Scale Economies and Over-Capitalization in Japanese Electric Utilities
利用1981-1985年九家日本电力公司的面板数据，估计短期均衡模型中的可变成本函数，发现多数公司短期存在规模经济但长期不经济，且七家公司因Averch-Johnson效应而过度资本化。
This paper presents empirical evidence on scale economies and overcapitalization in Japanese electric utilities. We employ the short-run equilibrium model in which the variable cost function treats capital stock as a quasi-fixed factor. We specify the variable cost function as a translog form and estimate it using panel data of nine Japanese electric utility firms during the period 1981 to 1985. Our results show that eight of the nine firms experience scale economies in the short run but diseconomies in the long run, and that seven firms significantly over-capitalize as expected by the Averch-Johnson effect.