安全績效函數為預測道路事故頻率之模式，為評估路口或路段設計對交通安全影響之重要工具。過去在路口行人事故安全績效函數之發展，多以路口為分析單位，此類函數難以區別不同方向路口設計差異對行人事故頻率之影響。此外，建立行人事故安全績效函數所需之事故、曝光量以及道路環境等資料內容，亦與車輛事故安全績效函數有所不同；過去較缺乏行人事故安全績效函數相關研究，尤其缺乏本土化研究。基此，本研究以臺北市大型號誌化路口為例，蒐集民101－106年事故資料、號誌時相、道路幾何及行穿設施等資料，分別建立以路口及以路口方向為分析單位之安全績效函數，並比較兩者之事故頻率預測績效。根據零膨脹負二項模式結果發現，路口方向安全績效函數與路口安全績效函數在交叉驗證中之預測誤差相當，但相對於路口安全績效函數，路口方向安全績效函數較能直接反應道路幾何設計對行人事故之影響。本研究亦討論建立路口方向安全績效函數所需之資料項目與品質以及適用之分析方法，作為地方政府規劃建置相關資料之參考。

Safety performance functions (SPFs) are used for predicting road accident frequencies and are critical to the safety evaluation of road intersection and its design. Despite their importance, the SPFs specific for pedestrian-vehicle accident evaluation are relatively few. Moreover, most established pedestrian SPFs are intersection-based and thus difficult for examining the safety effect of pedestrian safety countermeasures, such as refuge islands, which are usually leg-based. Moreover, the traffic rules and environments in Taiwan are different from other countries; developing local pedestrian SPFs is therefore desired. The study develops both intersection- and leg-based pedestrian SPFs based on a comprehensive dataset collected from the Taipei City Government; the 2012-2017 dataset consists of data including road accidents, signal controls, road geometry, and pedestrian facilities. The analysis results of zero-inflated negative binomial models show that the intersection- and leg-based SPFs have a similar performance in cross validation. In contrast to the intersection-based SPFs, the leg-based SPFs could directly capture the impacts of pedestrian facilities and road geometry on pedestrian accidents. The study also discusses the data issues for establishing quality leg-based SPFs as a reference for the government to plan the establishment of road safety databases in the future.