第一節 研究結論
本研究主要是將公司治理因素加入模型後，不但探討公司治理本身對可轉換 公司債延遲贖回的影響，亦在模型擴張後重新檢驗可轉換公司債延遲贖回的過去 相關文獻所提出之假說，故除了本研究所提出之公司治理假說外，亦同時驗證了 King and Mauer(2010)中提出之代理問題，與 Constantinides and Grundy(1987)、
Asquith and Mullins(1991)及 Asquith(1995)進行過實證的現金流量利益假說，及 Emery and Finnerty(1989)與 Jaffee and Shleifer(1990)等學者所實證過之財務危機 成本理論；除了加入公司治理因素外，用以判斷是否延遲贖回的因變數亦與過去 學者所使用之判斷方式不同，過去學者多以贖回溢酬為因變數，作為判斷可轉換 公司債是否延遲贖回的依據，而本文以兩個模型，模型一以實際贖回時點是否超 過理論最適贖回時點為判斷是否贖回，並以虛擬變數表示；模型二以實際贖回時 點與理論最適贖回時點之間實際差異天數的分組虛擬變數為因變數；然而，本研 究亦還有另一特點，採用 Asquith and Mullins(1991)實證得到的 20%合理贖回溢 酬進行補充驗證，由於此舉可排除贖回公告期間內股價波動的不確定性，更能 聚焦在所欲驗證的其他理論。
本研究所驗證的四個假說中，公司治理當中的外部董事占董事比例對於可轉 換公司債的延遲贖回有相當顯著的解釋力，代表公司治理對於可轉換公司債的延 遲贖回的確有影響；至於代理問題，本研究的兩個模型所得之結果幾乎都為顯著，
其意味著代理問題對於可轉換公司債的延遲贖回有顯著影響；財務危機成本的三 個子假說中，負債比率與現金的影響並不確定，原因可能在於已排除掉贖回前後 年度財務狀況出現問題的公司樣本，但流動比率為顯著，故財務危機成本理論在 本研究的實證結果中大致上可被驗證；在現金流量利益假說的驗證中，可得票面 利率對可轉換公司債延遲贖回確實有顯著影響，因此可說明現金流量利益假說確 實成立。
綜上所述，本研究加入公司治理變數後所進行的四個假說驗證，代理問題與 現金流量利益等兩個假說可完全被證實，而公司治理與財務危機成本理論亦可被 大致合理解釋。
第二節 研究限制
本研究在進行時，遭遇一些問題不易克服，因而可能造成結果有些許偏誤，
以下將分列說明：
一、在探討最主要的公司治理議題時，所剩下的樣本數較少，解釋能力相對來說 會降低。
二、公司治理資料取得不易，僅能納入三個公司治理變數，故無法選出最具代表 性之公司治理代理變數。
三、研究期間受限於樣本，僅能探討 1992 年至 2003 年間的狀況。
第三節 未來研究建議
本研究經過實證過程後提出以下建議，希望往後學者能將公司治理在可轉換 公司債延遲贖回議題上的解釋更加完善，分述如下：
一、本研究僅以外部董事比例、董事會規模與董事長兼任總經理等三項來解釋，
故未來可選取更多的公司治理或是描述董事會特性的變數，並以更具代表性 的公司治理代理變數加入模型，期能擴大公司治理面對可轉換公司債延遲贖 回議題的解釋。
二、擴大樣本數，並加入 2003 年後較近代的樣本期間，更能符合現況。
三、本研究已證實公司治理對可轉換公司債延遲贖回具有影響，因此未來可在加 入公司治理變數的模型下，針對其他本研究未驗證的假說重新進行實證。
四、本研究所採用的各假說之代理變數不全然與過去文獻所使用的代理變數相
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