本研究採用二階段績效評估方法，並考量變數是否具可任意裁決之性質 (discretionary or non-discretionary factor)，評估我國地方審計機關之審計效率。在第一階段，分別應用傳統資料包絡分析法及非任意裁決性資料包絡分析法 (non-discretionary DEA)，評估 2008年至 2012年間地方審計處、室及其於 2011年組織再造前、後之績效。對於無法納入第一階段生產可 能集(production possibility set)中之外生變數(exogenous variable)，在第二階段輔以 Tobit迴歸分析法，併第一階段之結果進行分析。實證結果顯示：1.非裁決性因素對績效評估具顯著影響，若未考量非裁決性因素，將使績效評估之結果產生偏誤。 2.各審計處之技術無效率主要來自組織再造前規模無效率；各審計室之技術無效率主要來自純技術無效率。3.審計室男性員工、薦任八職等以下審計人員數高於平均值者，技術效率較佳。 4.所屬人員專業證照數較多之審計室之技術、純技術效率較佳。5.政治環境中，縣市首長與中央政府同一政黨、縣市議會中有一黨過半等因素，不影響審計效率；最大黨與執政首長屬相同黨派時，審計效率較差。6.監督政府預算規模與審計機關效率呈非線性關係：與審計處效率值呈負相關，而與審計室效率值呈正相關。

This paper aims to evaluate the audit efficiencies of Taiwan’s local audit agencies, branches of National Audit Office, by adopting a two-stage performance evaluation method which takes variables with discretionary or non-discretionary attributes into consideration, and thus to examine the impacts of governmental reorganization on audit efficiencies. For those exogenous variables not contained in the first stage production possibility set, the authors proceeded the second stage analysis by conducting the Tobit regression. The research subjects comprised five audit divisions and 16 audit offices for the period of 2008 to 2012. The resulting conclusions are summarized as follows. 1.Non-discretionary factors must be taken into account in the performance evaluation, or significant biased evaluation results will be obtained. 2.The technical inefficiency of audit divisions mainly resulted from pre-reorganization scale inefficiency, but the technical inefficiency of audit offices resulted from pure technical inefficiency. 3.The ratio of the number of male auditors to that of total auditors and the ratio of the number of lower-level staffs to that of the total staffs both are positively associated with technical efficiency. 4.The number of professional licenses which the auditors possessed imposes different influences on the efficiencies of audit divisions and those of audit offices. 5.Management changes of audit agencies, auditor transfers, one-party-dominance in local government, organizational change of audit agencies, and of the same ruling party for central and local government are all not significant related with operating efficiencies of the local auditing agencies, but their signs are as expected. 6.Budget size is nonlinearly negatively related to the operating efficiencies of audit divisions but positively to those of audit offices.