中文摘要：

合作研发是当今社会各界共同关注的重要课题。基于AJ模型，引入内生的技术溢出决策机制，建立成本不对称且产品可替代的双寡头合作研发博弈模型，揭示了成本差异、产品可替代性及自然溢出率对研发投入和社会福利的影响。根据独立性检验得到对应的博弈均衡解，并证明研发及技术溢出决策都合作将达到帕累托最优。此外，在合作研发的框架下验证了“熊彼特假说”，从一个新的视角诠释了市场竞争与R＆D投入之间的关系。

英文摘要：

Cooperative R＆D is an important issue focused by the society. By introducing endogenous spillovers into AJ model, this paper establishes a three-stage cooperative R＆D game model of duopoly with asymmetric cost and heterogeneous products. Firstly, this paper shows the impact of cost differentiation, product substitutability and natural spillovers rate on the R＆D investment and social welfare. Secondly, we get the corresponding game equilibrium according to the stand-alone test, and prove that it can achieve Pareto optimal state if firms cooperate in beth the R＆D stage and spillovers decision stage. Finally, we verify the ＂Schumpeter Hypothesis＂ under the cooperative R＆D, and provide a new perspective for interpretation of the relationship between the market competition and R＆D investment.