News in Briefs

L. Rafael Reif, a distinguished electrical engineer whose seven-year tenure as MIT’s provost has helped MIT maintain its appetite for bold action as well as its firm financial footing, has been selected as the 17th president of the Institute.

Reif, 61, was elected to the post this morning by a vote of the MIT Corporation. He will assume the MIT presidency on July 2.

President-elect L. Rafael Reif
Photo: Dominick Reuter

As the Institute’s chief academic officer since 2005, Reif led the design and implementation of the strategy that allowed MIT to weather the global financial crisis; drove the growth of MIT’s global strategy; promoted a major faculty-led effort to address challenges around race and diversity; helped foster the emergence of an innovation cluster adjacent to MIT in Kendall Square; led the development of MITx, the Institute’s new initiative in online learning; and led MIT’s role in the formation of edX, the recently announced partnership between MIT and Harvard University that builds on MITx and that aims to enrich residential education while bringing online learning to great numbers of people around the world.

Reif has been a member of the MIT faculty since 1980 and is currently the Fariborz Maseeh Professor of Emerging Technology in the Department of Electrical Engineering and Computer Science. He succeeds Susan Hockfield, who announced earlier this year that she would step down after more than seven years as MIT’s president.

A rich candidate pool gained from ‘especially broad outreach’

Reif’s selection as MIT’s next president follows broad consultation with students, faculty, staff, alumni, and friends of MIT. Through outreach via multiple channels, a 22-member Presidential Search Committee generated a list of more than 100 candidates for the presidency. That list included people identified by the committee itself as well as those suggested by others; members of the MIT community and people outside the Institute; and candidates with a broad range of backgrounds in academia and beyond.

“The search committee has done excellent, thorough work that not only resulted in an outstanding outcome, but also in a great feeling of community among the wide-ranging group of people who helped us in our search,” said MIT Corporation Chairman John S. Reed ’61. “Rafael Reif emerged early as a uniquely qualified candidate, and that impression only deepened as our discussions with him and with members of the MIT community proceeded. Rafael brings with him a career as a distinguished engineer and a gifted administrator, and his 30 years of achievement at MIT speak to a profound dedication to, and understanding of, the Institute.”

The Presidential Search Committee was chaired by James A. Champy ’63, SM ’65, a Boston business consultant and author; Champy also led the 2004 presidential search that culminated in Hockfield’s selection.

“The committee’s intense and thorough process included especially broad outreach,” Champy said. “The committee sought input not only from faculty and students, but also from staff. As a result of this rich internal input as well as input from voices outside MIT, we had an excellent pool. As a hundred became dozens, and dozens a small handful, one name kept coming up. In discussing Rafael’s candidacy with key members of the MIT community, we heard not only about Rafael’s impressive record of achievement in service to the Institute, but also about people’s enthusiastic support for him as a leader fully engaged with the MIT community. The committee members are overjoyed by Rafael’s election.”

An accomplished provost

As provost, Reif has held overarching responsibility for MIT’s educational and research programs, as well as for the recruitment, promotion and tenuring of faculty. He has worked closely with the deans of MIT’s five schools to establish academic priorities and with the executive vice president to manage the financial planning to support these priorities. Also in his role as provost, Reif has oversight responsibility for Lincoln Laboratory (a research laboratory that MIT operates for the U.S. Department of Defense), as well as for the Institute’s libraries and a number of major interdisciplinary laboratories, centers and programs.

Reif played a critical role in balancing MIT’s budget before, during and after the global financial crisis. Early in his tenure as provost, he led a “rebalancing” process that eliminated a $50 million structural deficit — putting the Institute in a much better position to weather the global downturn that began in 2008. Then, after the crisis struck, Reif led the team that designed and implemented the strategy for managing budget cuts. Among other steps, a 200-member Institute-wide Planning Task Force ultimately achieved significant long-term cost reductions by acting upon 77 percent of all ideas submitted by members of the MIT community.

As provost, Reif propelled a global strategy that has seen the Institute partner with governments and foundations to create four new research centers and universities worldwide. In 2007, MIT assisted in the creation of the Masdar Institute of Science and Technology in Abu Dhabi, a graduate educational and research institute devoted to advanced energy and sustainable technologies. Since 2008, Reif and other Institute officials have partnered with Singapore’s government to establish two new institutions: the Singapore-MIT Alliance for Research and Technology Centre and the Singapore University of Technology and Design, whose first class of students matriculated earlier this month. Last fall, MIT joined in the creation of the Skolkovo Institute of Science and Technology in Russia, envisioned as a unique, world-class graduate research university.

Starting in 2007, Reif promoted a major faculty-led effort to address challenges around race and diversity, convening a faculty committee to investigate impediments to MIT’s recruitment and retention of minority faculty. The committee ultimately concluded that while efforts to hire and retain minority faculty had produced some gains, the experience of minority faculty at the Institute differed from that of their majority peers. Reif has since taken steps to foster a culture of inclusion at the Institute, taking a personal interest in recruiting and retention efforts for minorities and women.  To help with these efforts, Reif established the Office of the Associate Provost for Faculty Equity.

President-elect L. Rafael Reif at the May 2 press conference announcing edX.
Photo: Allegra Boverman

Finally, Reif led a five-year project to develop a new paradigm in online learning. These efforts came to fruition with last December’s launch of MITx: a pioneering online-education initiative designed to bring new tools to students at MIT and to offer MIT content online to learners around the world, for free, through an interactive, open-source learning platform. MITx’s initial offering — an online course called “Circuits and Electronics” — has enrolled more than 120,000 students from around the world. Reif’s vision of exploring how online learning tools can improve residential education, as well as his interest in broadly accessible, high-caliber online courses, was further advanced earlier this month with the creation of edX, a $60 million online-education partnership with Harvard University. Reif led MIT’s entrance into that significant partnership.

