Overconfidence Bias

PMC - Overconfidence over the lifespan | Wikipedia - Overconfidence Effect | Scribbr - Overconfidence Bias

Overconfidence Bias is a cognitive bias where people have more confidence in their knowledge and judgments than is objectively justified. Research originated in the 1970s-1980s with contributions from Baruch Fischhoff and Paul Slovic. The bias takes three forms: overestimation (overrating actual performance), overplacement (overrating performance relative to others), and overprecision (excessive certainty in beliefs). Classic studies show that actual accuracy rates fall around 50% even when people claim 90% confidence. Scott Plous called it the most prevalent and potentially catastrophic problem in judgment and decision-making.