Spillovers in Attribute Advertising

Abstract When firms advertise a vertically differentiated product attribute, they increase the weight consumers put on that attribute. This creates a spillover effect as one firm’s advertising can increase demand for other firms that also have the attribute. I develop a market share attraction model and find that as spillover increases, firms advertise less. Profit can be increasing or decreasing in spillover depending on the particular industry environment. Spillover lends a “public good” quality to advertising and firms free-ride in equilibrium. An advertising ban has an ambiguous effect on the profits of firms with the attribute, but always increases profits of firms without the attribute.