“During my presidency,” Hockfield said, “our provost, Professor Rafael Reif, has been a true and trusted partner. I and the global MIT community have benefited immensely not only from his brilliant leadership of major initiatives, such as our international engagements and the MITx and edX launches, but also from the vital role he has played in stewarding the Institute’s finances and capital planning during a time of global financial uncertainty. His leadership in establishing the Institute-wide Budget Planning Task Force, which so brilliantly tapped the creativity and dedication of the MIT community, brought forth the very best of MIT. The Institute today finds itself both sure- and swift-footed, thanks in great part to Rafael’s strategic intelligence and dedication. I am enormously pleased by his election, knowing he will serve the Institute as president with devotion, insight and compassion.”

A citizen of the world

Leo Rafael Reif (pronounced “rife”) is the youngest of four sons of Eastern European emigrés who fled Europe in the late 1930s, living first in Ecuador and then Colombia before settling in Venezuela. The family was poor, supported by his father’s work as a photographer, and spoke Spanish and Yiddish at home.

Reif was born in Maracaibo, Venezuela, and moved to Caracas with his family at age 9. A member of the first generation in his family to attend college, he earned his undergraduate degree in electrical engineering from Venezuela’s Universidad de Carabobo in 1973. After working for one year as an assistant professor at Universidad Simón Bolívar, he left for graduate school in the United States. Despite speaking little English upon his arrival at Stanford University in 1974, he earned an MS in electrical engineering the following year and completed his PhD in electrical engineering in 1979.

Reif joined MIT in January 1980 as an assistant professor of electrical engineering. He was promoted to associate professor in 1983, earned tenure in 1985, and became a full professor in 1988.

“I am deeply honored to be elected president of the Institute I love so dearly,” Reif said. “MIT’s impact on my life — how I think, how I make sense of the world, and how I align my personal aspirations with the call to service — has been profound. The Institute has never failed to challenge, invigorate and inspire me: I have found that one of its most stimulating characteristics is that it always feels new. As I begin to comprehend the humbling responsibility with which the Institute has entrusted me, the ‘I’ becomes a ‘we’: The true strength of MIT leadership has always come from the power of the MIT community, whose collective wisdom, talent, creativity and drive have made history for 150 years. I am thrilled to think of the work we will do together for — quoting from our mission statement — ‘the betterment of humankind.’”

A longtime leader at MIT

The president-elect has held leadership posts for much of his time on the MIT faculty. From 1990 to 1999, Reif was director of MIT’s Microsystems Technology Laboratories, an interdepartmental laboratory supporting research and education in microscale and nanoscale systems. He then served as associate head of the Department of Electrical Engineering and Computer Science — MIT’s largest academic department — from 1999 to 2004, and chaired the department before becoming provost in August 2005.

An early champion of MIT’s engagement in micro- and nanotechnologies, Reif was instrumental in launching a research center on novel semiconductor devices at MIT, as well as multi-university research centers on advanced and environmentally benign semiconductor manufacturing. He also played a key role in creating the national effort now known as the Focus Center Research Program and in launching its Interconnect Focus Center.

Samuel M. Allen, the POSCO Professor of Physical Metallurgy in the Department of Materials Science and Engineering and the Chair of the MIT Faculty, said, “Professor Reif is widely admired for his integrity, knowledge of MIT and vision for the future. His leadership during the 2008 financial squeeze, and his vision for the evolution of residential education in the digital age, are tangible signs of his ability to mobilize the community in major endeavors. From my vantage point as Chair of the Faculty, I know that Rafael seeks faculty input in making important decisions, and he is open to embracing new ideas. I’m excited to have the opportunity to work closely with him in the coming year.”

A leader in microelectronics

Reif is internationally recognized as a leading microelectronics researcher who has helped address the technical challenges that have arisen as electronics have grown ever-smaller in recent decades. He did pioneering work in and was an early proponent of three-dimensional integrated circuits, in which layers fabricated through different processes are stacked to form complex monolithic systems. Such an approach allows the integration of a variety of electronic functionalities into a smaller chip area.

Reif’s group has also worked to identify and develop environmentally benign alternatives to chemicals used to etch patterns on microchips; some gases used heavily by the semiconductor industry were believed to contribute to global warming. His team has worked to assess the etching efficacy of a variety of alternative compounds, measuring the effluents of these processes to determine their potential environmental, safety and health impacts.

A prolific scholar

Reif holds 15 patents, has edited or co-edited five books, has supervised 38 doctoral theses, and is a co-author of more than 350 papers published in refereed journals and conference proceedings.

In 1993 Reif was named a fellow of the Institute of Electrical and Electronics Engineers (IEEE) “for pioneering work in the low-temperature epitaxial growth of semiconductor thin films.” From the Semiconductor Research Corporation (SRC), he received the 2000 Aristotle Award for “his commitment to the educational experience of SRC students and the profound and continuing impact he has had on their professional careers.” He is a member of Tau Beta Pi, the Electrochemical Society and the IEEE. For his work in developing MITx, he received the 2012 Tribeca Disruptive Innovation Award.

Reif and his wife, Christine, are residents of Newton, Mass. They have a daughter, Jessica Reif Caplan, a son-in-law, Benjamin Caplan, and a son, Blake Harrington.

By web.mit.edu

In its early years, information theory — which grew out of a landmark 1948 paper by MIT alumnus and future professor Claude Shannon — was dominated by research on error-correcting codes: How do you encode information so as to guarantee its faithful transmission, even in the presence of the corrupting influences engineers call “noise”?

