A modified Galam’s model for word-of-mouth information exchange

In this paper we analyze the stochastic model proposed by Galam in [S. Galam, Modelling rumors: The no plane Pentagon French hoax case, Physica A 320 (2003), 571–580], for information spreading in a ‘word-of-mouth’ process among agents, based on a majority rule. Using the communications rules among agents defined in the above reference, we first perform simulations of the ‘word-of-mouth’ process and compare the results with the theoretical values predicted by Galam’s model. Some dissimilarities arise in particular when a small number of agents is considered. We find motivations for these dissimilarities and suggest some enhancements by introducing a new parameter dependent model. We propose a modified Galam’s scheme which is asymptotically coincident with the original model in the above reference. Furthermore, for relatively small values of the parameter, we provide a numerical experience proving that the modified model often outperforms the original one.