Abstract: The dynamics of new products diffusion not only emerge partly from the interaction among heterogeneous consumers in social ecommerce, but also depend on consumers' psychology behavior. Accordingly, the psychology theory is worth being introduced to explore the evolution of new product diffusion.An agent-based simulation model is built to study the new product diffusion, based on the regret theory and evolutionary game theory, which can be used to support dynamic management for new product marketing.Firstly, an evolutionary game model is proposed to depict the interaction between consumers in social ecommerce, by extending a traditional symmetric game to a dynamic game. Then, the evolution learning rules are designed based on the regret theory, taking the historical information and neighbor characters into consideration. At last, using Anylogic 6.5.0, a multi-agent simulation system is developed, and then a series of simulation experiments are performed and analysed. Simulation results reveal that:(1) The product benefit has a positive effect on the stability of diffusion dynamics.Higher product benefit can result in more stable (volatile) in the diffusion process. (2) The new product diffusion also depends on the cost of product diffusion and the loss from adopting refuse strategy. The group will more likely have the Tit-for-Tat (retaliation) issue when the two variables are equivalent. If the diffusion cost is higher,the dominate strategy is refuse, and vice versa. (3)The communication strength of consumers in market is positively associated with the volatility of diffusion dynamics. The greater communication strength of consumers indicates more obvious volatility of diffusion, while the weaker communication strength more likely result in the stability of group behavior. This research can make some contributions to new product marketing, and provides a new framework to combine psychology theories and simulation models.

Key words: regret theory, evolutionary game, consumer behavior, multi-agent simulation, interaction