Research on the spillover effects of promotion preannouncements on other selling products within and across brands

Purpose As e-commerce platforms and merchants increasingly adopt promotion preannouncements, understanding their spillover effects on other products within and across brands is crucial. This study aims to comprehensively investigate these spillover effects to optimize the use of promotion preannouncements. Design/methodology/approach The study uses quantitative analysis of real-world e-commerce data and four between-subjects experiments to examine the spillover effects of promotion preannouncements. Findings Promotion preannouncements negatively impact products within the same brand and category, while positively influencing products in different categories. Additionally, preannouncements create negative spillover effects on products within the same brand echelon. Moreover, powerful brands are more likely to harm different-echelon products compared to weak brands. Research limitations/implications The experiment has its own limitations because there will be differences between the simulated scenario and the real shopping scenario. Considering the practical factors, randomized field experiments cannot be conducted at the e-commerce platform level. Practical implications The findings provide managerial insights on brands and merchants to arrange the preannounced products and products being sold. Originality/value This study contributes to the field of preannouncements by developing new knowledge through a combination of quantitative analysis using e-commerce data and experiments, capturing the novel phenomenon of promotion preannouncement and its spillover effects. We study the preannouncement phase of promotions, thus enriching the multistage research on promotions. In addition, this paper innovatively divides the spillover effects of promotion preannouncement into four components and uses brand echelon as a categorization factor.