多工作者、多車輛家戶旅運混合需求模型之研究

過去有關小客車需求之研究已指出，家戶持有小客車之決策與工作者通勤距離、工作運具選擇間存有雙向影響關係，惟在探討多車輛、多工作者家戶於該等決策之相互影響關係時，因小客車持有數量之決策單位為家戶，工作運具選擇之決策單位則為個別工作者，致產生決策單位不一致之問題。面臨此等問題，過去之研究尚未能提供一合理方法。基於上述背景，本研究建構一混合需求模型，除探究多車輛、多工作者家戶旅運決策行為間之影響關係外，並探討家戶是否有第二位工作者選擇工作與小客車持有之內生影響關係，其中，工作者通勤距離與小客車持有之混合需求模型採聯立方程式予以構建；小客車持有與工作運具之聯合選擇模型採巢層方式予以建立；小客車持有與次要工作者是否選擇工作之影響關係則採轉換模式進行探討。建立之模型經以台灣地區之家戶資料從事實證分析，結果顯示家戶小客車持有之決策與工作者通勤距離、工作運具選擇呈雙向影響關係；惟與次要工作者是否選擇工作間之雙向影響關係並不顯著，可視為獨立。

關鍵字

小客車持有；通勤距離；工作運具；聯立方程式；轉換模式

並列摘要

Previous studies on auto ownership have demonstrated a two-way relationship between the decision of household auto ownership and worker commuting distance as well as mode choice. However, the issue of decision inconsistence can be arose in the case of multi-worker households, as the household as a whole is the decision marker for (the number of) auto ownership while individual workers are the decision makers for working mode choice. No reasonable solution to the problem mentioned above has been proposed to date. Therefore, this study developed a mixed choice model to study the complicated interrelationship among these decisions for multi-worker multi-car households. Besides, this study also analyzed the choice decision of whether doing-work of the second worker in the household as endogenous variables in the car ownership model. Consequently, a simultaneous equation model was developed to reflect the choices regarding commuting distance and auto ownership. The mode choice was modeled in the form of a nest structure, and the doing-work choices of second workers were modeled as a switching model structure. The model estimating results indicated that choices regarding auto ownership was related to the choice of commuting distance and commuting mode, but is not related to the work choices of second workers.