Patricia Wenjie Cheng (born 1952) is a Chinese American psychologist. She is a leading researcher in cognitive psychology who works on human reasoning. She is best known for her psychological work on human understanding of causality. Her "power theory of the probabilistic contrast model," or power PC theory (1997) posits that people filter observations of events through a basic belief that causes have the power to generate (or prevent) their effects, thereby inferring specific cause-effect relations.