报告题目：A Model of Click-farming

报告人：中国政府管制研究院 甄艺凯 博士

报告时间：2016年12月22日晚上18点

报告地点：36365线路检测中心6号楼210室

组织发起：36365线路检测中心前沿文献与经典著作读书会

主办单位：36365线路检测中心

协办单位：科研处

内容摘要：

To a certain kind of firms, their decision variables are different from traditional variables such as price and R&D. These decision variables impact profits of firms by changing consumer belief and behavior. As the internet business model is fully integrated into the economic life of the general public, a plenty of these decision variables become endogenous. Taking “click farming” as an example, this paper studies decision-making motives of “click farming”, equilibrium, and the impact on social welfare. Consider there are two types of consumers: sophisticated consumers that can differentiate the quality of products and naïve consumers that determine the quality of products by click farms. There are two firms: one produces qualified products and the other produces fake and inferior products. This paper builds a model and proves that: there does not exist a pure-strategy Nash equilibrium of “click farms”, whereas there exists a mixed-strategy Nash equilibrium with asymmetric (the high-quality firm has mass points at its lower bound) continuous distribution. On the basis of equilibrium results, we find that click farming behavior of firms push up the average price of the market. And by comparative statics, this paper analyzes the relationship between “click farms”of firms and net social surplus of products, and analyzes the difference between the costs of the high-quality firm and the costs of the low-quality firm. Finally, calculate and analyze the total social welfare under this market structure.

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