Research On Rumor Spreading Dynamics And Its Countermeasures

Rumor dissemination exhibits some new features, such as diversified transmittingchannels, fast propagation, multiple noise disturbances, and complicated response, underthe influence of new mass media. This dissertation mainly investigates rumor spreadingdynamics in consideration of forgetting mechanism, identification capability, psycho-logical diferences and media reports, and also studies ofcial countermeasures againstrumor spreading. The main work and innovation points are summarized as follows:1. By analyzing the impact of forgetting mechanism on rumor spreading dy-namics, this dissertation explores the interrelationships between forgetting mech-anism and rumor strength, and finds that the forgetting mechanism results in thetermination of rumor spreadingThis dissertation introduces a constraint condition between stifling rate and forget-ting rate, and develops a rumor spreading model in consideration of forgetting mech-anism on LiveJournal by employing the theory of complex networks. Also, the dis-sertation studies the population of spreaders and stiflers versus time, and the efect ofthe average degree, forgetting rate and stifling rate on rumor strength by using Runge-Kutta method. These findings suggest that the forgetting and stifling mechanisms aretwo efective factors which can terminate the process of rumor spreading, and the ru-mor spreading on social networks with a small average degree may be easily afected byforgetting mechanism.2. The dissertation studies the impact of the identification capability and psy-chological diferences of involved participants on rumor spreading, and extracts theinfluencing law of noise on rumor spreadingThe dissertation employs the white Gaussian noise, which follows a normal distribu-tion to describe the impact of psychological diferences of individuals on rumor spread-ing, introduces the mean and standard deviation of the normal distribution to depict theamplitude of the disturbances in rumor spreading rate, and proposes a rumor spreadingmodel incorporating the identification capability and psychological diferences of thetargeted audiences. The formulas of rumor influence and rumor threshold have beenobtained by using system dynamic theory. Result shows that influenced by the psycho- logical diferences, the population of spreaders with identification capability experiencesmore perturbations, the maximum population of spreaders becomes higher and the rumorspreading process gets longer. However, even a small number of spreaders can evoke theoutbreak of rumor if the noise is large enough.3. The impact of media reports on rumor spreading dynamics has been inves-tigated to present decision-making support for dealing with rumor spreadingThe dissertation analyzes the interplay between media reports and rumor spreading,formulates a rumor spreading model incorporating self-protection awareness and skep-ticism mechanism, derives the expression of rumor threshold and the criterion whichcan determine whether the periodic oscillations exist in the system, and researches theinfluence of diferent strategies on rumor strength and rumor threshold. These findingssuggest that many countermeasures can efectively prevent the dissemination of rumor,such as reducing the real contact rate between ignorants and spreaders, conducting theeducation among spreaders, improving the attention-degree of media to skeptics and cut-ting down the depletion rate of mass media.4. The interplay model among rumor spreading, the evolution of emergencyand ofcial countermeasures has been developed to present the criterion which canexamine the efectiveness and delaying efects of ofcial countermeasuresThis dissertation analyzes the interrelationships among rumor spreading, emergencydevelopment and the countermeasures of ofcial media, develops the interplay model,obtains a criterion to examine the efectiveness of ofcial countermeasures, and studiesthe influence of ofcial countermeasures on rumor spreading and the evolution of emer-gency. Simulation result indicates that ofcial strategies can positively afect the situationtemporarily if the credibility and audience rating of ofcial media satisfy the criterion.Otherwise, the strategies have delaying efects on the evolution of the emergency andmay plunge the emergency state into an upheaval state.