中文摘要：

分析三阶段Bertrand-Stackelberg市场价格竞争与产品差异化选址策略，将之与Bertrand-Nash市场均衡进行静态比较；其次，构造一个具体的数字例子，演示随着产品差异化程度的提高，双寡头垄断市场中企业均衡利润的变动规律．在此基础上，识别经典的产品差异化定位博弈模型的各种假设条件，并在放松假设以讨论存在边际成本优势、消费者选择行为以及重复动态博弈的情形下，寡头垄断市场中的企业均衡利润和均衡价格的变化趋势及其稳定性问题．放松传统模型的假设条件有助于完整地理解和分析许多长期被孤立研究的产业竞争问题．

英文摘要：

This paper analyses the three-period Bertrand-Stackelberg market price competition and the strategy of product differentiation location, and makes a static contrast with Bertrand-Nash market equilibrium; then shows the influence of product differentiation degree in a firm＇ s profit change in equilibrium in duopoly market through a concrete example. Based on this, the paper identifies and relaxes the supposed conditions in the classic model of product differentiation location to discuss the varying trend and stability problems of profit and price in equilibrium in monopoly market where the advantage of marginal costs, the customers＇ strategic action and repeated dynamic game all exist. Relaxing the supposed conditions of traditional models is helpful to understand many industrial competition problems that have been studied separately for a long time.