中文摘要：

合作既是实验经济学关注的焦点,更是社会科学的基本问题。文章基于交流可以显著改善社会合作机制这一假设为研究出发点,以双重公共品自愿捐献为基础,通过对交流范围和频率的调整来检验交流机制效果的稳健性,并考察了交流机制的作用途径。研究发现：（1）交流机制运行的效果受条件限制。异质禀赋者之间的开放式交流可以促进合作,但同质禀赋者内部的封闭式交流则会破坏合作。（2）重复交流比一次性交流可以更好地促进社会合作。（3）没有任何一个因素可以单独解释在交流机制下合作水平的变化。文章的实验研究实际上给出了交流机制促进社会合作的前提条件——交流机制必须是开放式的,且最好是可持续的。

英文摘要：

Cooperation is not only the focus of experimental economics,but also the basic issue of social sciences.Based on the hypothesis that communication can significantly improve social cooperation mechanisms,this paper takes voluntary provision of double-level public goods as the basis,tests the stability of the effectiveness of communication mechanism by the adjustment to communication scope and frequency,and then explores the function routes of communication mechanism.It arrives at the conclusions as follows：firstly,the operation effectiveness of communication mechanism is restricted by conditions;open communication between ones with heterogeneous endowments can promote cooperation,but the internal close communication among ones with homogeneous endowments will undermine cooperation;secondly,repeated communication can better promote social cooperation than one-time communication;thirdly,there is no single factor that can explain the changes in cooperation level under the communication mechanism alone.The experimental study actually provides the premise condition of the improvement of social cooperation by communication mechanism,namely communication mechanism must be open and it is best to be sustainable.