screen-reader experiences for visualization with a hierarchical structure, multiple ways to navigate, and descriptions at varying levels of granularity to provide self-guided, open-ended exploration for the user.”

    Next steps with Olli are incorporating multi-sensory software to integrate text and visuals with sound, such as having a musical note that moves up or down the harmonic scale to indicate the direction of data on a linear graph, and possibly even developing tactile interpretations of data. Like most of the MAD Fellows, Zong integrates his science and engineering skills with design and art to create solutions to real-world problems affecting individuals. He’s been recognized for his work in both the visual arts and computer science. He holds undergraduate degrees in computer science and visual arts with a focus on graphic design from Princeton University, where his research was on the ethics of data collection.

    “The throughline is the idea that design can help us make progress on really tough social and ethical questions,” Zong says, calling software for accessible data visualization an “intellectually rich area for design.” “We’re thinking about ways to translate charts and graphs into text descriptions that can get read aloud as speech, or thinking about other kinds of audio mappings to sonify data, and we’re even exploring some tactile methods to understand data,” he says.

    “I get really excited about design when it’s a way to both create things that are useful to people in everyday life and also make progress on larger conversations about technology and society. I think working in accessibility is a great way to do that.”

    Another problem at the intersection of technology and society is the ethics of taking user data from social media for large-scale studies without the users’ awareness. While working as a summer graduate research fellow at Cornell’s Citizens and Technology Lab, Zong helped create an open-source software called Bartleby that can be used in large anonymous data research studies. After researchers collect data, but before analysis, Bartleby would automatically send an email message to every user whose data was included, alert them to that fact and offer them the choice to review the resulting data table and opt out of the study. Bartleby was honored in the student category of Fast Company’s Innovation by Design Awards for 2022. In November the same year, Forbes magazine named Jonathan Zong in its Forbes 30 Under 30 in Science 2023 list for his work in data visualization accessibility.

    The underlying theme to all Zong’s work is the exploration of autonomy and agency, even in his artwork, which is heavily inclusive of text and semiotic play. In “Public Display,” he created a handmade digital display font by erasing parts of celebrity faces that were taken from a facial recognition dataset. The piece was exhibited in 2020 in MIT’s Wiesner Gallery, and received the third-place prize in the MIT Schnitzer Prize in the Visual Arts that year. The work deals not only with the neurological aspects of distinguishing faces from typefaces, but also with the implications for erasing individuals’ identities through the practice of using facial recognition programs that often target individuals in communities of color in unfair ways. Another of his works, “Biometric Sans,” a typography system that stretches letters based on a person’s typing speed, will be included in a show at the Harvard Science Center sometime next fall.

    “MAD, particularly the large events MAD jointly hosted, played a really important function in showing the rest of MIT that this is the kind of work we value. This is what design can look like and is capable of doing. I think it all contributes to that culture shift where this kind of interdisciplinary work can be valued, recognized, and serve the public.

    “There are shared ideas around embodiment and representation that tie these different pursuits together for me,” Zong says. “In the ethics work, and the art on surveillance, I’m thinking about whether data collectors are representing people the way they want to be seen through data. And similarly, the accessibility work is about whether we can make systems that are flexible to the way people want to use them.” More

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    Advancing social studies at MIT Sloan

    Around 2010, Facebook was a relatively small company with about 2,000 employees. So, when a PhD student named Dean Eckles showed up to serve an intership at the firm, he landed in a position with some real duties.

    Eckles essentially became the primary data scientist for the product manager who was overseeing the platform’s news feeds. That manager would pepper Eckles with questions. How exactly do people influence each other online? If Facebook tweaked its content-ranking algorithms, what would happen? What occurs when you show people more photos?

    As a doctoral candidate already studying social influence, Eckles was well-equipped to think about such questions, and being at Facebook gave him a lot of data to study them. 

    “If you show people more photos, they post more photos themselves,” Eckles says. “In turn, that affects the experience of all their friends. Plus they’re getting more likes and more comments. It affects everybody’s experience. But can you account for all of these compounding effects across the network?”

    Eckles, now an associate professor in the MIT Sloan School of Management and an affiliate faculty member of the Institute for Data, Systems, and Society, has made a career out of thinking carefully about that last question. Studying social networks allows Eckles to tackle significant questions involving, for example, the economic and political effects of social networks, the spread of misinformation, vaccine uptake during the Covid-19 crisis, and other aspects of the formation and shape of social networks. For instance, one study he co-authored this summer shows that people who either move between U.S. states, change high schools, or attend college out of state, wind up with more robust social networks, which are strongly associated with greater economic success.

