The sources and nature of long-term memory in aggregate output

This article examines the stochastic properties of aggregate macroeconomic time series from the standpoint of fractionally integrated models, focusing on the persistence of economic shocks. The authors develop a simple macroeconomic model that exhibits long-range dependence, a consequence of aggregation in the presence of real business cycles. To implement these results empirically, they employ a test for fractionally integrated time series based on the Hurst-Mandelbrot rescaled range. This test is robust to short-range dependence and is applied to quarterly and annual real GDP to determine the sources and nature of long-range dependence in the business cycle.