1 Motivation Recent changes in U.S. trade policy have sparked debates about their effect on American prosperity, national security, and federal income. This work began as an attempt to formalize the relationship between trade policy and prosperity and continues as a journey learning data science and how to apply modeling to public policy. For my first installment, I recount my experience building a Bayesian neural net to solve the problem of selecting a trade policy that optimizes American prosperity. 2 Defining The Problem Let’s begin by defining the problem we wish to solve. Problem definitions require identifying three things: Given information. This is the data we start with before any computation. For our modeling problem, we will need at a minimum data relevant to the prosperity of a nation along with trade policy data. Unknown. The unknown is the set of values you want to identify. For a modeling problem, the unknown are The templated function we wish to...