    Eckles maintains another research channel focused on what scholars call “causal inference,” the methods and techniques that allow researchers to identify cause-and-effect connections in the world.

    “Learning about cause-and-effect relationships is core to so much science,” Eckles says. “In behavioral, social, economic, or biomedical science, it’s going to be hard. When you start thinking about humans, causality gets difficult. People do things strategically, and they’re electing into situations based on their own goals, so that complicates a lot of cause-and-effect relationships.”

    Eckles has now published dozens of papers in each of his different areas of work; for his research and teaching, Eckles received tenure from MIT last year.

    Five degrees and a job

    Eckles grew up in California, mostly near the Lake Tahoe area. He attended Stanford University as an undergraduate, arriving on campus in fall 2002 — and didn’t really leave for about a decade. Eckles has five degrees from Stanford. As an undergrad, he received a BA in philosophy and a BS in symbolic systems, an interdisciplinary major combining computer science, philosophy, psychology, and more. Eckles was set to attend Oxford University for graduate work in philosophy but changed his mind and stayed at Stanford for an MS in symbolic systems too. 

    “[Oxford] might have been a great experience, but I decided to focus more on the tech side of things,” he says.

    After receiving his first master’s degree, Eckles did take a year off from school and worked for Nokia, although the firm’s offices were adjacent to the Stanford campus and Eckles would sometimes stop and talk to faculty during the workday. Soon he was enrolled at Stanford again, this time earning his PhD in communication, in 2012, while receiving an MA in statistics the year before. His doctoral dissertation wound up being about peer influence in networks. PhD in hand, Eckles promptly headed back to Facebook, this time for three years as a full-time researcher.

     “They were really supportive of the work I was doing,” Eckles says.

    Still, Eckles remained interested in moving into academia, and joined the MIT faculty in 2017 with a position in MIT Sloan’s Marketing Group. The group consists of a set of scholars with far-ranging interests, from cognitive science to advertising to social network dynamics.

    “Our group reflects something deeper about the Sloan school and about MIT as well, an openness to doing things differently and not having to fit into narrowly defined tracks,” Eckles says.

    For that matter, MIT has many faculty in different domains who work on causal inference, and whose work Eckles quickly cites — including economists Victor Chernozhukov and Alberto Abadie, and Joshua Angrist, whose book “Mostly Harmless Econometrics” Eckles name-checks as an influence.

    “I’ve been fortunate in my career that causal inference turned out to be a hot area,” Eckles says. “But I think it’s hot for good reasons. People started to realize that, yes, causal inference is really important. There are economists, computer scientists, statisticians, and epidemiologists who are going to the same conferences and citing each other’s papers. There’s a lot happening.”

    How do networks form?

    These days, Eckles is interested in expanding the questions he works on. In the past, he has often studied existing social networks and looked at their effects. For instance: One study Eckles co-authored, examining the 2012 U.S. elections, found that get-out-the-vote messages work very well, especially when relayed via friends.

    That kind of study takes the existence of the network as a given, though. Another kind of research question is, as Eckles puts it, “How do social networks form and evolve? And what are the consequences of these network structures?” His recent study about social networks expanding as people move around and change schools is one example of research that digs into the core life experiences underlying social networks.

    “I’m excited about doing more on how these networks arise and what factors, including everything from personality to public transit, affect their formation,” Eckles says.

    Understanding more about how social networks form gets at key questions about social life and civic structure. Suppose research shows how some people develop and maintain beneficial connections in life; it’s possible that those insights could be applied to programs helping people in more disadvantaged situations realize some of the same opportunities.

    “We want to act on things,” Eckles says. “Sometimes people say, ‘We care about prediction.’ I would say, ‘We care about prediction under intervention.’ We want to predict what’s going to happen if we try different things.”

    Ultimately, Eckles reflects, “Trying to reason about the origins and maintenance of social networks, and the effects of networks, is interesting substantively and methodologically. Networks are super-high-dimensional objects, even just a single person’s network and all its connections. You have to summarize it, so for instance we talk about weak ties or strong ties, but do we have the correct description? There are fascinating questions that require development, and I’m eager to keep working on them.”   More

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    Summer research offers a springboard to advanced studies

    Doctoral studies at MIT aren’t a calling for everyone, but they can be for anyone who has had opportunities to discover that science and technology research is their passion and to build the experience and skills to succeed. For Taylor Baum, Josefina Correa Menéndez, and Karla Alejandra Montejo, three graduate students in just one lab of The Picower Institute for Learning and Memory, a pivotal opportunity came via the MIT Summer Research Program in Biology and Neuroscience (MSRP-Bio). When a student finds MSRP-Bio, it helps them find their future in research. 

