考量航空公司競爭行為之國內航線最佳運價管制策略

Abstract

自美國於1978年實施實施「開放天空」政策後，世界各國紛紛跟進，使得解除管制成為航空運輸之風潮，然而，由於我國國內航線多數屬於離島航線，且航空運輸為離島居民往返臺灣本島的唯一運具，因此，我國國內航空市場目前仍實施票價上下限管制。此票價上限管制公式係以各航空公司各航線之平均成本為運算基準核算所得，而票價下限管制為上限管制之一半，使業者可於運價管制範圍內，依據尖、離峰需求訂定彈性票價，惟目前之運價管制方法恐使經營較無效率之公司享有較高之票價上限管制，且此管制方法並無考量航空公司之經營管理與競爭行為。 為瞭解各航線之票價上下限管制對社會福利的影響，本研究以雙層賽局來討論政府管制下航空公司的競爭，上層為政府追求社會福利最大化下之票價上下限管制；下層為航空公司在運價管制、航空器容量等限制下之票價、班次競爭，以追求利潤最大化。另外，以羅吉特模式來推估各公司於不同票價、班次下之市占率。惟回顧過去以賽局理論探討競爭之文獻，多數以「航線」(僅考慮特定航線)為討論基準，即假設航空公司之航空器投資及經營成本完全由該經營航線決定。為了改善此不合理之假設，本研究建構以「航空公司」為討論基準的競爭模式，即假設航空公司在各航線之票價及班次決定係以追求公司整體利潤最大化為目標。 本研究以我國國內線航空市場為分析對象以瞭解模式之適用性。為避免模式過於複雜，研究於賽局之上層預設三個可行之票價上下限管制情境，每情境有不同之票價上下限管制範圍，並以基因演算法來推估不同情境下，票價及班次之納許均衡解。研究結果顯示票價上限管制確實可有效約束航空公司於票價之訂定，尤其對於獨占航線，可以避免航空公司任意調高票價，而票價下限對於各公司之票價影響較小。另外，就本研究所設定之三情境視之，國內航線應區分為兩套管制標準，即對於競爭航線應放寬票價之上下限管制，而對於獨占航線應採取較嚴格之票價上下限管制。透過所建構之模型與情境，可求得國內19條航線之最佳票價上下限管制。

Deregulation on air transport has become a trend all over the world since the Open Sky policy implemented by the US government in 1978. However, the domestic air transport market in Taiwan is still under ceiling and floor prices regulation since most of air routes are off-shore and the only one transport channel of off-shore residents to and from Taiwan Island. According to current pricing regulation, the ceiling price is basically determined according to the operating cost of the air route operated by each of domestic airlines and the regulated floor prices are set as the half of the regulated ceiling prices for the rooms of flexible pricing in response to peak and off-peak demands, suggesting that the less efficient airline will enjoy high regulated prices and yield management and competition behaviors of airlines are not considered. To understand the effect of regulated ceiling and floor prices for each of air routes to the total social welfare, a bi-level game-theoretical model is developed. The upper level aims to determine the optimal regulated ceiling and floor prices towards social welfare maximum; while the lower level models the completion behaviors of domestic air transport market for maximizing their own profit by optimally determining the prices and service frequencies subject to regulated ceiling and floor prices and airline capacity. Additionally, the Logit model is used to estimate the market share of airlines under various prices and service frequencies. It is worth noting that most of the previous game-theoretical models attempt to model the competition behaviors at the route-level (i.e. considering only one specific route) by assuming that aircraft investment and operation costs of airlines can be clearly attributed to each operating route among all. To overcome this unrealistic assumption, the proposed airline competition model (i.e. the lower level) assumes airlines simultaneously determine prices and service frequencies to maximize their total profit at company level in response to the various competitive environments and operating cost of each routes. A case study on Taiwan domestic air market is conducted to show the applicability of the proposed model. Due to the solving complexity of the proposed model, the upper level is first simplified by several preset feasible pricing scenarios with different ranges between ceiling and floor prices, Genetic Algorithms (GAs) is then used to solve the optimally determined prices and service frequencies based on the derived Nash-equilibrium conditions under various scenarios. The results show that ceiling price regulations are in effect, especially for the monopolistic air routes; but floor price regulations are no effect, suggesting that two sets of price regulation schemes should be proposed for monopolistic air routes (operated by only one airline) and competitive air routes (operated by more than two airlines). Based on the proposed model, the optimal ceiling and floor prices for a total of 19 air routes can be solved through a systematic design of regulated price scenarios.