Women in Computing Welcomes Alumna Alisa Liu

On November 15, Northwestern Computer Science and Women in Computing hosted “An Evening with Alisa Liu,” welcoming the alumna back to campus to meet with undergraduate students and share her path to graduate school.

Liu (’20) is a fourth-year PhD student in computer science at the University of Washington, advised by Yejin Choi and Noah Smith in the Allen School's Natural Language Processing group. She earned a bachelor’s degree in computer science and mathematics from Northwestern’s Weinberg College of Arts and Sciences.

Liu’s research centers around natural language processing (NLP), with a particular focus on developing algorithms for dataset creation, exploring ambiguity in language, and building decoding-time methods for text generation. She earned a 2022 National Science Foundation Graduate Research Fellowship to advance this work.

“In order for language models to be useful for end users, they need to be finetuned to follow instructions or to perform particular tasks. This requires training data for the model to learn from, and test data to evaluate whether the model has learned what it should,” Liu said. “I work on creating that kind of data, and in particular developing general algorithms for how we should create these datasets. For instance, how can we target the creation of particularly valuable examples? Can we combine the strengths of language models and human annotators to create better data?”

Liu began investigating NLP and computer audition as a third-year undergraduate student after connecting with mentors Douglas Downey, professor of computer science at Northwestern Engineering; Bryan Pardo, professor of computer science at the McCormick School of Engineering and a professor of radio, television, and film at Northwestern’s School of Communication; and Prem Seetharaman (PhD ’19), a research scientist at Adobe Research.

“I will always be grateful to Professors Doug Downey and Bryan Pardo and their students, who not only trained me as a young researcher, but showed me how incredibly fun research can be,” Liu said. “I felt that these research labs were the communities I belonged to most on campus, and that sense of belonging made me sure that research was the right path for me. Developing that early sense of belonging and confidence continues to help me today.”

The importance of building and working within a community resonated strongly with Liu, who heavily-weighed the research community, student culture, and size of the research group in her decision-making process around selecting a PhD program.

“I like when research feels like a shared mission and there are others to collaborate and commiserate with,” Liu said. “When I mentor undergraduates now, I also try to ensure that they also feel that they are supported by a larger community.”

Liu encouraged undergraduate students interested in pursuing research to be proactive about contacting faculty members and attending seminars. She initiated her collaboration with Downey via a cold email expressing interest in learning more about his research. After attending a teaching demo led by Seetharaman and making a connection after the talk, she also joined Pardo’s Interactive Audio Lab.

“Initially it was really challenging to handle how much there was to learn. For a long time in lab meetings, I wouldn’t understand a single word, and it was a little awkward to sit there in complete silence,” Liu said. “But I wanted to learn more, so I continued to attend and read our discussion papers (with great effort) beforehand. Eventually, I began to follow more of the conversation and then became an active participant. The key was just continuing to show up and put in that time, with stubborn determination.”

Liu reflected on the skills and knowledge she learned in the undergraduate program. Her favorite courses included CS 336: Design & Analysis of Algorithms with Jason Hartline, professor of computer science at Northwestern Engineering; Math 320: Real Analysis with Santiago Cañez, professor of instruction in mathematics at Weinberg; and Building Loving and Lasting Relationships: Marriage 101 with Alexandra Solomon, licensed clinical psychologist at The Family Institute at Northwestern University and a clinical assistant professor in the Department of Psychology.

“Undergrad is a special time for the breadth of knowledge that we gain. Even though I’ve forgotten lots of the content, I know all the soft knowledge is somewhere in my brain influencing how I think,” Liu said. “And I definitely know I can relearn things quickly when needed; after all, undergrad forced all of us to learn things quickly and learn lots of things at once.”