Assistant Professor Tsourakis Wins 2018 IEEE ICDM Test-of-Time Award

By Maisie GuziDecember 5th, 2018

Boston University Department of Computer Science Assistant Professor Charalampos (Babis) Tsourakis and his colleague, Professor U Kang (Seoul National University), in collaboration with Professor Christos Faloutsos (Carnegie Mellon University) have won the 2018 IEEE ICDM Test-of-Time Award for their 2009 paper PEGASUS: A Peta-Scale Graph Mining System – Implementation and Observations.

The full award text is posted below. Congratulations Babis, U, and Christos!

From left: U Kang, Charalampos (Babis) Tsourakis, and Christos Faloutsos.

From Carnegie Mellon – The Carnegie Mellon Database Group is pleased to announce that their 2009 paper PEGASUS: A Peta-Scale Graph Mining System – Implementation and Observations has won the 2018 IEEE ICDM Test-of-Time Award. The authors were CMU Ph.D. students U Kang and Charalampos Tsourakakis, in collaboration with Prof. Christos Faloutsos.

This paper on the PEGASUS project showed how to apply graph-mining algorithms on a Map-Reduce platform. The main insight was that a wide range of graph mining algorithms eventually require generalized iterated matrix-vector multiplications (GIMV), which can be efficiently implemented on Hadoop, as well as on SQL. It had already attracted the runner-up award for Best Application Paper in 2009.

The current award recognizes high-impact ICDM papers, and the award ceremony will be during the ICDM’18 Banquet on November 19th in Singapore.

Prof. U Kang is now faculty at Seoul National University, and Prof. Charalampos Tsourakakis is faculty at Boston University.

Groundbreaking collaboration among BU researchers rewarded with $1 million NSF grant

By Christopher R DevitsNovember 29th, 2018in Faculty, Recent News

From BU Today:

What If You Could Manage Information Overload?

Between news articles, tweets, Facebook memes, online videos, Reddit threads, and all the other media sources that we routinely tap into, it seems impossible these days to be informed without being overloaded or to stay connected without getting hopelessly tangled up.

But what if there were a machine or a mechanism that could take in all that information—words, pictures, posts, and videos, in dozens of different languages even—and somehow make sense of it all? Better yet, what if that machine could measure public sentiment about any given event, figure out how different media outlets are covering it, and unscramble the relationship between the two?

That’s the goal of a boundary-breaking collaboration between BU researchers Margrit Betke, a College of Arts & Sciences professor of computer science, Prakash Ishwar, a College of Engineering professor of electrical and computer engineering and systems engineering, Lei Guo, a College of Communication assistant professor of emerging media studies, and Derry Wijaya, a CAS assistant professor of computer science. In September 2018, the BU team was awarded a $1 million, four-year research grant from the National Science Foundation to advance their work.

The research itself is as much a part of this unusual story as the researchers who pulled it together while coming from diverse BU schools. More

Researchers from BU and MIT Work to Overcome Algorithmic Bias

By Maisie GuziNovember 28th, 2018

Computer Science Professors Adam Smith and Ran Canetti, alongside their CS PhD student Sarah Scheffler (GRS’21), are working with MIT PhD students Aloni Cohen, Nishanth Dikkala, and Govind Ramnarayan to figure out what, if anything, can be done to understand and minimize bias from decision-making systems that depend on computer programs.

Their work was recently accepted for publication at the upcoming 2019 Association for Computing Machinery conference on Fairness, Accountability, and Transparency, nicknamed “ACM FAT*.”

The full text of the article, featured in the BU Research magazine, can be found here. Congratulations Adam, Ran, and Sarah!

(From left) Adam Smith, Sarah Scheffler, and Ran Canetti. Photo by Jackie Ricciardi

Department Goes Green to Achieve Gold

By Maisie GuziNovember 9th, 2018

On Wednesday, November 7th, sustainability@BU officially certified the Boston University Department of Computer Science as a Green Department, earning the level of Gold. BU CS is the seventh department at Boston University to earn Green Department Certification, and the first in the College of Arts and Sciences.