    In the program, undergraduate STEM majors from outside MIT spend the summer doing full-time research in the departments of Biology, Brain and Cognitive Sciences (BCS), or the Center for Brains, Minds and Machines (CBMM). They gain lab skills, mentoring, preparation for graduate school, and connections that might last a lifetime. Over the last two decades, a total of 215 students from underrepresented minority groups, who are from economically disadvantaged backgrounds, first-generation or nontraditional college students, or students with disabilities have participated in research in BCS or CBMM labs.  

    Like Baum, Correa Menéndez, and Montejo, the vast majority go on to pursue graduate studies, says Diversity and Outreach Coordinator Mandana Sassanfar, who runs the program. For instance, among 91 students who have worked in Picower Institute labs, 81 have completed their undergraduate studies. Of those, 46 enrolled in PhD programs at MIT or other schools such as Cornell, Yale, Stanford, and Princeton universities, and the University of California System. Another 12 have gone to medical school, another seven are in MD/PhD programs, and three have earned master’s degrees. The rest are studying as post-baccalaureates or went straight into the workforce after earning their bachelor’s degree. 

    After participating in the program, Baum, Correa Menéndez, and Montejo each became graduate students in the research group of Emery N. Brown, the Edward Hood Taplin Professor of Computational Neuroscience and Medical Engineering in The Picower Institute and the Institute for Medical Engineering and Science. The lab combines statistical, computational, and experimental neuroscience methods to study how general anesthesia affects the central nervous system to ultimately improve patient care and advance understanding of the brain. Brown says the students have each been doing “off-the-scale” work, in keeping with the excellence he’s seen from MSRP BIO students over the years. For example, on Aug. 10 Baum and Correa Menéndez were honored with MathWorks Fellowships.

    “I think MSRP is fantastic. Mandana does this amazing job of getting students who are quite talented to come to MIT to realize that they can move their game to the next level. They have the capacity to do it. They just need the opportunities,” Brown says. “These students live up to the expectations that you have of them. And now as graduate students, they’re taking on hard problems and they’re solving them.” 

    Paths to PhD studies 

    Pursuing a PhD is hardly a given. Many young students have never considered graduate school or specific fields of study like neuroscience or electrical engineering. But Sassanfar engages students across the country to introduce them to the opportunity MSRP-Bio provides to gain exposure, experience, and mentoring in advanced fields. Every fall, after the program’s students have returned to their undergraduate institutions, she visits schools in places as far flung as Florida, Maryland, Puerto Rico, and Texas and goes to conferences for diverse science communities such as ABRCMS and SACNAS to spread the word. 

    Taylor Baum

    Photo courtesy of Taylor Baum.

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    When Baum first connected with the program in 2017, she was finding her way at Penn State University. She had been majoring in biology and music composition but had just switched the latter to engineering following a conversation over coffee exposing her to brain-computer interfacing technology, in which detecting brain signals of people with full-body paralysis could improve their quality of life by enabling control of computers or wheelchairs. Baum became enthusiastic about the potential to build similar systems, but as a new engineering student, she struggled to find summer internships and research opportunities. 

    “I got rejected from every single progam except the MIT Center for Brains, Minds and Machines MSRP,” she recalls with a chuckle. 

    Baum thrived in MSRP-Bio, working in Brown’s lab for three successive summers. At each stage, she said, she gained more research skills, experience, and independence. When she graduated, she was sure she wanted to go to graduate school and applied to four of her dream schools. She accepted MIT’s offer to join the Department of Electrical Engineering and Computer Science, where she is co-advised by faculty members there and by Brown. She is now working to develop a system grounded in cardiovascular physiology that can improve blood pressure management. A tool for practicing anesthesiologists, the system automates the dosing of drugs to maintain a patient’s blood pressure at safe levels in the operating room or intensive care unit. 

    More than that, Baum not only is leading an organization advancing STEM education in Puerto Rico, but also is helping to mentor a current MSRP-Bio student in the Brown lab. 

