CAJ | 학술논문

自然垄断产业的特性决定了市场结构改革的方向只能是寡头垄断。但是，在这种市场结构下，由于厂商数目少，特别容易达成合谋。合谋有利于在位厂商，但不利于社会福利增进。这便违背自然垄断产业多元化改革实现厂商效率和社会福利水平增进的初衷。在假定自然垄断产业多元化后在位厂商合谋存在的基础上，对合谋机制、现实性及其成本进行了论证。
자연롱단산업적특성결정료시장결구개혁적방향지능시과두롱단。단시，재저충시장결구하，유우엄상수목소，특별용역체성합모。합모유리우재위엄상，단불리우사회복리증진。저편위배자연롱단산업다원화개혁실현엄상효솔화사회복이수평증진적초충。재가정자연롱단산업다원화후재위엄상합모존재적기출상，대합모궤제、현실성급기성본진행료론증。
The special attribute of natural monopoly implicates that the market structure reform must be targeted at oligopoly. However, under oligopoly where only a few firms exist, collusion will be easily sustained. Collusion benefits existing firms but is detrimental to social welfare improvement, which definitely runs against ultimate goal of diversifying natural monopoly industry to enhance firm efficiency and social welfare. Moreover, the increasing returns to scale and subadditivity of cost that characterize natural monopoly will be easily destroyed. Based on the hypothesis that collusion will be sustained in the wake of diversification reform in natural monopoly industry, this paper studies the mechanism, the possibility and the costs of collusion.