The Green Office Certification Program, launched in 2011 through BU’s Sustainability Liaisons, aims to “raise awareness, educate, and provide measurable guidelines for greening the office environment.” Green Department Certification takes the program a step further, requiring all members of a department (faculty, students, and staff) to come together to ensure department-wide cooperation. To achieve this comprehensive certification, 80% of the offices in a department must be Green Office Certified and the department must enact overarching measures at its core.

Professors chat with Sustainability Director Lisa Tornatore after the announcement.

Abraham Matta, Professor and Chair of the Department of Computer Science, was excited that the Department is a University leader, honored with the gold-level certification. He praised everyone in the Department for working together to attain this achievement.

“Our Computer Science Department is very proud to become Green Certified and be the first department in CAS to achieve gold-level certification,” said Matta. “It goes to show how our faculty, staff, and students care about sustainability, and I hope we can continue to do more to reduce waste in the future.”

In her speech congratulating the Department, BU’s Sustainability Director, Lisa Tornatore, praised the department’s strong sustainability leadership and the efforts of individuals in working towards a Green Department Certification. She described sustainability in an office setting as an “80% individual effort”.

“Sustainability is not just about what the university is doing, it’s about what everybody here is doing as part of the community,” said Tornatore. “The effort on the behalf of the department is really key to showing the institution we are moving forward and what departments like [Computer Science] are doing.”

The bamboo plaque celebrating the Department’s achievement.

The Department was awarded a bamboo plaque to commemorate its achievement, which will be proudly displayed outside the main office door. The plaque includes information about the measures taken by the Department to become more sustainable. The introductory text reads, “The Department of Computer Science strives to educate and prepare our students to excel in the ever-evolving world of technology. We pride ourselves on fostering an innovative atmosphere at all levels, including becoming the first Green Department in CAS”.

CS Masters student Megan Fantes (CAS’18, GRS’20) felt proud to be part of a department that plans for the future, and drew parallels between the forward-thinking ideologies of both computer science and sustainability.

“Computer science is a lot about looking toward the future and being able to adapt to it, and sustainability is also about that,” said Fantes. “It’s good as a department to prioritize not only computer science, but also the sustainable factor of the future.”

The Department offered reusable coffee mugs at the celebration which included a zero-waste luncheon.

Christian Cole (CAS’11), Program Administrator and leader of the Department’s sustainability initiative, said he is “proud of the effort the department has made” to support sustainability.

“Having graduated from BU in 2011 with a BA in Environmental Science, sustainability has always been near to my heart, and I wanted to bring that passion and BU’s sustainability efforts together in my role in the Department of Computer Science,” said Cole. “It’s been a two-plus year project that I’m happy to see come to fruition.”

Cole reminded attendees that sustainability is an “ongoing process,” hinting at future department plans to implement better education around waste and possibly implement composting.

“If there’s one thing I learned in my education at BU, it’s that it’s easy to feel defeated when talking about sustainability and environmental issues,” said Cole. “But every little bit of effort counts towards a more sustainable future.”

From left: Program Administrator, Christian Cole (CAS’11), Department Chair, Abraham Matta, and Sustainability Director, Lisa Tornatore pose with the certification plaque.


CAS Professors Use Web Browsing Data to Predict Election Results

By Maisie GuziNovember 7th, 2018

From BU Today — As the predictions for the 2016 presidential election remind us, polling the electorate is an imperfect science. Most polls claimed that Hillary Clinton would be our next president—it seemed a foregone conclusion—and most polls were wrong, although many forecasts for the popular vote were very close—off by less than one percentage point. Election polling has always been inexact. It has also been time-consuming, expensive, and lacking the ability to measure the influence of short-lived events, like a candidate’s speech, or to read the electorate of small geographic areas.

Now, two Boston University professors believe they have found an alternative, one that is not only similarly accurate, but has the potential to be faster and less expensive, can target areas as small as towns, and can measure the people’s response to specific issues and events. The methodology, which correlates web browsing patterns with public opinion from polls, was developed by two College of Arts & Sciences faculty: Mark Crovella, a professor of computer science, and Dino Christenson, an associate professor of political science.