    “MSRP definitely bonds everyone who has participated in it,” Baum says. “If I see anyone who I know participated in MSRP, we could have an immediate conversation. I know that most of us, if we needed help, we’d feel comfortable asking for help from someone from MSRP. With that shared experience, we have a sense of camaraderie, and community.” 

    In fact, a few years ago when a former MSRP-Bio student named Karla Montejo was applying to MIT, Baum provided essential advice and feedback about the application process, Montejo says. Now, as a graduate student, Montejo has become a mentor for the program in her own right, Sassanfar notes. For instance, Montejo serves on program alumni panels that advise new MSRP-Bio students. 

    Karla Alejandra Montejo

    Photo courtesy of Karla Alejandra Montejo.

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    Montejo’s family immigrated to Miami from Cuba when she was a child. The magnet high school she attended was so new that students were encouraged to help establish the school’s programs. She forged a path into research. 

    “I didn’t even know what research was,” she says. “I wanted to be a doctor, and I thought maybe it would help me on my resume. I thought it would be kind of like shadowing, but no, it was really different. So I got really captured by research when I was in high school.” 

    Despite continuing to pursue research in college at Florida International University, Montejo didn’t get into graduate school on her first attempt because she hadn’t yet learned how to focus her application. But Sassanfar had visited FIU to recruit students and through that relationship Montejo had already gone through MIT’s related Quantitative Methods Workshop (QMW). So Montejo enrolled in MSRP-Bio, working in the CBMM-affiliated lab of Gabriel Kreiman at Boston Children’s Hospital. 

    “I feel like Mandana really helped me out, gave me a break, and the MSRP experience pretty much solidified that I really wanted to come to MIT,” Montejo says. 

    In the QMW, Montejo learned she really liked computational neuroscience, and in Kreiman’s lab she got to try her hand at computational modeling of the cognition involved in making perceptual sense of complex scenes. Montejo realized she wanted to work on more biologically based neuroscience problems. When the summer ended, because she was off the normal graduate school cycle for now, she found a two-year post-baccalaurate program at Mayo Clinic studying the role a brain cell type called astrocytes might have in the Parkinson’s disease treatment deep brain stimulation. 

    When it came time to reapply to graduate schools (with the help of Baum and others in the BCS Application Assistance Program) Montejo applied to MIT and got in, joining the Brown lab. Now she’s working on modeling the role of  metabolic processes in the changing of brain rhythms under anesthesia, taking advantage of how general anesthesia predictably changes brain states. The effects anesthetic drugs have on cell metabolism and the way that ultimately affects levels of consciousness reveals important aspects of how metabolism affects brain circuits and systems. Earlier this month, for instance, Montejo co-led a paper the lab published in The Proceedings of the National Academy of Sciences detailing the neuroscience of a patient’s transition into an especially deep state of unconsciousness called “burst suppression.” 

    Josefina Correa Menendez

    Photo: David Orenstein

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    A signature of the Brown lab’s work is rigorous statistical analysis and methods, for instance to discern brain arousal states from EEG measures of brain rhythms. A PhD candidate in MIT’s Interdisciplinary Doctoral Program in Statistics, Correa Menéndez is advancing the use of Bayesian hierarchical models for neural data analysis. These statistical models offer a principled way of pooling information across datasets. One of her models can help scientists better understand the way neurons can “spike” with electrical activity when the brain is presented with a stimulus. The other’s power is in discerning critical features such as arousal states of the brain under general anesthesia from electrophysiological recordings. 

    Though she now works with complex equations and computations as a PhD candidate in neuroscience and statistics, Correa Menéndez was mostly interested in music art as a high school student at Academia María Reina in San Juan and then architecture in college at the University of Puerto Rico at Río Piedras. It was discussions at the intersection of epistemology and art during an art theory class that inspired Correa Menéndez to switch her major to biology and to take computer science classes, too. 

    When Sassanfar visited Puerto Rico in 2017, a computer science professor (Patricia Ordóñez) suggested that Correa Menéndez apply for a chance to attend the QMW. She did, and that led her to also participate in MSRP-Bio in the lab of Sherman Fairchild Professor Matt Wilson (a faculty member in BCS, CBMM, and the Picower Institute). She joined in the lab’s studies of how spatial memories are represented in the hippocampus and how the brain makes use of those memories to help understand the world around it. With mentoring from then-postdoc Carmen Varela (now a faculty member at Florida State University), the experience not only exposed her to neuroscience, but also helped her gain skills and experience with lab experiments, building research tools, and conducting statistical analyses. She ended up working in the Wilson lab as a research scholar for a year and began her graduate studies in September 2018.  

