本研究探討公司使用衍生性商品投機的決定因素與對價值的影響。實證結果顯示，相對於非使用者，公司治理指標愈差的公司，會增加公司成為投機者的機率，公司規模、淨值市價比與可轉換公司債也是公司成為投機者的決定因素。不過，公司治理最差的公司，愈有可能成為混合使用者（同時以避險與投機目的使用衍生性商品），而不是投機者。以投機目的使用衍生性商品，對公司價值有負向的影響，而且使用金額愈多，對公司價值愈有負向的影響。比較特別的是，混合使用者使用衍生性商品對公司價值也有負面的影響，使用的金額愈多，對公司價值也愈有負面的影響，而且即使混合使用者的目的是用於避險，對公司價值仍有負向的影響。

The study investigates the determinants of firms' speculating activity and examines its potential impact on firms' value. The results suggest that weakly governed firms increase the chance of speculating. The determinants of firms' speculating activity are also related to firms' size, book-to-market ratio and convertible bonds. However, the most weakly governed firms are more likely to use derivatives for both hedging and speculative purposes, not just for speculation only. Firms engaging in derivatives speculation have lower corporate value. Further, the more amounts the firms use derivatives for speculation, the more negative the impact on the firms' value. It is interesting to note that firms using derivatives to both hedge and speculate also have lower firms value, even if they use derivatives to hedge.