Recently, one of the most intriguing developments in information theory has been a different kind of coding, called network coding, in which the question is how to encode information in order to maximize the capacity of a network as a whole. For information theorists, it was natural to ask how these two types of coding might be combined: If you want to both minimize error and maximize capacity, which kind of coding do you apply where, and when do you do the decoding?

What makes that question particularly hard to answer is that no one knows how to calculate the data capacity of a network as a whole — or even whether it can be calculated. Nonetheless, in the first half of a two-part paper, which was published recently in IEEE Transactions on Information Theory, MIT’s Muriel Médard, California Institute of Technology’s Michelle Effros and the late Ralf Koetter of the University of Technology in Munich show that in a wired network, network coding and error-correcting coding can be handled separately, without reduction in the network’s capacity. In the forthcoming second half of the paper, the same researchers demonstrate some bounds on the capacities of wireless networks, which could help guide future research in both industry and academia.

A typical data network consists of an array of nodes — which could be routers on the Internet, wireless base stations or even processing units on a single chip — each of which can directly communicate with a handful of its neighbors. When a packet of data arrives at a node, the node inspects its addressing information and decides which of several pathways to send it along.

Calculated confusion

With network coding, on the other hand, a node scrambles together the packets it receives and sends the hybrid packets down multiple paths; at each subsequent node they’re scrambled again in different ways. Counterintuitively, this can significantly increase the capacity of the network as a whole: Hybrid packets arrive at their destination along multiple paths. If one of those paths is congested, or if one of its links fails outright, the packets arriving via the other paths will probably contain enough information that the recipient can piece together the original message.

But each link between nodes could be noisy, so the information in the packets also needs to be encoded to correct for errors. “Suppose that I’m a node in a network, and I see a communication coming in, and it is corrupted by noise,” says Médard, a professor of electrical engineering and computer science. “I could try to remove the noise, but by doing that, I’m in effect making a decision right now that maybe would have been better taken by someone downstream from me who might have had more observations of the same source.”

On the other hand, Médard says, if a node simply forwards the data it receives without performing any error correction, it could end up squandering bandwidth. “If the node takes all the signal it has and does not whittle down his representation, then it might be using a lot of energy to transmit noise,” she says. “The question is, how much of the noise do I remove, and how much do I leave in?”

In their first paper, Médard and her colleagues analyze the case in which the noise in a given link is unrelated to the signals traveling over other links, as is true of most wired networks. In that case, the researchers show, the problems of error correction and network coding can be separated without limiting the capacity of the network as a whole.

Noisy neighbors

In the second paper, the researchers tackle the case in which the noise on a given link is related to the signals on other links, as is true of most wireless networks, since the transmissions of neighboring base stations can interfere with each other. This complicates things enormously: Indeed, Médard points out, information theorists still don’t know how to quantify the capacity of a simple three-node wireless network, in which two nodes relay messages to each other via a third node.

Nonetheless, Médard and her colleagues show how to calculate upper and lower bounds on the capacity of a given wireless network. While the gap between the bounds can be very large in practice, knowing the bounds could still help network operators evaluate the benefits of further research on network coding. If the observed bit rate on a real-world network is below the lower bound, the operator knows the minimum improvement that the ideal code would provide; if the observed rate is above the lower bound but below the upper, then the operator knows the maximum improvement that the ideal code might provide. If even the maximum improvement would afford only a small savings in operational expenses, the operator may decide that further research on improved coding isn’t worth the money.

“The separation theorem they proved is of fundamental interest,” says Raymond Yeung, a professor of information engineering and co-director of the Institute of Network Coding at the Chinese University of Hong Kong. “While the result itself is not surprising, it is somewhat unexpected that they were able to prove the result in such a general setting.”

Yeung cautions, however, that while the researchers have “decomposed a very difficult problem into two,” one of those problems “remains very difficult. … The bound is in terms of the solution to another problem which is difficult to solve,” he says. “It is not clear how tight this bound is; that needs further research.”

By web.mit.edu

Earlier this year, Professors and CSAIL Principal Investigators Piotr Indyk and Dina Katabi, along with CSAIL graduate students Haitham Hassanieh and Eric Price, announced that they had improved upon the Fourier transform, an algorithm for processing streams of data. Their new algorithm, called the sparse Fourier transform (SFT), has been named to MIT Technology Review’s 2012 list of the world’s 10 most important emerging technologies.

With the SFT algorithm, streams of data can be processed 10 to 100 times faster than was possible before, allowing for a speedier and more efficient digital world.

“We selected the sparse Fourier transform developed by Dina Katabi, Haitham Hassanieh, Piotr Indyk and Eric Price as one of the 10 most important technology milestones of the past year because we expect it to have a significant impact,” said Brian Bergstein, Technology Review’s deputy editor. “By decreasing the amount of computation required to process information, this algorithm should make our devices and networks more powerful.”

Each year, the editors of MIT Technology Review select the 10 emerging technologies with the greatest potential to transform our world. These innovations promise fundamental shifts in areas including energy, health care, computing and communications. The SFT is featured in the May/June edition of Technology Review and is posted on the web at http://www.technologyreview.com/tr10/.

By web.mit.edu

In the last 10 years, cryptography researchers have demonstrated that even the most secure-seeming computer is shockingly vulnerable to attack. The time it takes a computer to store data in memory, fluctuations in its power consumption and even the noises it emits can betray information to a savvy assailant.

Attacks that use such indirect sources of information are called side-channel attacks, and the increasing popularity of cloud computing makes them an even greater threat. An attacker would have to be pretty motivated to install a device in your wall to measure your computer’s power consumption. But it’s comparatively easy to load a bit of code on a server in the cloud and eavesdrop on other applications it’s running.

