Inequality, Business Cycles, and Growth : A Unified Approach to Stabilization Policies

This paper studies the efficacy of discretionary stabilization policies, when household heterogeneity, business cycles and long-run growth interact. Consistent with empirical evidence, we develop a unified heterogeneous agent New Keynesian growth framework in which: (i) growth arises from innovative investment, (ii) a demand externality shapes economic activity, and (iii) household heterogeneity acts on those channels through the joint distribution of marginal propensities to consume (MPCs) and marginal propensities to invest (MPIs). First, we analytically show that an income redistribution channel from high-MPI "entrepreneurs" to high-MPC households increases technology growth if the stabilizer is sufficiently persistent. Second, while the aggregate demand externality pushes toward progressive stabilizers, the endogenous growth channel pushes toward regressive stabilizers. When policymakers do not balance among both extremes, a short- versus long-run stabilization tradeoff arises. We quantitatively investigate this tension based on temporary unemployment insurance extensions during the U.S. Great Recession. The government maximizes the short-run output multiplier at a value of 1.2 by financing the policy with progressive income taxes. This is, however, at the cost of a long-run output loss with a multiplier of -0.2. Overall, our analysis provides a rationale to finance stabilizers by issuing government debt and/or by shifting the tax incidence on middle-class households