Nalini Ambady

Nalini Ambady demonstrated that observers can form surprisingly meaningful social judgments from very brief exposures to expressive behavior, which she called thin slices. In her most famous study, published with Robert Rosenthal in 1992, students' ratings of professors based on just a few seconds of silent video predicted end-of-semester teaching evaluations.

In the original study, Ambady and Rosenthal used silent video clips lasting as little as two seconds, along with five-second and ten-second versions. Remarkably, the ratings from these ultra-brief clips correlated with the full end-of-course evaluations that students gave those same professors months later.

Ambady held positions at Harvard University, Tufts University, and Stanford University over the course of her career. She was a professor of psychology at Stanford at the time of her death in 2013.

Beyond thin-slice perception, Ambady studied nonverbal behavior, cultural influences on social perception, and how people form impressions across cultural boundaries. She also investigated how teacher expectations affect student achievement and how people decode emotions from facial expressions and body language.