Fortunately, even as they’ve been researching side-channel attacks, cryptographers have also been investigating ways of stopping them. Shafi Goldwasser, the RSA Professor of Electrical Engineering and Computer Science at MIT, and her former student Guy Rothblum, who’s now a researcher at Microsoft Research, recently posted a long report on the website of the Electronic Colloquium on Computational Complexity, describing a general approach to mitigating side-channel attacks. At the Association for Computing Machinery’s Symposium on Theory of Computing (STOC) in May, Goldwasser and colleagues will present a paper demonstrating how the technique she developed with Rothblum can be adapted to protect information processed on web servers.

In addition to preventing attacks on private information, Goldwasser says, the technique could also protect devices that use proprietary algorithms so that they can’t be reverse-engineered by pirates or market competitors — an application that she, Rothblum and others described at last year’s AsiaCrypt conference.

Today, when a personal computer is in use, it’s usually running multiple programs — say, a word processor, a browser, a PDF viewer, maybe an email program or a spreadsheet program. All the programs are storing data in memory, but the laptop’s operating system won’t let any program look at the data stored by any other. The operating systems running on servers in the cloud are no different, but a malicious program could launch a side-channel attack simply by sending its own data to memory over and over again. From the time the data storage and retrieval takes, it can infer what the other programs are doing with remarkable accuracy.

Goldwasser and Rothblum’s technique obscures the computational details of a program, whether it’s running on a laptop or a server. Their system converts a given computation into a sequence of smaller computational modules. Data fed into the first module is encrypted, and at no point during the module’s execution is it decrypted. The still-encrypted output of the first module is fed into the second module, which encrypts it in yet a different way, and so on.

The encryption schemes and the modules are devised so that the output of the final module is exactly the output of the original computation. But the operations performed by the individual modules are entirely different. A side-channel attacker could extract information about how the data in any given module is encrypted, but that won’t let him deduce what the sequence of modules do as a whole. “The adversary can take measurements of each module,” Goldwasser says, “but they can’t learn anything more than they could from a black box.”

The report by Goldwasser and Rothblum describes a type of compiler, a program that takes code written in a form intelligible to humans and converts it into the low-level instruction intelligible to a computer. There, the computational modules are an abstraction: The instruction that inaugurates a new module looks no different from the instruction that concluded the last one. But in the STOC paper, the modules are executed on different servers on a network.

According to Nigel Smart, a professor of cryptology in the computer science department at the University of Bristol in England, the danger of side-channel attacks “has been known since the late ’90s.”

“There’s a lot of engineering that was done to try to prevent this from being a problem,” Smart says, “a huge amount of engineering work. This is a megabucks industry.” Much of that work, however, has relied on trial and error, Smart says. Goldwasser and Rothblum’s study, on the other hand, “is a much more foundational study, looking at really foundational, deep questions about what is possible.”

Moreover, Smart says, previous work on side-channel attacks tended to focus on the threat posed to handheld devices, such as cellphones and smart cards. “It would seem to me that the stuff that is more likely to take off in the long run is the stuff that’s talking about servers,” Smart says. “I don’t know anyone else outside MIT who’s looking at that.”

Smart cautions, however, that the work of Goldwasser and her colleagues is unlikely to yield practical applications in the near future. “In security, and especially cryptography, it takes a long time to go from an academic idea to something that’s actually used in the real world,” Smart says. “They’re looking at what could be possible in 10, 20 years’ time.”

By web.mit.edu

Hal Abelson has been honored by the Association for Computing Machinery (ACM) with the Karl V. Karlstom Outstanding Educator Award for his contributions to computer science education. Abelson is the Class of 1922 Professor of Electrical Engineering and Computer Science at MIT, a principal investigator at the MIT Computer Science and Artificial Intelligence Laboratory (CSAIL) and co-chair of the MIT Council on Educational Technology.

For Abelson, being honored for his work as an educator is a crowning achievement.

“Of all the ways to be honored, for me education is the one that really means the most,” Abelson says. “That’s how I think of myself at MIT, as a teacher.”

Abelson was honored by the ACM for innovative advances in curricula designed for students pursuing different kinds of computing expertise. Along with Professor Gerry Sussman (also a principal investigator at CSAIL), Abelson developed MIT’s introductory computer science course, “Structure and Interpretation of Computer Programs.” The course was revolutionary in that it introduced a new method for teaching computer science that de-emphasized programming language specifics and concentrated on the mathematical idea of abstraction as a fundamental concept in programming.

Throughout his career, Abelson has been dedicated to democratizing access to education through computer science. Through his work with the MIT Council on Educational Technology, he played a key role in launching MIT OpenCourseWare, a web-based publication of MIT course content accessible to all, and D-Space, MIT’s online repository of digital research materials, with the goal of using the Internet to provide equal access to the learning and education underway at universities.

Abelson is currently working on a new tool called App Inventor, which allows individuals with no computer science background to program and develop mobile applications. With this technology, Abelson’s goal is to empower all individuals — and children in particular — by giving them the ability to contribute to the creation of new technologies. Through App Inventor, people around the world have developed a wide variety of new programs, from applications that remind people not to text while driving to an application created by students in Arkansas that tracks wild hog sightings.

Abelson’s interest in providing children with access to technology was inspired by his work as a graduate student at MIT on the Logo Programming Language, which was designed as a tool for educating children. In the same way that he was inspired to put computers into the hands of children in the 1970s, today Abelson hopes to make mobile computing available to all.

According to Abelson, “App Inventor takes that sense of empowerment, that notion of, ‘Why shouldn’t 12-year-olds be in control of mobile phones or tablets or the next branch of mobile technology?’ There are real opportunities for computer science to have an impact on education in the future.”