    Classes she took with Brown as a research scholar inspired her to join his lab as a graduate student. 

    “Taking the classes with Emery and also doing experiments made me aware of the role of statistics in the scientific process: from the interpretation of results to the analysis and the design of experiments,” she says. “More often than not, in science, statistics becomes this sort of afterthought — this ‘annoying’ thing that people need to do to get their paper published. But statistics as a field is actually a lot more than that. It’s a way of thinking about data. Particularly, Bayesian modeling provides a principled inference framework for combining prior knowledge into a hypothesis that you can test with data.” 

    To be sure, no one starts out with such inspiration about scientific scholarship, but MSRP-Bio helps students find that passion for research and the paths that opens up.   More

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    Embracing the future we need

    When you picture MIT doctoral students taking small PhD courses together, you probably don’t imagine them going on class field trips. But it does happen, sometimes, and one of those trips changed Andy Sun’s career.

    Today, Sun is a faculty member at the MIT Sloan School of Management and a leading global expert on integrating renewable energy into the electric grid. Back in 2007, Sun was an operations research PhD candidate with a diversified academic background: He had studied electrical engineering, quantum computing, and analog computing but was still searching for a doctoral research subject involving energy. 

    One day, as part of a graduate energy class taught by visiting professor Ignacio J. Pérez Arriaga, the students visited the headquarters of ISO-New England, the organization that operates New England’s entire power grid and wholesale electricity market. Suddenly, it hit Sun. His understanding of engineering, used to design and optimize computing systems, could be applied to the grid as a whole, with all its connections, circuitry, and need for efficiency. 

    “The power grids in the U.S. continent are composed of two major interconnections, the Western Interconnection, the Eastern Interconnection, and one minor interconnection, the Texas grid,” Sun says. “Within each interconnection, the power grid is one big machine, essentially. It’s connected by tens of thousands of miles of transmission lines, thousands of generators, and consumers, and if anything is not synchronized, the system may collapse. It’s one of the most complicated engineering systems.”

    And just like that, Sun had a subject he was motivated to pursue. “That’s how I got into this field,” he says. “Taking a field trip.”Sun has barely looked back. He has published dozens of papers about optimizing the flow of intermittent renewable energy through the electricity grid, a major practical issue for grid operators, while also thinking broadly about the future form of the grid and the process of making almost all energy renewable. Sun, who in 2022 rejoined MIT as the Iberdrola-Avangrid Associate Professor in Electric Power Systems, and is also an associate professor of operations research, emphasizes the urgency of rapidly switching to renewables.

    “The decarbonization of our energy system is fundamental,” Sun says. “It will change a lot of things because it has to. We don’t have much time to get there. Two decades, three decades is the window in which we have to get a lot of things done. If you think about how much money will need to be invested, it’s not actually that much. We should embrace this future that we have to get to.”

    Successful operations

    Unexpected as it may have been, Sun’s journey toward being an electricity grid expert was informed by all the stages of his higher education. Sun grew up in China, and received his BA in electronic engineering from Tsinghua University in Beijing, in 2003. He then moved to MIT, joining the Media Lab as a graduate student. Sun intended to study quantum computing but instead began working on analog computer circuit design for Professor Neil Gershenfeld, another person whose worldview influenced Sun.  

    “He had this vision about how optimization is very important in things,” Sun says. “I had never heard of optimization before.” 

    To learn more about it, Sun started taking MIT courses in operations research. “I really enjoyed it, especially the nonlinear optimization course taught by Robert Freund in the Operations Research Center,” he recalls. 

    Sun enjoyed it so much that after a while, he joined MIT’s PhD program in operations research, thanks to the guidance of Freund. Later, he started working with MIT Sloan Professor Dimitri Bertsimas, a leading figure in the field. Still, Sun hadn’t quite nailed down what he wanted to focus on within operations research. Thinking of Sun’s engineering skills, Bertsimas suggested that Sun look for a research topic related to energy. 

    “He wasn’t an expert in energy at that time, but he knew that there are important problems there and encouraged me to go ahead and learn,” Sun says. 

    So it was that Sun found himself in ISO-New England headquarters one day in 2007, finally knowing what he wanted to study, and quickly finding opportunities to start learning from the organization’s experts on electricity markets. By 2011, Sun had finished his MIT PhD dissertation. Based in part on ISO-New England data, the thesis presented new modeling to more efficiently integrate renewable energy into the grid; built some new modeling tools grid operators could use; and developed a way to add fair short-term energy auctions to an efficient grid system.

