Meet a Doctoral Candidate

Doctoral candidate Sarah Cen remembers the lecture that sent her down the track to an upstream question.

At a talk on ethical AI, the speaker noted a variation on the famous trolley problem, which outlines a choice between two undesirable outcomes. The scenario: a self-driving car is traveling down a narrow alley with an elderly woman walking on one side and a small child on the other, and no way to thread between both. Who should the car hit?

Then the speaker said: Is this the question we should even be asking? That’s when things clicked for Cen. A self-driving car could have avoided choosing between two bad outcomes by making a decision earlier on. The question of how to design better upstream and downstream safeguards to problems like the trolley example has informed much of Cen’s work.

Alongside Devavrat Shah, the Andrew and Erna Viterbi Professor and principal researcher at MIT’s Laboratory for Information and Decision Systems, Cen has worked on a wide range of projects that tie to her interest in the interactions between humans and computational systems, from studying options for regulating social media to looking at whether people can receive good longterm outcomes when they not only compete for resources but also don’t know what resources are best for them.

Cen plans to study how to quantify the effect of an action X on an outcome Y when it’s expensive or impossible to measure this effect. “We’re interested in how decisions or interventions affect an outcome of interest, such as how criminal justice reform affects incarceration rates or how an ad campaign might change behaviors,” she says.

Cen applies the principles of promoting inclusivity to her work in the MIT community as a past co-president of GW6. Whether in computing or in the community, a system taking steps to address bias is one that enjoys legitimacy and trust, Cen says. “These principles play crucial roles in society and, ultimately, will determine which systems endure with time.”

—Text adapted from a May 18, 2022 MIT News article