應用小世界網路傳播探討油電混合車的市場

Abstract

近十年來，二氧化碳的排放量以每年5.6%的成長率增加。因應日益惡化的地球環境，發展高效率且低污染排放的環保性運具，並且結合政策補助加以推廣，便成了各國政府面臨的首要課題。現行的環保車輛，包括瓦斯車、電動車、燃料電池車、酒精車、生質柴油、太陽能車、油電混合車（Hybrid Electric Vehicle，HEV）等。油電複合動力車因技術較為成熟，有較佳的價格優勢以及不需充電的方便性，成為現階段低污染車輛之主力產品。 本研究在小世界網路架構下，針對消費者所屬之網路特性進行模擬，並針對消費者之效用進行問卷調查，主要調查項目包括購車成本、燃油效率、能源成本以及車輛性能輸出，以二元羅吉特模式作為判斷消費者選擇機率之依據。在小世界網路的部份，主要調查受訪者之平均連結度與模仿率，配合其他網路相關參數包括網路規模、捷徑係數、叢聚係數與平均路徑長度等，將訊息擴散的網路架構予以構建。進而將小世界網路結合消費者之選擇機率，對油電混合車擴散的時間與數量關係進行模擬，並針對政策對產品的價格補貼，以及能源價格上漲，網路平均連結度改變，或是網路中平均模仿率變動等因素進行敏感度分析。 研究結果顯示，本研究所構建之小世界網路模型，套入實際銷售數據驗證之後，其結果與實際數字相當吻合，證明本研究所使用之模型，有其參考價值與可信度。若對產品價格的補助提高至售價的10%則油電混合車的起始接受機率將上升至4.498%。而不同群體之消費者對於產品的接受度亦有所不同，油電混合車在年所得100萬元以上之高所得族群的接受機率為18.216%，明顯高於其他族群，故油電車之銷售可在不同消費族群的劃分下對接受機率較高之族群進行重點行銷。本研究結果可供政府部門於未來推動油電混合車相關環保性政策作為參考，亦可供油電混合車廠商在產品訂價時做為參考依據。

In recent 10 years, the increasing rate of has been increased up to 5.6% each year. To improve the level of quality on air, the development of high-efficiency and low-emission environment-friendly vehicles as well as the design of the government subsidy strategies has become an urgent and important issue. The main environment-friendly vehicles include Liquefied Petroleum Gas, Electric Power, Fuel Cell, Ethanol Fuel, Bio-diesel, Solar Power and Hybrid Electric Vehicle (HEV) in the current situation. Due to the advantages of the lower price, mature technology and non-charged batteries, HEV has become the primary product of environment-friendly vehicles. This study aims to explore the change in the number of customers of HEV over time using a small-world model. The vehicle purchase costs, fuel cost per unit mileage and the throughput of vehicle are incorporated to formulate the utility functions of environment-friendly and traditional vehicles. In the small world model, we investigate the average degree of connectivity and the imitation rate using a survey data of consumers. By taking into account such variables as the size of the network, clustering coefficient, average path length and rewiring probability, we construct a social network and further investigate the diffusion pattern/behavior of information in the network. The combination of the choice probability and the small world network enable us to predict the number of customers of HEV over time, and to evaluate the effects of different levels of fuel price, selling price subsidy, imitation rate and connectivity on the number of customer. The result of the case study shows that our model can effectively fit the actual amount of sales of HEV. If the government provides 10% discount on the selling price of HEV as a subsidy, the initial choice probability of HEV will increase from 2.569 % to 4.498%. There exists the heterogeneity of the choice probability for different groups of consumers. Those consumers whose incomes are more then NT$ 1,000,000 per year have the choice probability of 18.216%, which is much higher than other groups of consumers. The results of this research may provide helpful insights for the government and HEV manufacturers to design the environmental policies and pricing strategies associated with HEV.