Measuring Freedom in Games
The paper provides an analogue to Harsanyi’s impartial observer theorem for game forms. Behind the veil of ignorance, a policy maker ranks combinations of game forms and information about how players interact within the game forms. The paper presents axioms on the preferences of the policy maker that are necessary and sufficient for the policy maker’s preferences to be represented by the sum of an expected valuation and a freedom measure. The freedom measure is the mutual information between players’ strategies and the individual outcomes of the game, capturing the degree to which players control their outcomes. The measure generalizes several measures from the opportunity set based freedom literature to situations where agents interact. This allows freedom to be measured in general economic models and thus derive policy recommendations based on the freedom instead of the welfare of agents. To illustrate the measure and axioms, applications to civil liberties and optimal taxation are provided.