Análise de políticas fiscais através de modelos dinâmicos de equilíbrio geral com agentes heterogêneos

Abstract

This PhD thesis focuses primarily on the analysis of dynamic general equilibrium models with heterogeneous agents. The main objective of the first chapter is to analyze macroeconomic and welfare effects among alternatives for financing public infrastructure investments in Brazil, considering heterogeneous families in terms of labor productivity and credit access. In the model there are two agents’ types (p and q types) that attribute utility to public goods. The p-type has lower productivity and does not have access to capital, but both receive government transfers and pay taxes on consumption and labor income. The calibration data were obtained from National Accounts and PNAD. There are 11.31% of p-type agents, which generate 0.65% of total income and pay 0.66% of the tax burden. Transfer income represents 55% of work income for p-type and 16% for q-type. The results of the simulations indicate that a reduction of 15.71% in transfers from the q-type agent to infrastructure increases guarantees a public investment / GDP ratio of 3.75% in the long term, an optimal value estimated by Santana, Cavalcanti and Paes (2012), as well as significant welfare gains for both agents. Given the importance of public investment shown in Chapter 1 and the approval of Constitutional Amendment 95/2016 (EC 95), which deals with the ceiling of public spending, a more sophisticated model was developed in Chapter 2 with the possibility of including congestion of services offered to families and firms in order to analyze the redistributive and welfare impacts of fiscal policies. After the simulation of growth scenarios with productivity increases and / or EC 95 for periods of validity of 10 and 20 years we have concluded that only in the presence of exogenous increases productivity, compared to the baseline scenario of stagnation are guaranteed well- gains being for all agents especially for those with lower income and who do not have access to the credit market. However, the implementation of EC 95 while providing aggregate welfare gains greatly worsens the situation of the poorest agents. To circumvent the negative effects generated by the EC 95 on the welfare of these agents have proposed two policy alternatives PA1 and PA2. In PA1 was considered the end of the duration of the EC 95 the possibility of public investment return to its previous level to the implementation of this policy. In PA2 government investment is not affected by the freeze during the lifetime of EC 95. The PA2 results provided to reduce bottlenecks in the economy and was the only to ensure economic growth in the long term in the face of reduced welfare for the poorest segment. Finally in Chapter 3 the discussion about the differences between models with heterogeneous and representative agents was raised. The first with a micro-based approach in individual decisions as presented in Chapter 2 and the second one developed in this Chapter where by hypothesis families are representative ie the optimal decisions of these families are represented by a medium agent. However Comparing the results obtained in the simulations of the aggregate model with those presented in Chapter 2, we were observed that the representative agent model can introduce serious distortion to disregard the existing heterogeneity among agents. For example, it has been found that the EC 95 brings considerable welfare gains for families even in the face of declines in the economy’s product associated with the freezing of public spending. These results therefore seem to be conditioned by the reductionism in the cases present in this category of aggregate growth models.