Individual differences in anchoring: Traits and experience

a r t i c l e i n f o Anchoring is a well-known effect leading to bias in estimation in various decision-making contexts. Previous research examining the role of individual differences in anchoring susceptibility has found weak and unreliable results. In this study anchoring was examined in a simulated poker-like card game, among people with varying levels of academic achievement and using a wide variety of psychometric tests for both cogni-tive ability and decision style/personality factors. Overall, anchoring susceptibility was largely unrelated to demographic and cognitive measures but weakly correlated to measures of preference and aptitude for ratio-nality. Performance generally improved during the course of the card game task, suggesting that participants became less susceptible to anchoring with experience and these improvements were weakly-to-moderately related to demographic, cognitive and decision style measures. That is, while there were few significant pre-dictors of overall performance, cognitive ability measures and decision styles were related to decreases in anchoring susceptibility. Anchoring-and-adjustment 4 (Tversky & Kahneman, 1974) describes a robust effect in which the estimates people make are affected by other numbers that they have recently seen. This has been shown to be influenced by both relevant and irrelevant anchor values (Thorsteinson, Breier, Atwell, Hamilton, & Privette, 2008); by obviously wrong anchors (Quattrone et al., 1984); and to affect expert as well as naïve estimators — for example, altering a property's listing price changes the valuations of realtors as well as non-expert judges (Northcraft & Neale, 1987). Mechanisms proposed to explain the effect include: Tversky and Kahneman's (1974) original suggestion that people use the anchoring value as a starting point and adjust from there until they reach a " plausible " value which, due to uncertainty regarding which values are plausible, results in values being adjusted insufficiently away from the anchor ; and confirmatory hypothesis testing, whereby people examine the anchor as a possible true answer, thereby seeking evidence that might confirm this (see, e.g., Chapman & Johnson, 1999). Evidence supporting both mechanisms has been found under different circumstances (for a recent review, see Furnham & Boo, 2011). Anchoring is also affected by metacognitive factors, with Wegener, Petty, Detweiler-Bedell, and Jarvis (2001) demonstrating that the degree to which a person's attitudes change when exposed to an anchor is influenced by the perceived plausibility of that anchor. Findings of this nature suggest that the utility of anchors is consciously assessed and that such appraisals …