The power of words in online auctions: how quality rhetoric and vagueness in item listings influence herding bias and wordiness effects

Abstract This study investigates how listing characteristics influence purchasing decisions in online auctions. Specifically, it examines whether an item description’s length (i.e., wordiness) and herding bias affect the likelihood of a successful sale and explores the moderating effects of quality rhetoric and linguistic vagueness. We quantify these rhetorical characteristics using computer-aided text analysis on 230,270 auction descriptions. Our findings confirm that herding bias positively predicts sales probability, while an optimal listing length exists beyond which excessive verbosity diminishes sales likelihood. Quality rhetoric and vagueness negatively moderate the herding effect, which suggests that overt attempts to establish legitimacy under information asymmetry may generate skepticism. Furthermore, quality rhetoric amplifies the negative effect of excessive wordiness on sales, whereas vague terminology is positively associated with improved sales outcomes in wordier descriptions. These findings highlight the nuanced interplay between textual cues and consumer behavior in digital marketplaces, offering guidance for optimizing auction listing strategies.