They worked with Giovanni Comarela from the University of Vicosa (formerly a BU PhD student under Crovella), Ramakrishnan Durairajan at the University of Oregon, and Paul Barford at the University of Wisconsin, Madison. Barford, who also works for ComScore, Inc., a kind of Nielsen ratings of the internet, negotiated an arrangement with comScore, which provided the researchers with the web browsing histories of more than 100,000 US residents over the 56-day period preceding the 2016 election.

All the data the researchers used was specifically authorized and released for this kind of research by the users who generated the data. The researchers’ analysis of that data—two terabytes worth containing 70 million websites—showed exactly when and where voters made decisions that led to the election of Donald Trump.

Political Scientist at Boston University, Dino Christensen, leans against a whiteboard in his office.

Dino Christenson plans to build a web API that could be used by academic researchers to gauge public opinion. Photo by Cydney Scott

It also suggested that contrary to popular and expert opinion, a last-minute dip in support for Hillary Clinton was not precipitated by a letter to Congress from FBI director James Comey that revealed that the FBI had found a new batch of relevant emails on Hillary Clinton’s server. Crovella and Christenson’s analysis clearly indicated that support for Clinton began to decline on October 25, 2016, three days before the letter was sent. That doesn’t mean, says Christenson, that the letter had no impact on support for the Democratic candidate. “The previous slippage could have just been a coincidence,” he says. “It may have been a small dip that would have rebounded had it not been for the letter…but the findings certainly cast doubt on the Comey letter as the first mover.”

For Crovella and Christenson, the importance of that finding is its proof that their methodology can measure the influence of single, brief events, such as a particular campaign stop, or a Supreme Court decision, or a scandalous news report—a valuable potential for candidates and pollsters.

“Let’s say a candidate flies in to a city, makes a speech, and flies out,” says Crovella. “How much of an effect does that have? A typical political poll is too coarse an instrument to measure that. A poll, even one that’s well done, takes three or four days to get a large enough response to be statistically significant. You can’t measure something that had an effect that lasted two days. That’s washed out of the measurement process.”

Similarly, says Crovella, the large numbers needed to give a traditional poll statistical significance prevent it from drilling down on small populations. “Because there are a lot of people participating in our data, we can look at political leanings of different populations on an early, localized geographical basis,” says Crovella. “We can do this in a fairly fine-grained way in space and time, because we’ve got records of their browsing behavior, their websites, on a minute-by-minute, hour-by-hour, day-by-day basis.”

Crovella and Christenson also say that their method can gauge big-picture support more accurately than current polling methods do. Their research, “Assessing Candidate Preference through Web Browsing History,” by Giovanni Comarela, Ramakrishnan Durairajan, Paul Barford, Dino Christenson, and Mark Crovella, is published in Proceedings of ACM KDD 2018, London, UK.

Ultimately, says Crovella, the polling system needs two things: “It needs the records of web browsing, and it needs some kind of initial poll to calibrate the machine-learning component to learn what it’s looking for.”

Calibration was the hard part, as well as the reason that massive computing power was brought to bear. How exactly does one translate website visits into reliable indicators of political leanings? Some websites are clearly biased toward one candidate or party, but many are not. And a visit to a particular site may not necessarily mean that the visitor shares the site’s opinion.

Step one was finding a credible way to determine “ground truth,” a term that describes criteria based on real-world evidence that is used to train a machine-learning algorithm. Crovella worked backwards, starting, somewhat ironically, with the results of traditional opinion polls.

Boston University computer scientist, Mark Crovella, leaning against a row of servers.

Mark Crovella says his methodology can quickly measure the public’s response to specific events, such as campaign rallies. Photo by Cydney Scott

“Let’s say you have a poll from September 1, and it shows that on this day 60 percent of the people in Michigan are leaning toward the Democratic party. You use that to train a machine-learning algorithm to look at all of the individuals in your data set and decide which of them must make up that 60 percent. Then you have an idea of what a Democratic voter looks like in terms of their website visits. You carry that forward, looking at subsequent visits and asking how the data set is changing. This method was not previously well-developed, and we had to find a new way to apply it to data that was as large as what we were studying.”

Crovella and Christenson point out that now that they have developed their approach with data that was donated, they are developing methods to accomplish the same ends that operate on encrypted data. This will improve user privacy, because no computer (other than the user’s own computer) will be able to see a user’s web browsing data.