Abelson is a fellow of the IEEE and is co-director of MIT’s Center for Mobile Learning. He received MIT’s Bose Award, the IEEE Computer Society Taylor L. Booth Education Award for continued contributions to the pedagogy and teaching of introductory computer science, and the ACM Special Interest Group on Computer Science Education (SIGCSE) Award for outstanding contributions to computer science education.

The Karl V. Karlstom Outstanding Educator Award is presented annually to an outstanding educator who is appointed to a recognized educational baccalaureate institution. The recipient is recognized for advancing new teaching methodologies; effecting new curriculum development or expansion in computer science and engineering; or making a significant contribution to the educational mission of ACM. A prize of $5,000 is supplied by Pearson Education.

The ACM will present this award at the ACM Awards Banquet on June 16 in San Francisco.

By web.mit.edu

What’s it like taking a course with 120,000 other students?

That is one of the questions raised this spring by the debut of MITx, the Institute’s new online educational initiative. The first offering — a course dubbed 6.002x, or “Circuits and Electronics” — is running from March 5 through June 8, modeled after one of the introductory courses taught in MIT’s Department of Electrical Engineering and Computer Science (EECS).

Some people taking 6.002x are students at other universities who are using the course to supplement their own educations; others are professionals whose long-running interest in the subject has been fired anew by the course. MIT News recently canvassed students from around the world who are enrolled in 6.002x to see what their experience has been like — so far, at any rate.

INFOGRAPHIC: 6.002x students, in their own words

Myriam Nonaka, an electrical engineering student at the Universidad Tecnológica Nacional in Buenos Aires, Argentina, finds 6.002x to be “very entertaining,” and singles out the course’s online discussion forum as a place “where you can share and learn.” Indeed, the forum, where students discuss the course and offer assistance to each other, is something that almost all MITx participants cite as a defining feature of the experience.

For Gerardo Muñoz Coronel, an electrical engineering student from Querétaro, Mexico, it’s “exciting … to develop new skills with the support of a virtual-campus community.” Since starting the course, he has interacted in the forum with “nice online classmates” from Australia, Colombia, England, India and Kenya, among other places.

Many of those taking 6.002x already have degrees, and are using the course to sharpen skills for personal or professional reasons. Brian Ho, the owner of a software-development company in Honolulu who has a long-running interest in robotics, has an electrical engineering degree and is using the course to “refresh” his knowledge of the subject.

“We are learning to think intuitively when approaching electrical engineering — an intuition I didn’t have before,” Ho explains. As far as the discussion forums go, he adds, “I equally enjoy helping other students … in the process of helping others, you are actually helping yourself because in order to explain a concept perfectly you really need to understand the subject.”

‘Personally … it means a lot’

Course 6.002x is being co-taught by Anant Agarwal, a professor in EECS and director of MIT’s Computer Science and Artificial Intelligence Laboratory (CSAIL); Chris Terman, co-director of CSAIL; Gerald Sussman, the Panasonic Professor of Electrical Engineering at MIT; and CSAIL research scientist Piotr Mitros. Upon completing the work, students will receive an “electronic certificate of accomplishment” from MITx.

Agarwal has noticed how much student cooperation is taking place in 6.002x. “What is amazing is the amount of help students are giving each other,” he says. The MITx system includes “karma points” awarded to students who are especially active in helping their peers.

But not just anyone can expect to thrive in 6.002x, no matter how much tutoring they receive: As the MITx website notes, students hoping to succeed in 6.002x must have taken an advanced physics course in electricity and magnetism, must know basic calculus and linear algebra, and must have experience working on differential equations. There is an optional portion of 6.002x, during the first half of the course, in which students can do remedial work in differential equations.

All told, the expected time commitment for 6.002x is about 10 hours per week. “Students are putting a lot of effort into the course,” Agarwal says. “Some are putting in 20 hours a week.”

For his part, Muñoz Coronel, who is in his eighth semester of studying electrical engineering, calls 6.002x “rigorous academic study.” And Murray Pearson, a programmer from Montreal, notes that the coursework “strongly encourages students to actively calculate and think and perform the steps, rather than passively browsing information.”

Like Ho, Pearson has a long-running interest in electronics, and says he wants to “start building some gadgets and having some real fun.” Too often in the past, Pearson says, when he started thinking about ideas for devices, “I had some familiarity with the components but the actual design procedures remained mysterious.”

The lure of 6.002x, Pearson notes, was enhanced by Agarwal’s lectures on MIT OpenCourseWare in recent years. When he found out through an online discussion board that MITx was enrolling, “I signed up immediately.”

Doubtless, the MITx experience will vary for everyone. But Ho offers that for those around the world who complete a course offered by MIT, “for each of us personally, secretly, it means a lot.”

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By web.mit.edu

This low-profile wrist sensor, designed by MIT professor Rosalind Picard and her group, has shown early evidence that it can gauge the severity of epileptic seizures as accurately as scalp-worn electroencephalograms EEGs (shown at right).
Image: M. Scott Brauer

In this week’s issue of the journal Neurology, researchers at MIT and two Boston hospitals provide early evidence that a simple, unobtrusive wrist sensor could gauge the severity of epileptic seizures as accurately as electroencephalograms (EEGs) do — but without the ungainly scalp electrodes and electrical leads. The device could make it possible to collect clinically useful data from epilepsy patients as they go about their daily lives, rather than requiring them to come to the hospital for observation. And if early results are borne out, it could even alert patients when their seizures are severe enough that they need to seek immediate medical attention.

