Seeds aren't anchors.

Exposure to a few task-relevant numerical facts (seed facts) often improves subsequent numerical estimates. We performed two experiments to investigate the mechanism that produces these seeding effects. In Experiment 1, participants estimated national populations; in Experiment 2, they estimated between-city distances. In both, items were selected so that the actual value of the seed facts (SA) was, on average, below participants' initial estimates for those items (S1) and above the initial estimates for the transfer items (T1). Given this configuration, the anchoring position predicts that the postseeding transfer estimates should be greater than the preseeding transfer estimates (T2 > T1), whereas the feedback/induction position predicts the opposite (T2 < T1). In both experiments, the latter pattern of results emerged, supporting the conclusion that seeds aren't anchors.