Unsurprisingly, Crovella and Christenson’s initial analysis taught them a few things about their methodology, as well as the sentiments of voters. They learned, for example, which browsing habits were the best indicators of political leanings. “We found that referrals from social media are very informative,” says Crovella. “We found that if you simply type a search into a browser and click on that link, it’s not as likely to tell us something about your political leanings. But if you follow a link that was referred to you by a friend, it is likely that that’s indicative of your political leanings.”

What’s next? Crovella and Christenson plan to build a web function that will make their technology and methodology available to other social scientists and public opinion researchers. Crovella says they would like to build a system that social scientists can use to answer questions “like if someone goes to Chicago and gives a speech, how much does it move the needle and how long does it stay moved?”

“I would like to have a web API where any academic researcher could go on any day to query public opinion,” says Christenson. “One could type in their outcome of interest as well as the geographic area of the country and period of time, and in return get estimates of the related public opinion dynamics in real time. The applications are potentially quite broad. You could look at the public’s position on candidates, representatives, policy issues, even local events, like campaign stops or school board elections, assuming there is an underlying partisan or ideological dimension, and you wouldn’t have to spend tens of thousands of dollars on a poll or even have a poll in the field for the time period or region of interest.”

Perhaps because he is a longtime observer of political polls and a trained survey researcher, Christenson is sympathetic to the shortcomings of traditional polls.

“There is going to be error whenever you try to generalize,” he says. “And when there’s an electorate that’s as divided as the United States, it’s not surprising that polls would be off, especially by small margins in locales where we don’t have a great deal of data collection.” Still, he suggests, public opinion is too important to be marked by the limitations and costs of polls, at least if there is a way to improve upon them. And now there just might be.

BUCS Students Reflect on Grace Hopper 2018

By Maisie GuziOctober 31st, 2018in Recent News

By Maisie Guzi

On September 26, 2018, six Boston University Computer Science (CS) students arrived at the 2018 Grace Hopper Celebration (GHC) in Houston, TX ready for a week full of inspiring speakers, recruiting events, and female empowerment. The annual celebration, designed to bring together women and female-identifying people in computing from around the world, is the world’s largest gathering of women in technology.

GHC is a showcase of companies, technologies, and research focused on the successes of the female technology community. Countless opportunities for networking and career development, as well as 11 featured speakers, mentorship sessions, and an expo hall brimming with stories of women in technology past and present made this year’s event unforgettable.

Attendees praised the high level of support they received from BU throughout their GHC experience. PhD student Larissa Spinelli (GRS’18) was happy with the “institutional support” she received regarding “registration, accomodation, and flights”, which allowed her to focus on the celebration.

Lauren DiSalvo (CAS‘19) was excited to find a strong female presence at GHC, something she had not experienced before as a female CS student.

“When we boarded the plane to Houston the night before the conference started, the vast majority of people on our flight were college students also heading to Grace Hopper,” said DiSalvo. “There’s something pretty cool about being on a flight with all women in CS, since it’s not often the case in classes to have such a large female CS community.”

PhD student Larissa Spinelli (GRS’18) poses with “Empowered Women, Empower Women” sign.

Students enjoyed the variety and magnitude of networking opportunities at the event, and some even received job offers on site. DiSalvo was excited to find that attending GHC allowed her to streamline the recruitment process and find a potential job more efficiently.

“If I did not attend the conference, I am doubtful that the recruiting process would have moved this quickly for the companies that I interviewed with,” she said. “There is a significant stress lifted off of my shoulders now that I have a job offer, and I anticipate accepting it within the month.”

Rhonda Mak (CAS‘18) was thrilled to form a personal connection with a recruiter at the convention, as well as to expand her network. She received one job offer and has scheduled several phone interviews to follow up with recruiters she met at GHC.

“I had a really good conversation with a software engineer from Niantic Labs. She and I connected over our love of Pokemon and talked about what kind of work she does when developing for Pokemon Go”, said Mak. “We even added each other on LinkedIn and she encouraged me to ask her about anything related to Niantic or software development in general after the conference.”

Abie Award winner Dr. Debbie G. Senesky addresses the crowd.

