Confirmation bias is implicated in a range of phenomena - from attitude polarisation and filter bubbles, to “alternative” medicine hoaxes and fortune telling, to many forms of investor behaviour. What these all have in common is our set of human tendencies related to seeking out, focusing on, interpreting, and remembering information in a way that supports (confirms) our own values, beliefs or expectations.

But what does it mean to commit a confirmation error, specifically? And can you know when you are committing one? The line between “error” and “reasonable human functionin...