Sarah Lim Wins Student Research Competition

Beginning web designers often struggle with turning their imagined designs into reality. They might know exactly how they want a page to look, but identifying the code responsible for achieving those stylistic effects is another story.

To help solve this issue, Northwestern Engineering junior Sarah Lim has developed a new system for generating low-barrier learning materials for web design. Called Ply, the system won first place at the Association for Computing Machinery (ACM) Computer-Human Interaction (CHI) 2017 Student Research Competition earlier this month in Denver, Colorado.

During the competition, students presented original research to a panel of judges, which included members from Facebook and Google. As the first-place winner, Lim received a cash prize and an opportunity to compete at the ACM grand finals.

“It was incredibly rewarding to received such positive feedback from respected members of the field,” said Lim, a computer science major. “Working on independent research comes with a constant sense of uncertainty. It was immensely relieving to hear that other researchers found my work interesting and valid.”

To develop Ply, Lim introduced a new technique called “visual regression pruning,” which inspects web pages of interest to find specific snippets of source code. If users want to recreate a complex search bar from the Airbnb homepage, for example, they can use Ply to find the relevant code used to build it. This saves them the time typically needed to sift through pages of complex HTML hierarchies in order to locate the specific code responsible for a page’s appearance.

“Ply simplifies code by testing whether or not removing a particular line changes the visual appearance of the webpage,” Lim said. “This technique works particularly well for novice developers, who care more about visual significance than the technical measurements used by current tools.”

Making computer science more accessible for beginners is a topic near Lim’s heart. Throughout high school and her first year in college, Lim actively avoided math and science. But after taking EECS 111, she changed her major from psychology to computer science.

“The leap of faith from humanities to computer science gave me a passion and completely changed my approach to learning and growth,” Lim said. “Struggling through the first two years of studying computer science taught me how to embrace intellectual discomfort instead of running away at the first sign of difficulty. Since then, I have been committed to helping others with similarly low self-efficacy make the same leap into the field.”

Lim is a member of the Design, Techology, and Research program, a student research program within Northwestern’s Delta Lab. Haoqi Zhang, Breed Junior Chair of Design and assistant professor of computer science at Northwestern, co-advised Lim’s project with PhD student Josh Hibschman.