Attendees also cited the variety of inspiring speakers and powerful women at the conference as contributors to an overall positive experience. Kathryn Quirk (CAS‘19) said she received “invaluable advice” from female computer scientists “in different stages of their careers” at GHC.

“The most important part of Grace Hopper for me was just being in such a supportive environment with so many like-minded women in STEM,” said Quirk. “Having such flexibility in choosing what talks to attend was amazing because I had the ability to tailor my experience to match my interests.”

Masters student Mengdie Zhou (GRS’18) agreed that the wide array of successful women at the conference was an inspiration. She described keynote speaker Justine Cassell, Associate Dean of Technology Strategy and Impact at Carnegie Mellon University, as “encouraging” and “meaningful for someone who is still searching for answers”.

“It’s amazing to see so [many] women are working [in] a computer related field. We seem related to some extent,” said Zhou. “It’s great to know they really enjoy their work.”

Mak said she was “floored” by the experience, describing a welcoming atmosphere of support and community throughout the weekend.

“Women from companies all over the world at all levels of of their careers were ready to support each other from day one of the event,” she said. “I was surprised from all the times I caught myself saying ‘that’s happened to me too!’ when women shared their stories of being in tech. I was met by kind and supportive women and allies at every step of the way.”

The BU table and team at GHC 2018.

All of the students in attendance agreed that GHC was a powerful event that allowed them to see the potential for women working in computing and technology around the world. Helen Zhang (CAS‘19) called the celebration a “once in a lifetime opportunity”, citing the importance of highlighting women in this field.

“The magnitude of the conference reflects how women are a true force in tech to be reckoned with, and also reminds us that there is a place for us in tech.”


Perry Donham Publishes New Book, “Introduction to Computer Science”

By Maisie GuziOctober 24th, 2018in Faculty, Recent News

We are proud to announce the publication of a new book by Computer Science Lecturer Perry Donham! Professor Donham’s book, Introduction to Computer Science, introduces students to the fundamentals of computer science by connecting the dots between applications they use every day and the underlying technologies that power them.

Professor Perry Donham

Professor Donham has worked at Boston University for 17 years; during that time his coursework has included a variety of graduate and undergraduate courses in computer science, administrative sciences, and leadership studies. In the Department of Computer Science, he teaches CS101: Introduction to Computer Science and CS411: Software Engineering.

Congratulations Professor Donham! A full description of the book is below:

Introduction to Computer Science introduces students to the fundamentals of computer science by connecting the dots between applications they use every day and the underlying technologies that power them. Throughout, students learn valuable technical skills including how to write simple JavaScript programs, format a webpage with HTML and CSS code, reduce the size of a file, and more.

Opening chapters of the text provide students with historical background, describe the numbering systems that computers operate with, and explain how computers store and convert data such as images and music. Later chapters explore the anatomy of computer hardware such as CPUs and memory, how computers communicate over networks, and the programming languages that allow us to solve problems using computation. The book concludes with chapters dedicated to security and privacy, the structure and function of operating systems, and the world of e-commerce.

Accessible in approach, Introduction to Computer Science is designed to help non-computer science majors learn how technology and computers power the world around them. The text is well suited for introductory courses in computer science.


BU Announces New Data Sciences Center

By Christopher R DevitsOctober 2nd, 2018in Recent News

Boston University’s President Robert Brown announced that the University plans to build a new 17-story building on Commonwealth Avenue that houses the new Data Sciences Center. In an effort to become one of the nation’s leading interdisciplinary research institutions, the new structure will house the Department of Computer Science, the Department of Mathematics & Statistics, and the Hariri Institute for Computing under one roof. BU expects that this new building, in conjunction with its renowned faculty and staff, will be a key driver in preparing its students for an evolving workforce that is becoming increasingly reliant on computing and data sciences.

Read the full article on BU Today

John Byers named Interim Associate Dean of the Faculty for the Mathematical & Computational Sciences

Professor John Byers

On Monday Sept. 17, BU CS Professor Stan Sclaroff, Interim Dean of the College of Arts and Sciences, informed the College community that he has selected BU CS Professor John Byers to serve as Interim Associate Dean of the Faculty for the Mathematical & Computational Sciences. Congratulations John!

The full official notification is below: More