A Bayesian algorithm for sample selection bias correction

In this paper we present a technique to couple non-traditional data with statistics based on survey data, in order to partially correct for the bias produced by non-random sample selections. All major social media platforms represent huge samples of the general population, generated by a self-selection process. This implies that they are not representative of the larger public, and there are problems in extrapolating conclusions drawn from these samples to the whole population. We present an algorithm to integrate these massive data with ones coming from traditional sources, with the properties of being less extensive but more reliable. This integration allows to exploit the best of both worlds and reach the detail of typical "big data" sources and the representativeness of a carefully designed sample survey.