近年來由於石油價格高漲、競爭激烈的狀況，使航空產業面臨很大的挑戰，多家航空公司紛紛宣告破產或走向合併的命運。因此針對這些問題，本研究想要找出解決的辦法，所以我們利用對數迴歸模型找出影響航空業需求的各因素並針對各因素做出討論。
除了利用對數迴歸模型之外，本文假設虛擬變數，結合各文獻中重要因子以及考慮季節性、低成本航空公司的加入，使得在進行需求預測時能夠更加準確並更能確切找出影響航空需求的要素。
本文以過去的文獻對影響航空需求量的變數進行實證模型的探討，並整合出三點假設針對美國與澳洲的航空業進行探討。第一，分別設立以下變數：人口、所得、GDP、原油價格、消費者物價指數、工業生產指數、失業率、航空票價、替代品票價(運輸物價指數)、低成本航空公司因素和季節因素對美國和澳洲航空需求量的影響。第二，檢驗航空需求對於價格的反應。第三，歸納航空需求為奢侈品、正常財或次級貨品。
實證結果顯示，所得、國民生產毛額、消費者物價指數、油價及失業率是影響航空需求的主要經濟變數；所得、國民生產毛額及消費者物價指數為影響美國航空需求的顯著變數；在景氣低迷時，所得、國民生產毛額、消費者物價指數下降和失業率上升的情況，連帶影響航空需求並促使航空需求降低。然而在澳洲，油價和失業率則是主因，油價對航空需求是有正向影響，而失業率則是負向影響。而隨著季節的變化，航空需求也會有所波動。在價格彈性上，美國和澳洲對於航空需求是具有價格彈性的，當航空票價上升時，人們對航空需求會減少。而所得彈性方面，航空需求在美國和澳洲皆為正常財，也就是當所得增加時，對於航空的需求會增加。
由此研究結果帶入台灣，在經濟情況穩定的大前提之下，台灣航空公司若能降低運作成本，再加上做季節性宣傳發展，使能讓航空業復甦。

Due to the reason of high oil price and severe competition within airline industry, some major airlines in the world have declared bankruptcy or merged with other airlines. The purpose of this research is to investigate the related factors in the demand for air travel in both the United States and Australia.
To find out the factors influencing the air travel demand, this research uses log-linear regression model to examine which factors affect the demand for air travel in both the United States and Australia. In addition to those variables, dummy variable are introduced to represent the effect caused by the low-cost carriers and seasonal variation.
The goal of this thesis is to test the following hypotheses.: First, we use the following variables, including a) Population, b) Income, c) Gross Domestic Product, d) Crude Oil Price, e) Consumer Price Index, f) Industry Production Index, g) Unemployment Rate, h) Air Fares, i) Price of Substitutes (CPI of Transportation), j) Low cost Carrier effect, and k) Seasonality to investigate whether they have an influence on air travel demand in the United States or Australia. Secondly, we examine if air travel is negatively related to air fare. Finally, we test whether air travel is a normal, luxury, or inferior good.
By applying log linear regression model to both the United States and Australia, we conclude that in the United States, with higher income, GDP, CPI and lower unemployment rate, air travel demand will increase. However, in Australia, main factors are oil price and unemployment rate. Oil price is positively related to the demand for air travel while unemployment rate is negatively related. Moreover, the research shows that seasonal fluctuation is significantly seen in the demand for air travel. In addition, as the demand law emphasizes, the price is elasticity to the demand for air travel in both United States and Australia. Finally, from the empirical result, air traveling is considered a normal good in both the United States and Australia.
Under the steadily economic situation, this study also suggests that airline should come up with method to lower cost down and introduce seasonal promotions.

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