The pricing of airline tickets changes based on how much competition there is. When there are more airlines competing, prices don't go up as quickly as the travel date gets closer. This means that airlines can't charge as much when there are more options for travelers. Also, when there are different types of customers, airlines are more sensitive to competition. This shows that airlines can only charge higher prices if there are different types of customers to target. These findings explain why prices vary so much within the same flight and between different markets.