How Price Dispersion Changes when Upgrades are Introduced : Theory and Empirical Evidence from Airline Industry

This paper studies the effect of introducing a vertical differentiation strategy through sales of upgrades to a new type of premium product on the firm's price dispersion arising from its use of price discrimination for the base product. As a relevant application, we examine, both analytically and empirically, how a major U.S. airline's price dispersion in the coach cabin changed after it introduced the option to upgrade to a new type of premium economy seating within the coach cabin. We first provide a theoretical analysis that highlights two competing pressures that the new premium economy seating upgrades created on coach class prices. On the one hand, the airline benefits from lowering its prices because by allowing more customers to purchase in the first place, it increases the probability of selling upgrades (admission effect). On the other hand, for some customers, the value of flying with the airline increases due to the upgrade availability, therefore the airline may find it optimal to increase its prices (valuation effect). In the second part of the paper, we conduct an empirical investigation of the impact of upgrade introduction on coach class prices based on a proprietary transaction-level dataset from a major U.S. airline company. The empirical analysis tests the main predictions of our theoretical model and examines further nuances. The results show that the introduction of the premium economy seating upgrades is associated with an increase in the price dispersion and revenues in the coach class, the admission effect is stronger than the valuation effect on the low-end of the price distribution, and the opposite is true on the high-end of the price distribution. Finally, we provide the insight that the upgrade strategy can increase both firm revenue and consumer surplus and therefore create a win-win situation