已經有很多的文獻探討研發支出與公司風險的影響，所以我們額外增加其他變數更深入的了解研發支出對公司風險的影響。我們透過CEO持股與研發支出的交互項以及現金持有與研發支出的交互項，研究在不同員工流動率下對公司風險的影響。結果顯示CEO持股與研發支出的交互項在員工流動率高的情況下對公司風險顯著為負影響。雖然投資人無法確實了解員工流動率高對於公司的真正影響，但持股高的CEO可以降低投資人的疑慮，這隱含CEO持股較高對於投資在有價值的研發專案的可能性在員工流動率高的情況下更大，因為CEO持股較高可以降低代理問題(Jensen & Meckling, 1976)。

There are many studies that have documented about the R&D expenditures to the firm risk, so we include other variables to further understand the impacts of R&D expenditures to the firm risk. We study that the influence of the interactions between CEO stock ownership and R&D expenditures and the interactions between Cash holding and R&D expenditures to the firm risk under the employee turnover. The result shows that the variable of interactions between the CEO stock ownership and R&D expenditures is negatively associated with the firm risk under the colossal employee turnover. Although the investors don’t know what exactly the veracious impacts of colossal employee turnover influence on the company, the CEO with higher proportion of shares will reduce the misgivings of the investors. It implies that the possibility of the CEO with higher proportion of shares which invest in valuable R&D projects under the colossal employee turnover is high because the CEO with higher proportion of shares will reduce the agency problem (Jensen & Meckling, 1976).

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