公司研發多樣性對股票波動度之影響

Abstract

本文選用 1950 年至 2018 年美國公司進行公司研發多樣性對股票波動度影響之研究，過去研究認為研發投入會創造無形資本，並發現研發費用會影響公司之市場價值，影響獲利能力以及併購機會等。而研發多樣性也是公司營運的重要決策，研發開發的籌資方式也會反映在公司股價表現或是發債情形上，因此本研究希望探討公司研發多樣性對股票波動度之影響。本研究選用一個研發多樣性變數以及六個控制變數，包含資產報酬率、Tobin's q、公司規模、現金比率、槓桿比率、 研發密度，進行迴歸分析，同時也控制產業和年度的效果和加入研發多樣性變數對其中兩項控制變數的交乘項進行迴歸檢測。本研究採用普通最小平方法迴歸分析，其結果顯示當公司研發多樣性越高時，股票波動度越低，而公司規模越小及研發密度越低時，將降低此效果。

This paper selects US companies from 1950 to 2018 to study the impact of corporate innovation diversity on stock volatility. Past researches have pointed out that diversity of R&D sources affects the industrial performance, which influences a firm’s profitability. Additionally, the innovation diversity also has relevance to expected stock returns and the stock’s investability. Therefore, our research looks into how innovation diversity affects stock performance of a company. Accordingly, one innovation diversity variable and six control variables, including ROA, Tobin's q, firm size, cash ratio, leverage ratio, R&D intensity, are selected for regression analysis, and the interactions of innovation diversity variable with two of the control variables, firm size and R&D intensity, are added to perform regression testing. Using ordinary least squared regression analysis, our results show that a company’s stock volatility decreases when its innovation diversity is high. Furthermore, smaller firm and lower R&D intensity will reduce the effect of innovation diversity on stock volatility.