Anchoring, activation, and the construction of values

Anchoring is a pervasive judgment bias in which decision makers are systema tically influenced by random and uninformative starting points. While ancho rs have been shown to affect a broad range of judgments including answers t o knowledge questions, monetary evaluations, and social judgments, the unde rlying causes of anchoring have been explored only recently. We suggest tha t anchors affect judgments by increasing the availability and construction of features that the anchor and target hold in common and reducing the avai lability of features of the target that differ from the anchor. We test thi s notion of anchoring as activation in five experiments that examine the ef fects of several experimental manipulations on judgments of value and belie f as well as on measures of cognitive processes. Our results indicate that prompting subjects to consider features of the item that are different from the anchor reduces anchoring, while increasing consideration of similar fe atures has no effect. The anchoring-as-activation approach provides a mecha nism for debiasing anchoring and also points to a common mechanism underlyi ng anchoring and a number of other judgment phenomena. (C) 1999 Academic Pr ess.