Anchoring, Activation, and the Construction of Values.

Anchoring is a pervasive judgment bias in which decision makers are systematically influenced by random and uninformative starting points. While anchors have been shown to affect a broad range of judgments including answers to knowledge questions, monetary evaluations, and social judgments, the underlying causes of anchoring have been explored only recently. We suggest that anchors affect judgments by increasing the availability and construction of features that the anchor and target hold in common and reducing the availability of features of the target that differ from the anchor. We test this notion of anchoring as activation in five experiments that examine the effects of several experimental manipulations on judgments of value and belief 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 features has no effect. The anchoring-as-activation approach provides a mechanism for debiasing anchoring and also points to a common mechanism underlying anchoring and a number of other judgment phenomena. Copyright 1999 Academic Press.