本研究主要探討本國銀行績效衡量指標項目評估銀行整體經營績效，期待以一套具客觀性及公平性的量化工具，同時處理多項投入及多項產出的效率評估模式來衡量本國銀行之經營效率。

以本國銀行2009年表現作為研究對象，透過資料包絡分析法(data envelopment analysis, DEA)來進行研究，除了以Charnes、Cooper及Rhodes (CCR)三位學者於1978年提出之CCR模式以外，也採用Banker等人(1984)提出之BCC模式進行評估。

DEA分析結果發現，本國銀行之2009年度資料，透過CCR模式衡量總體效率的結果：在本研究32個受評單位中，有12個受評單位總體效率為1，代表以總體效率的角度來看，屬於有效率單位。

技術效率是透過BCC模式計算的結果，有16個受評單位技術效率為1，代表以技術效率的角度來看，屬於有效率單位。

規模效率＝總體效率／技術效率，以規模效率來看，有12個受評單位規模效率為1，代表以規模效率的角度評估結果，屬於有效率單位。

透過BCC模式可評估各個受評單位的規模報酬階段，共有23個固定規模報酬(CRS)單位，有7個規模報酬遞減(DRS)單位，以及2個規模報酬遞增(IRS)單位。

以總體效率、技術效率、規模效率來看，本國銀行相對有效率單位都有12家以上，比例相當高。本國銀行之中，有4家銀行雖技術效率為有效率單位，但總體效率卻屬於相對無效率，且都呈現規模報酬遞減，代表隨著投入繼續擴大，產出已無法以相同幅度提高，這4家銀行都是近年積極合併，或是本身規模就相當大的銀行，在近年各大銀行積極合併同業以求擴大規模之際，本國銀行也應同時審視規模效率及總體效率是否也等幅同步提昇。觀察近年本國銀行前往大陸設立辦事處的腳步，可看出經營者已經意識到規模報酬遞減的傾向，轉而積極準備擴展華人市場，而不再只是一味地擴大規模。

This research is to evaluate the overall efficiency, technical efficiency and scale efficiency of Taiwanese banks using Data envelopment analysis (DEA). DEA has been proven to be one objective and fair measuring model. Being able to process multiple input and output variables, DEA model is helpful to evaluate banks that require many input resources and expect multiple sources of income.
By studying year 2009 data of 32 Taiwanese banks, both DEA models of CCR and BCC were adopted in this research.
CCR model were to calculate overall efficiency of decision making units (DMU), 12 DMU appeared to be efficient in overall efficiency. In BCC model, 16 DMU were efficient in technically efficiency. Since scale efficiency is the result of overall efficiency / technical efficiency, it can also be calculated. 12 DMU were efficient in scale efficiency.
Through BCC model, the status of return to scale can be evaluated. 23 DMU were constant (Constant Return to Scale, CRS), 7 DMU were decreasing (Decreasing Return to Scale, DRS). Only 2 DMU were increasing (Increasing Return to Scale, IRS).
There were at least 12 DMU to be efficient in overall efficiency, technical efficiency and scale efficiency, which means over 37.5% of the 32 DMU were efficient. Four banks were efficient in technical efficiency, but relatively in-efficient in overall efficiency and scale efficiency. Nevertheless, these four banks were decreasing in return to scale. These four banks were known to be keen mergers or giants amongst Taiwanese banks. The result suggests them to review its growing scale before next expansion or acquisition. Perhaps, Taiwanese banks already sensed this trend, and that’s exactly why they are preparing to expand its market from Taiwan to other Mandarin-speaking market these years.

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