Hyman, Max J. & Ian Savage (2021). The Value of Space During a Pandemic . Economics Letters 207, article 110039.
[Journal Website]  [Manuscript Version]

To encourage social distancing during the COVID-19 pandemic, Delta Air Lines did not sell the middle seat on its flights that had them. In the second half of 2020 its principal rivals, American Airlines and United Airlines, continued to sell the middle seat. Analysis of U.S. Department of Transportation airline ticket data on 1,358 domestic routes finds that Delta raised its fares by 15%. Therefore, passengers paid $23 to prevent a stranger from sitting next to them.

Hyman, Max J. & Ian Savage (2022). The Effect of Vertical Product Differentiation on Fare and Market Share: Evidence from Delta Air Lines’ Middle Seat Policy. Economics of Transportation 31, article 100274.
[Journal Website]  [Manuscript Version]

Delta Air Lines engaged in vertical product differentiation during the COVID-19 pandemic. To ensure that passengers did not sit next to a stranger, Delta did not sell the middle seat on its flights that had them. Its principal rivals, American Airlines and United Airlines, sold all seats. Analysis of the non-stop routes on which Delta faced head-to-head competition with American or United reveals that Delta was able to charge a 10% fare premium and increase its relative market share by 4.7 percentage points from its middle seat policy.