Overconfidence effect — Excessive confidence in one's own answers to questions. For example, for certain types of questions, answers that people rate as "99% certain" turn out to be wrong 40% of the time.

Often we are faced with situations where our intuition misguides us. Cognitive biases are systematic patterns of deviation from norm or rationality in judgment. Many of these biases affect belief formation, business and economic decisions, and human behavior in general.