Summary – Noise

Noise by Daniel Kahneman, Olivier Sibony, and Cass R. Sunstein exposes the hidden problem of "noise"—unwanted variability in human judgments that should be consistent. Drawing on compelling examples from medicine, law, hiring, and other fields, the authors show how decisions can differ widely based on irrelevant factors like time of day or a decision-maker’s mood. This inconsistency leads to costly errors that often go unnoticed.

The book explains the difference between bias (systematic errors) and noise (random variability), revealing how noise undermines accuracy in professional and everyday decisions. Through extensive research, case studies, and practical remedies, the authors offer strategies to reduce noise and improve decision quality. Building on the analytical depth of Thinking, Fast and Slow and Nudge, Noise is a call to recognize and address a pervasive, yet overlooked, source of human error.