Entry and Exit in Hub-Spoke Networks

We offer an explanation for why regional carriers may not survive in hub-spoke networks. When a regional carrier and a hub operator compete in a spoke market, both will suffer losses in that market. But if the hub operator exists in the spoke market, its profits in connecting markets will fall. As long as the number of such markets is large enough, it is a dominant strategy for the hub operator not to exit from the spoke market. The regional carrier is then forced to exit, assuming fixed costs are not sunk.