Attraction effect in crowded decision spaces : exploring the impact of decoys in choices among numerous options

Human choices are context-dependent, and options evaluation is biased by the quality and quantity of available alternatives. In the attraction effect, dominated decoys have proven effective in shifting preferences in numerous experiments, yet its relevance in real-life choices remains disputed. Part of the problem lies in the differences between laboratory settings and realistic scenarios: in the lab, participants are tested on ternary choices; in real life, consumers face choices among many options, and interactions with other context effects are frequent. We present two experiments investigating how these factors modulate the attraction effect: we manipulate the number of decoys (study1), and the number of available options (study2). Findings suggest that: (i) the attraction effect remains significant in larger sets; (ii) two decoys are more effective than one, but (iii) adding more undermines the effect; (iv) compromise options have a dampening influence on decoys, making them ineffective at targeting the intermediate option.