Professor Jelani Nelson’s Departure To Leave 'Big Hole' in Computer Science Department


Jelani Nelson, an associate professor of Computer Science at the School of Engineering and Applied Sciences whose research focuses on designing algorithms to process large, high-dimensional datasets, will leave Harvard after this academic year to join the faculty of University of California, Berkeley.

Nelson, who joined the Computer Science faculty in July 2013, wrote in an email to The Crimson that his upcoming move to California was largely motivated by his wife’s “match” to an internal medicine residency program at a hospital in Oakland, Calif.

“Family is of the highest importance to me, so before her interview process began I committed to accepting a position as close as possible to where the [National Residency Matching Program] sent her,” Nelson wrote.

At Harvard, Nelson has taught several advanced Computer Science courses, including Computer Science 224: “Advanced Algorithms,” Computer Science 226: “Sketching Algorithms for Big Data,” and Computer Science 124: “Data Structures and Algorithms.”


Nelson has collaborated with other Computer Science faculty members as a researcher in Harvard’s Theory of Computation group, which aims to address the fundamental questions of computation as it relates to fields like computer science, engineering, and math.

Computer Science professor and fellow TOC group member Boaz Barak described Nelson as a “leader” in the study of algorithms and praised Nelson’s work in balancing accuracy and length when creating “short digests” of large datasets. Barak wrote in an email that while he never worked directly with Nelson on a research project, he spoke with him often and guest lectured for AddisCoder, a free summer program in Addis Ababa, Ethiopia created by Nelson to introduce high schoolers to programming and algorithms.

“He was a central figure in our Theory of Computation group, organizing our theory colloquium and leading many of our initiatives,” Barak wrote. “All of us in the Theory of [Computation] group think the world of Jelani and wish him the best, while still hoping that maybe at some point in the future he will return to Harvard.”

Computer Science Professor Harry R. Lewis ’68, who also works alongside Nelson in the TOC group, described Nelson as a “brilliant scientist and a great colleague” in an email.

“We are super sorry that he is leaving,” Lewis wrote.

Several teaching fellows for CS 124 said that beyond Nelson’s many accomplishments as an algorithmist, he is also a wonderful professor and mentor who always puts his students first.

Bill W. Zhang ’21, who is a CS 124 teaching fellow, said he appreciated Nelson’s commitment to walking students through challenges.

“Jelani really takes the time to sit down with students and ask them questions, guide them, give them the time to respond and think through the points he’s making, as long as it takes for the student to figure out what’s going on,” Zhang said.

“The fact that he’s leaving now leaves a very big hole in the department,” he added.

Kim Nguyen ’21, who invited Nelson to the Freshman Faculty Dinner and Classroom to Table last year, said Nelson’s commanding presence in the classroom belied a very relatable and quirky personality. She recalled a story Nelson shared with her in which he supposedly tried to email Queen Elizabeth to obtain visas for students taking his AddisCoder course.

“When I heard this story, I was just like, ‘First of all, who is this guy trying to guess emails to [United Nations] people? And then second of all, this guy actually cares so much about his students that he’s literally trying to write long emails just for this,’” Nguyen said.

Nelson will join UC Berkeley’s faculty as a professor in the Department of Electrical Engineering and Computer Science. He wrote that although he will miss Harvard, he is “quite excited” for the opportunities at UC Berkeley. In particular, he wrote he is looking forward to working at the Simons Institute for the Theory of Computing, which he described as “an entire 3-story building devoted to hosting semester-long research programs in theoretical computer science.”

“I’m also a huge fan of Berkeley Bowl (my #1 favorite supermarket in the world), and the many Eritrean, Ethiopian, and other great restaurants in the area,” Nelson wrote.

—Staff writer Amy L. Jia can be reached at Follow her on Twitter @AmyLJia.