The Underinvestment and Overinvestment Hypotheses: an Analysis Using Panel Data
用面板数据研究企业价值与投资的关系，发现两者呈二次曲线，存在最优投资水平，低于或高于该水平分别导致投资不足或过度问题，且最优水平与投资机会质量一致。
We study the relationship between firm value and investment to test the underinvestment and overinvestment hypotheses. The results obtained, using panel data methodology as the estimation method, indicate that the abovementioned relation is quadratic, which implies that there exists an optimal level of investment. As a consequence, firms that invest less than the optimal level suffer from an underinvestment problem, while those investing more than the optimum suffer from overinvestment. The quadratic relation is maintained when firms are classified depending on their investment opportunities, the optimum being in accordance with the quality of investment opportunities.