Airline networks: an econometric framework to analyze domestic u.s. air travel

TLDR: In this article, the authors examined the U.S. domestic airline network and found that the effects of 9/11 have affected all network classes, with the largest impact on the point-to-point variants.

Abstract: This paper examines the U.S. domestic airline network. Using an exhaustive definition of the airline network and a cross-section pooled time series dataset for 35 consecutive quarters covering 1995:Q1 to 2003:Q3, domestic scheduled air transportation was analyzed. Results suggest the existence of increased vertical disintegration of market segments following the events of September 11, 2001 (9/11). The effects of 9/11 have affected all network classes, with the largest impact on the point-to-point variants. The expansion of Southwest Airlines affected all variants of the networks positively, with a proportionately larger impact on the point-to-point over the hub and spoke variants. The results of this study are expected to help inform both operational and decisionmaking and policymaking. Results may also be useful to manufacturers in projecting the size and mix of of the aircraft fleet that are expected to be compatible with the evolving network.