  Both theoretical models and empirical findings suggest that the intensity of
communication among groups of people declines with their degree of geographical
separation. There is some evidence that rather than decaying uniformly with
distance, the intensity of communication might decline at different rates for
shorter and longer distances. Using Bayesian LASSO for model selection, we
introduce a statistical model for estimating the rate of communication decline
with geographic distance that allows for discontinuities in this rate. We apply
our method to an anonymized mobile phone communication dataset. Our results are
potentially useful in settings where understanding social and spatial mixing of
people is important, such as in cluster randomized trials design.