Rosalind Picard, a professor of media arts and sciences at MIT, and her group originally designed the sensors to gauge the emotional states of children with autism, whose outward behavior can be at odds with what they’re feeling. The sensor measures the electrical conductance of the skin, an indicator of the state of the sympathetic nervous system, which controls the human fight-or-flight response.

In a study conducted at Children’s Hospital Boston, the research team — Picard, her student Ming-Zher Poh, neurologist Tobias Loddenkemper and four colleagues from MIT, Children’s Hospital and Brigham and Women’s Hospital — discovered that the higher a patient’s skin conductance during a seizure, the longer it took for the patient’s brain to resume the neural oscillations known as brain waves, which EEG measures.

At least one clinical study has shown a correlation between the duration of brain-wave suppression after seizures and the incidence of sudden unexplained death in epilepsy (SUDEP), a condition that claims thousands of lives each year in the United States alone. With SUDEP, death can occur hours after a seizure.

Currently, patients might use a range of criteria to determine whether a seizure is severe enough to warrant immediate medical attention. One of them is duration. But during the study at Children’s Hospital, Picard says, “what we found was that this severity measure had nothing to do with the length of the seizure.” Ultimately, data from wrist sensors could provide crucial information to patients deciding whether to roll over and go back to sleep or get to the emergency room.

Surprising signals

The realization that the wrist sensors might be of use in treating epilepsy was something of a fluke. “We’d been working with kids on the autism spectrum, and I didn’t realize, but a lot of them have seizures,” Picard says. In reviewing data from their autism studies, Picard and her group found that seizures were sometimes preceded by huge spikes in skin conductance. It seemed that their sensors might actually be able to predict the onset of seizures.

At the time, several MIT students were working in Picard’s lab through MIT’s Undergraduate Research Opportunities Program (UROP); one of them happened to be the daughter of Joseph Madsen, director of the Epilepsy Surgery Program at Children’s Hospital. “I decided it was time to meet my UROP’s dad,” Picard says.

In a project that would serve as the basis of Poh’s doctoral dissertation, Madsen agreed to let the MIT researchers test the sensors on patients with severe epilepsy, who were in the hospital for as much as a week of constant EEG monitoring. Poh and Picard considered several off-the-shelf sensors for the project, but “at the time, there was nothing we could buy that did what we needed,” Picard says. “Finally, we just built our own.”

“It’s a big challenge to make a device robust enough to withstand long hours of recording,” Poh says. “We were recording days or weeks in a row.” In early versions of the sensors, some fairly common gestures could produce false signals. Eliminating the sensors’ susceptibility to such sources of noise was largely a process of trial and error, Picard says.

Blending in

Additionally, Poh says, “I put a lot of thought into how to make it really comfortable and as nonintrusive as possible. So I packaged it all into typical sweatbands.” Since the patients in the study were children, “I allowed them to choose their favorite character on their wristband — for example, Superman, or Dora the Explorer, whatever they like,” Poh says. “To them, they were wearing a wristband. But there was a lot of complicated sensing going on inside the wristband.” Indeed, Picard says, the researchers actually lost five of their homemade sensors because hospital cleaning staff saw what they thought were ratty sweatbands lying around recently vacated rooms and simply threw them out.

For the study at Children’s Hospital, the sensors were housed in wristbands depicting characters selected by the patients.
Image: M. Scott Brauer

“Some of these children have many, many seizures every day, and they actually suffer as much from overreaction to these seizures as, potentially, from not reacting to something dangerous,” says Stephan Schuele, the director of the Epilepsy Center at Northwestern University’s Medical Faculty Foundation, who was not involved in the research. “So I think the result is very valuable, particularly in this population, because it doesn’t respond 20 times a day to any seizures. It only responds if you do have a very, very severe seizure. And it seems to be reliably responding to that.”

Schuele cautions that the new research “makes the assumption that we do have a neurophysiologic marker for SUDEP, which is EEG suppression,” and that assumption is “a little bit controversial.” “But overall,” he adds, “we do think that it’s probably the best marker we have so far.”

Picard is continuing to investigate the possibility that initially intrigued her — that the devices could predict seizures. In the meantime, however, her collaborators at Children’s Hospital are conducting a study that will follow up on the one reported in Neurology, and a similar study is beginning at Brigham and Women’s Hospital. Rather than sweatbands with TV and comic-book characters, however, the new studies will use sensors produced by Affectiva, a company that Picard started in order to commercialize her lab’s work.

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By web.mit.edu

Interactive proofs are a type of mathematical game, pioneered at MIT, in which one player — often called Arthur — tries to extract reliable information from an unreliable interlocutor — Merlin. In a new variation known as a rational proof, Merlin is still untrustworthy, but he’s a rational actor, in the economic sense.
Image: Howard Pyle

In 1993, MIT cryptography researchers Shafi Goldwasser and Silvio Micali shared in the first Gödel Prize for theoretical computer science for their work on interactive proofs — a type of mathematical game in which a player attempts to extract reliable information from an unreliable interlocutor.

In their groundbreaking 1985 paper on the topic, Goldwasser, Micali and the University of Toronto’s Charles Rackoff ’72, SM ’72, PhD ’74 proposed a particular kind of interactive proof, called a zero-knowledge proof, in which a player can establish that he or she knows some secret information without actually revealing it. Today, zero-knowledge proofs are used to secure transactions between financial institutions, and several startups have been founded to commercialize them.

At the Association for Computing Machinery’s Symposium on Theory of Computing in May, Micali, the Ford Professor of Engineering at MIT, and graduate student Pablo Azar will present a new type of mathematical game that they’re calling a rational proof; it varies interactive proofs by giving them an economic component. Like interactive proofs, rational proofs may have implications for cryptography, but they could also suggest new ways to structure incentives in contracts.

