講座名稱：A Network Game Model of Community Formation and Risk Sharing

講座人：曹志剛 教授

講座時間：6月9日9:00

地點：騰訊會議直播（ID：932 399 873）

講座人介紹：

曹志剛，北京交通大學經(jīng)濟管理學院教授。2010年畢業(yè)于中科院數(shù)學與系統(tǒng)科學研究院并留院任助理研究員。2017年9月加盟北京交通大學經(jīng)濟管理學院，任“卓越百人計劃”教授。長期從事合作博弈、交通博弈、網(wǎng)絡(luò)博弈和算法博弈等方面的研究，在包括Operations Research、Mathematics of Operations Research、Games and Economic Behavior、Journal of Mathematical Economics、Social Choice and Welfare、International Journal of Game Theory和《中國科學：數(shù)學》在內(nèi)的期刊上發(fā)表多篇論文。相關(guān)成果獲中國信息經(jīng)濟學理論貢獻獎、系統(tǒng)科學與系統(tǒng)工程青年科技獎、中國決策科學青年科技獎、面上項目和優(yōu)青項目。兼任中國“雙法”研究會智能決策與博弈分會副理事長，中國運籌學會博弈論分會副理事長，中國雙法學會青年工作委員會副秘書長、網(wǎng)絡(luò)科學分會副秘書長，中國信息經(jīng)濟學會常務(wù)理事和中國運籌學會理事等職務(wù)。

講座內(nèi)容：

We investigate informal risk sharing using a dynamic network game model. In each round, a randomly selected agent experiences a negative shock, and the agent's friends decide whether to provide assistance. Assuming that agents have concave utility functions, we prove a version of the Folk Theorem. Our analysis shows that a pair of agents are able to help each other in all relevant rounds of a subgame perfect Nash equilibrium if and only if this connection is a part of a subgraph, in which each agent has a number of friends that is neither too low nor too high. We refer to this type of a subgraph as an inner-core. Connected inner-cores can be understood as communities. Although optimization problems related to inner-cores are generally NP-hard, we are able to perform several natural comparative statics.(joint work with Guopeng Li and Yiqing Xing)

主辦單位：經(jīng)濟與管理學院