Decomposing promotional effects with a dynamic structural model of flexible consumption

In this article, the authors offer a methodology to decompose the effects of price promotions into brand switching, stockpiling, and change in consumption by explicitly allowing for consumer heterogeneity in brand preferences and consumption needs. They develop a dynamic structural model of a household that decides when, what, and how much to buy, as well as how much to consume, to maximize its expected utility over an infinite horizon. By making certain simplifying assumptions, the authors reduce the dimensionality of the problem. They estimate the proposed model using household purchase data in the canned tuna and paper towels categories. The results from the model offer insights into the decomposition of promotional effects into its components. This could help managers make inferences about which brand's sales are more responsive to stockpiling or increase in consumption expansion and how temporary price cuts affect future sales. Contrary to previous literature, the authors find that brand switching is not the dominant force for the increase in sales. They show that brand-loyal consumers respond to a price promotion mainly by stockpiling for future consumption, whereas brand switchers do not stockpile at all. The authors also find that heavy users stockpile more, whereas light users mainly increase consumption when there is a price promotion.