Long memory structures in economic variables

Author(s)

Guilherme de Oliveira Lima Cagliari Marques

• Document type: Doctoral Thesis
• Press: São Paulo.
• Institution: Universidade de São Paulo (USP). Faculdade de Economia, Administração e Contabilidade (FEA/SBD)
• Defense date: 2008-04-09

Examining board members

Vera Lucia Fava; Denisard Cneio de Oliveira Alves; Heron Carlos Esvael do Carmo; Chang Chiann; Silvia Regina Costa Lopes

• Advisor: Vera Lucia Fava

Abstract

The long-memory ARFIMA models proved to be more versatile in this study to the analysis of endurance in time series compare to the ARIMA models. The impulse-response functions of the fractionally integrated models indicate that this class of models more adequately gathers the data enclosed in the low frequencies of the series and thus these models are more befitted to evaluate how economic shocks are settled in the medium and long terms. Simulation studies unveiled that the unit root tests applied to long-memory processes have low power, and that the maximum likelihood estimators as well as those based on wavelet spectrum are efficient in estimating the fractional difference parameter. Empirical studies have found highly persistent components in the Brazilian series of the product, unemployment and consumption. The fractional co-integration analysis rebutted the results of the I(1)-I(0) framework, which suggest the non co-integration between the series of families\' consumption and the disposable income. The relative variability of these series was investigated through a wavelet multiresolution analysis. It was concluded that, in small scales, the variability between the series changes according to the time scale involved. The Purchasing Power Parity doctrine with Brazilian data has been revisited through the fractional co-integration analysis. (AU)