“What this work is about is asymmetry of information,” Micali adds. “In computer science, we think that valuable information is the output of a long computation, a computation I cannot do myself.” But economists, Micali says, model knowledge as a probability distribution that accurately describes a state of nature. “It was very clear to me that both things had to converge,” he says.

A classical interactive proof involves two players, sometimes designated Arthur and Merlin. Arthur has a complex problem he needs to solve, but his computational resources are limited; Merlin, on the other hand, has unlimited computational resources but is not trustworthy. An interactive proof is a procedure whereby Arthur asks Merlin a series of questions. At the end, even though Arthur can’t solve his problem himself, he can tell whether the solution Merlin has given him is valid.

In a rational proof, Merlin is still untrustworthy, but he’s a rational actor in the economic sense: When faced with a decision, he will always choose the option that maximizes his economic reward. “In the classical interactive proof, if you cheat, you get caught,” Azar explains. “In this model, if you cheat, you get less money.”

Complexity connection

Research on both interactive proofs and rational proofs falls under the rubric of computational-complexity theory, which classifies computational problems according to how hard they are to solve. The two best-known complexity classes are P and NP. Roughly speaking, P is a set of relatively easy problems, while NP contains some problems that, as far as anyone can tell, are very, very hard.

Problems in NP include the factoring of large numbers, the selection of an optimal route for a traveling salesman, and so-called satisfiability problems, in which one must find conditions that satisfy sets of logical restrictions. For instance, is it possible to contrive an attendance list for a party that satisfies the logical expression (Alice OR Bob AND Carol) AND (David AND Ernie AND NOT Alice)? (Yes: Bob, Carol, David and Ernie go to the party, but Alice doesn’t.) In fact, the vast majority of the hard problems in NP can be recast as satisfiability problems.

To get a sense of how rational proofs work, consider the question of how many solutions a satisfiability problem has — an even harder problem than finding a single solution. Suppose that the satisfiability problem is a more complicated version of the party-list problem, one involving 20 invitees. With 20 invitees, there are 1,048,576 possibilities for the final composition of the party. How many of those satisfy the logical expression? Arthur doesn’t have nearly enough time to test them all.

But what if Arthur instead auctions off a ticket in a lottery? He’ll write down one perfectly random list of party attendees — Alice yes, Bob no, Carol yes and so on — and if it satisfies the expression, he’ll give the ticketholder $1,048,576. How much will Merlin bid for the ticket?

Suppose that Merlin knows that there are exactly 300 solutions to the satisfiability problem. The chances that Arthur’s party list is one of them are thus 300 in 1,048,576. According to standard econometric analysis, a 300-in-1,048,576 shot at $1,048,576 is worth exactly $300. So if Merlin is a rational actor, he’ll bid $300 for the ticket. From that information, Arthur can deduce the number of solutions.

First-round knockout

The details are more complicated than that, and of course, with very few exceptions, no one in the real world wants to be on the hook for a million dollars in order to learn the answer to a math problem. But the upshot of the researchers’ paper is that with rational proofs, they can establish in one round of questioning — “What do you bid?” — what might require millions of rounds using classical interactive proofs. “Interaction, in practice, is costly,” Azar says. “It’s costly to send messages over a network. Reducing the interaction from a million rounds to one provides a significant savings in time.”

“I think it’s yet another case where we think we understand what’s a proof, and there is a twist, and we get some unexpected results,” says Moni Naor, the Judith Kleeman Professorial Chair in the Department of Computer Science and Applied Mathematics at Israel’s Weizmann Institute of Science. “We’ve seen it in the past with interactive proofs, which turned out to be pretty powerful, much more powerful than you normally think of proofs that you write down and verify as being.” With rational proofs, Naor says, “we have yet another twist, where, if you assign some game-theoretical rationality to the prover, then the proof is yet another thing that we didn’t think of in the past.”

Naor cautions that the work is “just at the beginning,” and that it’s hard to say when it will yield practical results, and what they might be. But “clearly, it’s worth looking into,” he says. “In general, the merging of the research in complexity, cryptography and game theory is a promising one.”

Micali agrees. “I think of this as a good basis for further explorations,” he says. “Right now, we’ve developed it for problems that are very, very hard. But how about problems that are very, very simple?” Rational-proof systems that describe simple interactions could have an application in crowdsourcing, a technique whereby computational tasks that are easy for humans but hard for computers are farmed out over the Internet to armies of volunteers who receive small financial rewards for each task they complete. Micali imagines that they might even be used to characterize biological systems, in which individual organisms — or even cells — can be thought of as producers and consumers.

By web.mit.edu

The Association for Computing Machinery’s Council on Women in Computing (ACM-W) today named Nancy Lynch, the NEC Professor of Software Science and Engineering at MIT and a principal investigator at MIT’s Computer Science and Artificial Intelligence Laboratory (CSAIL), as the 2012-2013 Athena Lecturer. The Athena Lecturer award celebrates women researchers who have made fundamental contributions to computer science. It includes a $10,000 honorarium provided by Google.

Lynch developed mathematical approaches to understanding the capabilities of distributed systems, which rely on multiple processors for computation and coordination. These systems include traditional wired networks, modern mobile communications, cloud computing systems, parallel computers and embedded computers in factory machinery. Her contributions include modeling and proof techniques, algorithms and impossibility results that are now in the toolbox of computer scientists who design distributed systems.

“Lynch’s work has influenced both theoreticians and practitioners,” said Mary Jane Irwin, who heads the ACM-W awards committee. “Her ability to formulate many of the core problems of the field in clear and precise ways has provided a foundation that allows computer system designers to find ways to work around the limitations she verified, and to solve problems with high probability.”

