The Paradox of Information Access: On Modeling Polarization in the Age of Information

This article derives a new nonlinear stochastic model of the evolution of human beliefs that demonstrates how an increase in democratized information production and sharing, combined with consumers' confirmation bias and natural bias for outlying content, results in increased polarization. The model shows that the evolution of human beliefs can be approximated by a nonlinear diffusion-drift equation, in which systematic psychological biases contribute to drift, whereas other random influences contribute to diffusion. The nonlinear formulation predicts a growth in polarization that is attributable to increasing information production and sharing. While the core contribution is analytical, an anecdotal model parameter fitting empirical data is also presented. Specifically, we show that our model closely predicts the changing and increasingly polarized distribution of ideology of members of the US congress over the last quarter century (taken as an approximate proxy for shifts in the US population ideology), when we take the mobile-phone penetration curve as a proxy for the democratization of information access. The model suggests that escaping the polarizing forces in the age of information access may be an uphill battle.