  We study a simple model of information propagation in social networks, where
two quantities are introduced: the spread factor, which measures the average
maximal fraction of neighbors of a given node that interchange information
among each other, and the spreading time needed for the information to reach
such fraction of nodes. When the information refers to a particular node at
which both quantities are measured, the model can be taken as a model for
gossip propagation. In this context, we apply the model to real empirical
networks of social acquaintances and compare the underlying spreading dynamics
with different types of scale-free and small-world networks. We find that the
number of friendship connections strongly influences the probability of being
gossiped. Finally, we discuss how the spread factor is able to be applied to
other situations.
