Why you shouldn't buy Bitcoin when you're hungry

The dangers of decision making. In a new book, “Noise: A Flaw in Human Judgment,” Daniel Kahneman, Olivier Sibony and Cass Sunstein explore how noise — a statistical phenomenon — proves that our ability to make decisions is far less consistent than we think it is. Drawing on that, Jason Zweig here argues that investors need to recognise that and work to counter it.