大眾運輸可及性評估與效度檢驗：考量準則與空間之相依性

Abstract

近年來，政府積極推動大眾運輸建設，以減少私有運具所造成的外部成本，達到永續運輸的目標。而大眾運輸服務需要仰賴特定的場站，在都會區內部出現了大眾運輸可及性在空間上分布不均的現象，因此需要進行大眾運輸可及性評估，協助政府辨認需要改善大眾運輸可及性的地區。然而，過去探討大眾運輸可及性評估的文獻存在研究缺口，包括：缺乏有效整合不同面向與準則的評估方法；忽略評估面向與評估準則間的相依性，以及評估地區間的空間相依性；大多數研究未針對評估結果進行效度檢驗，無法得知其是否貼近現實。 本研究以多準則決策分析的框架，在考量評估面向與評估準則間的相依性以及評估地區間的空間相依性之下，運用分析網絡程序法建立新的大眾運輸可及性評估模型，並應用於臺北市與新北市進行實例分析，評估各里行政區的大眾運輸可及性；接著利用空間迴歸模型分析大眾運輸可及性與大眾運輸使用比例之間的關係，以檢驗評估結果的效度，瞭解本研究所提的評估模型之現實性；並藉由調整評估模型內的參數進行敏感度分析，以釐清模型的信度。 研究結果顯示，基於分析網絡程序法產生之大眾運輸可及性評估結果，其空間分布支持地區之間具有空間相依性之假設。透過建立空間迴歸模型，發現大眾運輸可及性的評估結果對於大眾運輸使用比例有正向顯著影響的關係。藉由比較不同空間迴歸模型的AIC與BIC值，基於分析網絡程序法產生之大眾運輸可及性評估結果具有較好的效度。敏感度分析結果顯示評估結果具有信度。最後，本研究展示政府如何利用評估結果發展大眾運輸可及性的改善計畫，並評估改善的成效。 本研究成果在學理上彌補了過去大眾運輸可及性評估方法的缺口，考慮評估準則與空間之相依性，提出了新的評估模型，並驗證評估結果具有效度與信度；在實務上能夠協助政府更有效地辨認需要改善大眾運輸可及性的地區，以供未來訂定大眾運輸發展政策之參考。

Recently, administrations have promoted transit usage to reduce the external costs caused by private vehicles and achieve the goal of sustainable transportation. Transit services rely on specific stations or stops, and transit accessibility is spatially unevenly distributed within metropolitan areas, so there is a need to assess it to support local administrations in effectively identifying the zones that suffer from poor transit accessibility. However, existing transit accessibility assessment studies reveal the following research gaps. They failed to integrate multiple perspectives and criteria effectively, neglected interdependencies among criteria and zones, and mostly ignored the validity verification for the assessment results. This study applied the framework of multi-criteria decision-making analysis to develop a novel transit accessibility assessment model. The model used the analytic network process to deal with interdependencies among criteria and zones and was applied to the case study in the Taipei Metropolitan Area, Taiwan. Then, spatial regression models were used to verify the associations of transit accessibility with the mode share of transit use and to examine the validity of the assessment results. Finally, the sensitivity analysis was conducted to examine the reliability of the assessment model. The results suggest that the geographical clustering of transit accessibility assessment results supports the existence of interdependencies among assessment zones. The positively significant influence of transit accessibility assessment results on the mode share of transit use was examined by the spatial regression models. The transit accessibility assessment model proposed in this study is recommended to generate transit accessibility assessment results with higher validity by comparing AIC and BIC values of different spatial regression models. The sensitive analysis supports the reliability of the assessment model. Finally, this study demonstrated how the assessment model can help local administrations develop plans for zones of poor transit accessibility and evaluate the improvement. The research results contribute to the literature gaps of transit accessibility assessment methods by proposing a novel assessment model considering interdependencies among criteria and zones, and the validity of assessment results and the reliability of the assessment model are verified. The assessment model can help local administrations effectively identify the zones that suffer from poor transit accessibility and develop plans for improving transit services in the future.