    The core problem Sun deals with is that, unlike some other sources of electricity, renewables tend to be intermittent, generating power in an uneven pattern over time. That’s not an insurmountable problem for grid operators, but it does require some new approaches. Many of the papers Sun has written focus on precisely how to increasingly draw upon intermittent energy sources while ensuring that the grid’s current level of functionality remains intact. This is also the focus of his 2021 book, co-authored with Antonio J. Conejo, “Robust Optimiziation in Electric Energy Systems.”

    “A major theme of my research is how to achieve the integration of renewables and still operate the system reliably,” Sun says. “You have to keep the balance of supply and demand. This requires many time scales of operation from multidecade planning, to monthly or annual maintenance, to daily operations, down through second-by-second. I work on problems in all these timescales.”

    “I sit in the interface between power engineering and operations research,” Sun says. “I’m not a power engineer, but I sit in this boundary, and I keep the problems in optimization as my motivation.”

    Culture shift

    Sun’s presence on the MIT campus represents a homecoming of sorts. After receiving his doctorate from MIT, Sun spent a year as a postdoc at IBM’s Thomas J. Watson Research Center, then joined the faculty at Georgia Tech, where he remained for a decade. He returned to the Institute in January of 2022.

    “I’m just very excited about the opportunity of being back at MIT,” Sun says. “The MIT Energy Initiative is a such a vibrant place, where many people come together to work on energy. I sit in Sloan, but one very strong point of MIT is there are not many barriers, institutionally. I really look forward to working with colleagues from engineering, Sloan, everywhere, moving forward. We’re moving in the right direction, with a lot of people coming together to break the traditional academic boundaries.” 

    Still, Sun warns that some people may be underestimating the severity of the challenge ahead and the need to implement changes right now. The assets in power grids have long life time, lasting multiple decades. That means investment decisions made now could affect how much clean power is being used a generation from now. 

    “We’re talking about a short timeline, for changing something as huge as how a society fundamentally powers itself with energy,” Sun says. “A lot of that must come from the technology we have today. Renewables are becoming much better and cheaper, so their use has to go up.”

    And that means more people need to work on issues of how to deploy and integrate renewables into everyday life, in the electric grid, transportation, and more. Sun hopes people will increasingly recognize energy as a huge growth area for research and applied work. For instance, when MIT President Sally Kornbluth gave her inaugural address on May 1 this year, she emphasized tackling the climate crisis as her highest priority, something Sun noticed and applauded. 

    “I think the most important thing is the culture,” Sun says. “Bring climate up to the front, and create the platform to encourage people to come together and work on this issue.” More

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    The curse of variety in transportation systems

    Cathy Wu has always delighted in systems that run smoothly. In high school, she designed a project to optimize the best route for getting to class on time. Her research interests and career track are evidence of a propensity for organizing and optimizing, coupled with a strong sense of responsibility to contribute to society instilled by her parents at a young age.

    As an undergraduate at MIT, Wu explored domains like agriculture, energy, and education, eventually homing in on transportation. “Transportation touches each of our lives,” she says. “Every day, we experience the inefficiencies and safety issues as well as the environmental harms associated with our transportation systems. I believe we can and should do better.”

    But doing so is complicated. Consider the long-standing issue of traffic systems control. Wu explains that it is not one problem, but more accurately a family of control problems impacted by variables like time of day, weather, and vehicle type — not to mention the types of sensing and communication technologies used to measure roadway information. Every differentiating factor introduces an exponentially larger set of control problems. There are thousands of control-problem variations and hundreds, if not thousands, of studies and papers dedicated to each problem. Wu refers to the sheer number of variations as the curse of variety — and it is hindering innovation.

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    “To prove that a new control strategy can be safely deployed on our streets can take years. As time lags, we lose opportunities to improve safety and equity while mitigating environmental impacts. Accelerating this process has huge potential,” says Wu.  

    Which is why she and her group in the MIT Laboratory for Information and Decision Systems are devising machine learning-based methods to solve not just a single control problem or a single optimization problem, but families of control and optimization problems at scale. “In our case, we’re examining emerging transportation problems that people have spent decades trying to solve with classical approaches. It seems to me that we need a different approach.”

