Inferiority, not similarity of the decoy to target, is what drives the transfer of attention underlying the attraction effect: Evidence from an eye-tracking study with real choices.

Recent studies reported that the attraction effect, whereby inferior decoys cause choice reversals, fails to replicate if the choice options are presented in a pictorial rather than abstract numerical form. We argue that the pictorial setting makes the similarity between decoy and target salient, whereas the abstract one emphasizes the inferiority relationship between them, crucial for the effect to occur. Thus, we used a novel experimental design in which both similarity and inferiority are equally easy to judge, their relative strength simple to manipulate, and choices incentivized rather than hypothetical. Using eye-tracking, we found that both the transfer of attention toward an undesirable target and choice reversal likelihood increase when the decoy is more strongly inferior but less similar to the target. This suggests that a key mechanism in the attraction effect is that, by virtue of its inferiority, a decoy projects a spotlight of attention toward the target, making it more attractive.