基于可信任第三方的网上诚信交易机制设计

Online Trust Transactions through an Incentive Mechanism based on Trusted Third Party

面对网上交易过程中存在的买卖双方双边囚徒困境问题,设计了带有集体声誉的可信任第三方主体机制(CR&TTP),采用注册费用和惩罚欺诈等形式能够实现网上诚信交易。通过构建不完全信息动态博弈模型和重复博弈模型,研究表明:在短期交易中,诚实交易者会在第1阶段选择注册CR&TTP,买卖双方在第2阶段都会选择诚实交易,并给出了机会主义交易方在第1阶段参与注册CR&TTP的纳什均衡条件;在长期交易中,当支付罚金和欺诈损失率满足一定条件时,交易双方的子博弈完美纳什均衡是双方都选择注册CR&TTP并诚信交易;通过数值分析还显示,第三方平台的惩罚因子和交易提成设置越大都会降低欺诈交易方支付CR&TTP罚金的可能性。

Considering the buyer and seller＇s bilateral prisoner dilemma in online transactions,this paper proposes a mechanism ＂Collective Reputation and Trusted Third Party（CRTTP）＂to achieve the credible trading in online transactions by means of registration fees and cheating punishment.Using the incomplete information dynamic game model and the repeated game model,this study shows that in the short-term trading process,honest traders would choose to register for CRTTP in the first stage of the game,and both the buyers and sellers would choose to trade honestly in the second stage of the game.Moreover,Nash equilibrium condition for opportunistic traders to register for CRTTP in the first stage is also calculated.On the other hand,in the long-term trading,the subgame perfect Nash equilibrium for both the buyers and sellers is to choose to register for CRTTP and trade honestly when penalty and fraud losses meet certain conditions.Numerical analysis shows that the higher penalty and trading commission of the third party would both reduce the probability for fraudulent trading parties to pay the penalty of CRTTP.