    Optimizing intersections

    Currently, Wu’s largest research endeavor is called Project Greenwave. There are many sectors that directly contribute to climate change, but transportation is responsible for the largest share of greenhouse gas emissions — 29 percent, of which 81 percent is due to land transportation. And while much of the conversation around mitigating environmental impacts related to mobility is focused on electric vehicles (EVs), electrification has its drawbacks. EV fleet turnover is time-consuming (“on the order of decades,” says Wu), and limited global access to the technology presents a significant barrier to widespread adoption.

    Wu’s research, on the other hand, addresses traffic control problems by leveraging deep reinforcement learning. Specifically, she is looking at traffic intersections — and for good reason. In the United States alone, there are more than 300,000 signalized intersections where vehicles must stop or slow down before re-accelerating. And every re-acceleration burns fossil fuels and contributes to greenhouse gas emissions.

    Highlighting the magnitude of the issue, Wu says, “We have done preliminary analysis indicating that up to 15 percent of land transportation CO2 is wasted through energy spent idling and re-accelerating at intersections.”

    To date, she and her group have modeled 30,000 different intersections across 10 major metropolitan areas in the United States. That is 30,000 different configurations, roadway topologies (e.g., grade of road or elevation), different weather conditions, and variations in travel demand and fuel mix. Each intersection and its corresponding scenarios represents a unique multi-agent control problem.

    Wu and her team are devising techniques that can solve not just one, but a whole family of problems comprised of tens of thousands of scenarios. Put simply, the idea is to coordinate the timing of vehicles so they arrive at intersections when traffic lights are green, thereby eliminating the start, stop, re-accelerate conundrum. Along the way, they are building an ecosystem of tools, datasets, and methods to enable roadway interventions and impact assessments of strategies to significantly reduce carbon-intense urban driving.

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    Their collaborator on the project is the Utah Department of Transportation, which Wu says has played an essential role, in part by sharing data and practical knowledge that she and her group otherwise would not have been able to access publicly.

    “I appreciate industry and public sector collaborations,” says Wu. “When it comes to important societal problems, one really needs grounding with practitioners. One needs to be able to hear the perspectives in the field. My interactions with practitioners expand my horizons and help ground my research. You never know when you’ll hear the perspective that is the key to the solution, or perhaps the key to understanding the problem.”

    Finding the best routes

    In a similar vein, she and her research group are tackling large coordination problems. For example, vehicle routing. “Every day, delivery trucks route more than a hundred thousand packages for the city of Boston alone,” says Wu. Accomplishing the task requires, among other things, figuring out which trucks to use, which packages to deliver, and the order in which to deliver them as efficiently as possible. If and when the trucks are electrified, they will need to be charged, adding another wrinkle to the process and further complicating route optimization.

    The vehicle routing problem, and therefore the scope of Wu’s work, extends beyond truck routing for package delivery. Ride-hailing cars may need to pick up objects as well as drop them off; and what if delivery is done by bicycle or drone? In partnership with Amazon, for example, Wu and her team addressed routing and path planning for hundreds of robots (up to 800) in their warehouses.

    Every variation requires custom heuristics that are expensive and time-consuming to develop. Again, this is really a family of problems — each one complicated, time-consuming, and currently unsolved by classical techniques — and they are all variations of a central routing problem. The curse of variety meets operations and logistics.

    By combining classical approaches with modern deep-learning methods, Wu is looking for a way to automatically identify heuristics that can effectively solve all of these vehicle routing problems. So far, her approach has proved successful.

    “We’ve contributed hybrid learning approaches that take existing solution methods for small problems and incorporate them into our learning framework to scale and accelerate that existing solver for large problems. And we’re able to do this in a way that can automatically identify heuristics for specialized variations of the vehicle routing problem.” The next step, says Wu, is applying a similar approach to multi-agent robotics problems in automated warehouses.

    Wu and her group are making big strides, in part due to their dedication to use-inspired basic research. Rather than applying known methods or science to a problem, they develop new methods, new science, to address problems. The methods she and her team employ are necessitated by societal problems with practical implications. The inspiration for the approach? None other than Louis Pasteur, who described his research style in a now-famous article titled “Pasteur’s Quadrant.” Anthrax was decimating the sheep population, and Pasteur wanted to better understand why and what could be done about it. The tools of the time could not solve the problem, so he invented a new field, microbiology, not out of curiosity but out of necessity. More

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    Making sense of all things data

    Data, and more specifically using data, is not a new concept, but it remains an elusive one. It comes with terms like “the internet of things” (IoT) and “the cloud,” and no matter how often those are explained, smart people can still be confused. And then there’s the amount of information available and the speed with which it comes in. Software is omnipresent. It’s in coffeemakers and watches, gathering data every second. The question becomes how to take all the new technology and take advantage of the potential insights and analytics. It’s not a small ask.

