Anchoring
Also called: anchoring bias, anchor and adjust
Anchoring is letting an initial number disproportionately shape a later judgement, even when it's irrelevant. In investing the most damaging anchor is your purchase price: it determines nothing about future value, yet it drives decisions about when to sell. Analyst target prices, 52-week highs and the previous round's valuation all work as anchors in exactly the same way.
Where this is taught
Definitions are the trailer. These free levels turn Anchoring into something you play — one bite-size lesson, with worked examples, a quiz and XP.