In a career spanning more than 30 years, Lynch identified the boundaries between what is possible and provably impossible to solve in distributed settings. She developed new distributed algorithms, created precise models for analyzing distributed algorithms and systems, and discovered limitations on what distributed algorithms can accomplish.

Lynch’s breakthrough research with M.J. Fischer and M.S. Paterson produced the “FLP” result. It defined as a mathematical problem the challenge of establishing agreement in asynchronous distributed systems (i.e. those with no timing assumptions) in the presence of failures. This innovation had a major impact on the design of fault-tolerant distributed data-management systems and communication systems.

Lynch’s textbook, Distributed Algorithms, is the definitive reference on the basics of the field. It introduces readers to the fundamental issues underlying the design of distributed systems, including communication, coordination, synchronization and uncertainty. It integrates the results of distributed algorithms research using a common mathematical framework.

Recent work

In collaboration with A. Shvartsman and S. Gilbert, Lynch developed the RAMBO (Reconfigurable Atomic Memory for Basic Objects) algorithm, which maintains shared memory in rapidly changing networks that cannot assure access to a central server for data storage. It was originally envisioned for military applications as a means to preserve vital information for teams of soldiers operating in hostile environments. It also has applications for first responders where a stable infrastructure is not available.

In another recent project, Lynch and her collaborators proposed a new approach to programming mobile networks used for communication and for control of robots, cars and airplanes. It employs a new algorithm that allows actual mobile nodes to emulate some stationary virtual nodes, making the programming of mobile networks much easier. This emulation algorithm replicates the state of a virtual node at nearby mobile nodes, and enables the replicas to be transferred to different mobile nodes.

Background

Lynch heads the Theory of Distributed Systems Group at CSAIL. Prior to joining MIT, she served on the faculty at Tufts University, the University of Southern California, Florida International University and the Georgia Institute of Technology. A graduate of Brooklyn College with a BS in mathematics, Lynch received a PhD in mathematics from MIT in 1972.

An ACM fellow and a member of the National Academy of Engineering, Lynch and her co-authors received the 2001 and the 2007 Dijkstra Prizes in Distributed Computing. She was the first woman to win the ACM Knuth Prize, also in 2007. She was a co-winner of the first van Wijngaarden Prize in 2006 from the National Institute for Research in Mathematics and Computer Science in The Netherlands. In 2010, she received the Emanuel R. Piore Award from the Institute for Electrical and Electronics Engineers.

The Athena Lecturer is invited to present a lecture at an ACM event. Lynch’s lecture will be delivered at the 2013 joint meeting of the Symposium on Principles of Distributed Computing (PODC) and the Symposium on Parallel Algorithms and Architectures (SPAA) sponsored by the ACM Special Interest Groups on Algorithms and Computational Theory (SIGACT) and Computer Architecture (SIGARCH). Each year, the Athena Lecturer honors a preeminent woman computer scientist. Athena is the Greek goddess of wisdom; with her knowledge and sense of purpose, she epitomizes the strength, determination, and intelligence of the “Athena Lecturers.” The 2012-2013 Athena Lecturer award will be presented at the ACM Annual Awards Banquet, June 16, in San Francisco.

By web.mit.edu

Thirteen MIT faculty members are among 220 leaders from academia, business, public affairs, the humanities and the arts elected as new members of the American Academy of Arts and Sciences, the Academy announced today.

One of the nation’s most prestigious honorary societies, the Academy is also a leading center for independent policy research. Members contribute to Academy publications and studies of science and technology policy, energy and global security, social policy and American institutions, the humanities and culture, and education.

Those elected from MIT this year are:

• Robert Guy Griffin, professor of chemistry and director of the Francis Bitter National Magnet Laboratory;
• Angela M. Belcher, the Germeshausen Professor of Materials Science and Engineering and Biological Engineering;
• Emery N. Brown, professor of computational neuroscience and of health sciences and technology at MIT, and Warren M. Zapol Professor of Anaesthesia, Harvard Medical School and Massachusetts General Hospital;
• Arvind, the Charles W. and Jennifer C. Johnson Professor of Computer Science and Engineering;
• Matthew A. Wilson, Sherman Fairchild Professor of Neuroscience and associate head for education in the Department of Brain and Cognitive Sciences;
• M. Frans Kaashoek, Charles Piper Professor in the Department of Electrical Engineering and Computer Science; associate director of the Computer Science and Artificial Intelligence Laboratory (CSAIL);
• David Autor, professor of economics;
• Bonnie Berger, professor of applied math and computer science;
• Bjorn Mikhail Poonen, Claude E. Shannon (1940) Professor in Mathematics;
• George Stephanopoulos, Arthur D. Little Professor of Chemical Engineering;
• Stephen Yablo, professor of philosophy;
• Amy Finkelstein, professor of economics; and
• Tyler E. Jacks, director of the David H. Koch Institute for Integrative Cancer Research and David H. Koch Professor of Biology.

“Election to the Academy is both an honor for extraordinary accomplishment and a call to serve,” Academy President Leslie C. Berlowitz said in a statement. “We look forward to drawing on the knowledge and expertise of these distinguished men and women to advance solutions to the pressing policy challenges of the day.”

The new class will be inducted at a ceremony on Oct. 6 at the Academy’s headquarters in Cambridge, Mass.

Since its founding in 1780, the Academy has elected leading “thinkers and doers” from each generation, including George Washington and Benjamin Franklin in the 18th century, Daniel Webster and Ralph Waldo Emerson in the 19th century, and Albert Einstein and Winston Churchill in the 20th century. The current membership includes more than 250 Nobel laureates and more than 60 Pulitzer Prize winners.
By web.mit.edu