    “Putting our arms around what digital transformation is can be difficult to do,” says Abel Sanchez. But as the executive director and research director of MIT’s Geospatial Data Center, that’s exactly what he does with his work in helping industries and executives shift their operations in order to make sense of their data and be able to use it to help their bottom lines.

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    Handling the pace

    Data can lead to making better business decisions. That’s not a new or surprising insight, but as Sanchez says, people still tend to work off of intuition. Part of the problem is that they don’t know what to do with their available data, and there’s usually plenty of available data. Part of that problem is that there’s so much information being produced from so many sources. As soon as a person wakes up and turns on their phone or starts their car, software is running. It’s coming in fast, but because it’s also complex, “it outperforms people,” he says.

    As an example with Uber, once a person clicks on the app for a ride, predictive models start firing at the rate of 1 million per second. It’s all in order to optimize the trip, taking into account factors such as school schedules, roadway conditions, traffic, and a driver’s availability. It’s helpful for the task, but it’s something that “no human would be able to do,” he says. 

    The solution requires a few components. One is a new way to store data. In the past, the classic was creating the “perfect library,” which was too structured. The response to that was to create a “data lake,” where all the information would go in and somehow people would make sense of it. “This also failed,” Sanchez says.

    Data storage needs to be re-imaged, in which a key element is greater accessibility. In most corporations, only 10-20 percent of employees have the access and technical skill to work with the data. The rest have to go through a centralized resource and get into a queue, an inefficient system. The goal, Sanchez says, is to democratize the information by going to a modern stack, which would convert what he calls “dormant data” into “active data.” The result? Better decisions could be made.

    The first, big step companies need to take is the will to make the change. Part of it is an investment of money, but it’s also an attitude shift. Corporations can have an embedded culture where things have always been done a certain way and deviating from that is resisted because it’s different. But when it comes to data, a new approach is needed. Managing and curating the information can no longer rest in the hands of one person with the institutional memory. It’s not possible. It’s also not practical because companies are losing out on efficiency and productivity, because with technology, “What use to take years to do, now you can do in days,” Sanchez says.

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    The new player

    The above exemplifies what’s been involved with coordinating data along four intertwined components: IoT, AI, the cloud, and security. The first two create the information, which then gets stored in the cloud, but it’s all for naught without robust security. But one relative newcomer has come into the picture. It’s blockchain technology, a term that is often said but still not fully understood, adding further to the confusion.

    Sanchez says that information has been handled and organized a certain way with the World Wide Web. Blockchain is an opportunity to be more nimble and productive by offering the chance to have an accepted identity, currency, and logic that works on a global scale. The holdup has always been that there’s never been any agreement on those three components on a global scale. It leads to people being shut out, inefficiency, and lost business.

    One example, Sanchez says, of blockchain’s potential is with hospitals. In the United States, they’re private and information has to be constantly integrated from doctors, insurance companies, labs, government regulators, and pharmaceutical companies. It leads to repeated steps to do something as simple as recognizing a patient’s identity, which often can’t be agreed upon. With blockchain, these various entities can create a consortium using open source code with no barriers of access, and it could quickly and easily identify a patient because it set up an agreement, and with it “remove that level of effort.” It’s an incremental step, but one which can be built upon that reduces cost and risk.

    Another example — “one of the best examples,” Sanchez says — is what was done in Indonesia. Most of the rice, corn, and wheat that comes from this area is produced from smallholder farms. For the people making loans, it’s expensive to understand the risk of cultivating these plots of land. Compounding that is that these farmers don’t have state-issued identities or credit records, so, “They don’t exist in the modern economic sense,” he says. They don’t have access to loans, and banks are losing out on potential good customers.

    With this project, blockchain allowed local people to gather information about the farms on their smartphones. Banks could acquire the information and compensate the people with tokens, thereby incentivizing the work. The bank would see the creditworthiness of the farms, and farmers could end up getting fair loans.

    In the end, it creates a beneficial circle for the banks, farmers, and community, but it also represents what can be done with digital transformation by allowing businesses to optimize their processes, make better decisions, and ultimately profit.

    “It’s a tremendous new platform,” Sanchez says. “This is the promise.” More