Our model will involve two parameters: the balance between positive and negative reviewers p, and a controversy level α > 0. Concretely, we assume that there is a p fraction of positive evaluators and a 1−p fraction of negative evaluators. (For notational simplicity, we sometimes write q for 1−p.) The controversy level controls the distance between the means of the positive and negative populations: we assume that for some number µ, the density function f for positive evaluators is (µ + qα)-centered, and the density function g for negative evaluators is (µ − pα)-centered. Thus, the density function for the full population is h(x) = pf(x) + qg(x), and it has mean p(µ + qα) + q(µ − pα) = µ. In this way, our parametrization allows us to keep the mean and balance fixed while observing the effects as we vary the controversy level α