The Internet era has brought great convenience to our life and communication.Meanwhile,it also makes a bunch of rumors propagate faster and causes even more harm to human life.Therefore,it is necessary to perform effe...The Internet era has brought great convenience to our life and communication.Meanwhile,it also makes a bunch of rumors propagate faster and causes even more harm to human life.Therefore,it is necessary to perform effective control mechanisms to minimize the negative social impact from rumors.Thereout,firstly,we formulate a rumor spreading model considering psychological factors and thinking time,then,we add white noise(i.e.,stochastic interference)and two pulse control strategies which denote education mechanism and refutation mechanism into the model.Secondly,we obtain the global positive solutions and demonstrate the global exponential stability of the unique positive periodic rumor-free solution.Thirdly,we discuss the extinction and persistence of rumor.Moreover,we use Pontriagin’s minimum principle to explore the optimal impulse control.Finally,several numerical simulations are carried out to verify the effectiveness and availability of the theoretical analysis.We conclude that the pulse control strategies have a great influence on controlling rumor spreading,and different control strategies should be adopted under different transmission scenarios.展开更多
By manually collecting data on Internet-based rumors concerning COVID-19,we investigate the market reactions to the spread of such rumors and the government’s refutation of them.We find that frightening(reassuring)ru...By manually collecting data on Internet-based rumors concerning COVID-19,we investigate the market reactions to the spread of such rumors and the government’s refutation of them.We find that frightening(reassuring)rumors have a negative(positive)impact on investors.The refutation of frightening rumors triggers a positive market response,whereas the refutation of reassuring rumors does not cause a significant market reaction.Further analysis shows that there is a stock price drift when frightening rumors are refuted by governments.Our conclusions remain robust after considering endogeneity.Our findings support the notion that epidemic-related rumors affect investors’decisions,which add to literatures of the market responses of companies in the context of the COVID-19 pandemic and provide incremental evidence for the“the spiral of silence”theory.展开更多
基金partially supported by the Project for the National Natural Science Foundation of China(Grant Nos.72174121 and 71774111)the Program for Professor of Special Appointment(Eastern Scholar)at Shanghai Institutions of Higher Learning+1 种基金the Project for the Natural Science Foundation of Shanghai(Grant No.21ZR1444100)Project Soft Science Research of Shanghai(Grant No.22692112600)。
文摘The Internet era has brought great convenience to our life and communication.Meanwhile,it also makes a bunch of rumors propagate faster and causes even more harm to human life.Therefore,it is necessary to perform effective control mechanisms to minimize the negative social impact from rumors.Thereout,firstly,we formulate a rumor spreading model considering psychological factors and thinking time,then,we add white noise(i.e.,stochastic interference)and two pulse control strategies which denote education mechanism and refutation mechanism into the model.Secondly,we obtain the global positive solutions and demonstrate the global exponential stability of the unique positive periodic rumor-free solution.Thirdly,we discuss the extinction and persistence of rumor.Moreover,we use Pontriagin’s minimum principle to explore the optimal impulse control.Finally,several numerical simulations are carried out to verify the effectiveness and availability of the theoretical analysis.We conclude that the pulse control strategies have a great influence on controlling rumor spreading,and different control strategies should be adopted under different transmission scenarios.
基金funded by the National Natural Science Foundation of China(Grant No.71672208 and71902210)National Social Science Foundation(Grant No.21BGL095)+1 种基金Humanities and Social Sciences Foundation of Ministry of Education of China(No.19YJC630092)Program for Innovation Research in Central University of Finance and Economics
文摘By manually collecting data on Internet-based rumors concerning COVID-19,we investigate the market reactions to the spread of such rumors and the government’s refutation of them.We find that frightening(reassuring)rumors have a negative(positive)impact on investors.The refutation of frightening rumors triggers a positive market response,whereas the refutation of reassuring rumors does not cause a significant market reaction.Further analysis shows that there is a stock price drift when frightening rumors are refuted by governments.Our conclusions remain robust after considering endogeneity.Our findings support the notion that epidemic-related rumors affect investors’decisions,which add to literatures of the market responses of companies in the context of the COVID-19 pandemic and provide incremental evidence for the“the spiral of silence”theory.
