Competitive Equilibria in Semi-Algebraic Economies

This paper develops a method to compute the equilibrium correspondence for exchangeeconomies with semi-algebraic preferences. Given a class of semi-algebraic exchange economiesparameterized by individual endowments and possibly other exogenous variables such as prefer-ence parameters or asset payo®s, there exists a semi-algebraic correspondence that maps param-eters to positive numbers such that for generic parameters each competitive equilibrium can beassociated with an element of the correspondence and each endogenous variable (i.e. prices andconsumptions) is a rational function of that value of the correspondence and the parameters.[...]