The Rank Length Effect

Rank lists vary in the number of items ranked on the list (e.g., top 5 vs. top 20 movies on IMDb), that is, the rank length. Across ten studies, including both field and laboratory experiments, the authors examine the influence of rank length on evaluations, willingness to pay, and choice. They document a novel rank length effect: The same ranked items elicit more positive judgments when the rank length is longer (vs. shorter), although the differences in judgments between the ranked items are smaller. This effect is driven both by consumers' tendency to narrowly focus on the rank list and by the manner in which they map the rank list onto their mental number line. The rank length effect extends to willingness to pay, and choice. The authors explore three different kinds of choice contexts, discuss implications, and offer suggestions for future research.