Based on simple time series plots and periodic sample autocorrelations, we document that monthly river flow data display long memory, in addition to pronounced seasonality. In fact, it appears that the long memory characteristics vary with the season. To describe these two properties jointly, we...

In electrical power systems with strong hydro generation, the use of adequate techniques to generate synthetic hydrological scenarios is extremely important for the evaluation of the ways the system behaves in order to meet the forecast energy demand. This paper proposes a new model to generate...

Given the current background of ongoing environmental and resource issues, the increased exploitation of clean and renewable energy could help to alleviate the energy crisis, as well as contributing to emissions reduction and environmental protection, and so promote future sustainable...

This paper deals with the sustainability of the US current account using fractional integration. We examine nominal and real exports and imports and their corresponding values deflated by GNP. The results show that only the variables deflated by GNP may contain unit roots, while nominal and real...

This paper deals with a multivariate long memory model for the specification of real output in the US, the UK, and Canada. We examine the orders of integration of the three time series first individually and then allow cross dependence between observations. Performing univariate analysis,...

In the present study we develop and implement a short term exchange rate forecasting methodology using dynamic confidence intervals based on GARCH processes and we analyze whether this methodology can be used to model a regime switch in the volatility of

Atheoretical regression trees (ART) are applied to detect changes in the mean of a stationary long memory time series when location and number are unknown. It is shown that the BIC, which is almost always used as a pruning method, does not operate well in the long memory framework. A new method...

In this article we want to examine the time series behaviour of the UK unemployment using new statistical tools based on long memory nonstationary processes. In particular, we use a procedure developed by Robinson (1994) that permit us to simultaneously consider unit and fractional roots at the...

In this paper we specify a multi-factor long-memory process that enables us to estimate the fractional differencing parameters at each frequency separately, and adopt this framework to model quarterly prices in three European countries (France, Italy and the UK). The empirical results suggest...

This study tests for the presence of linear and nonlinear dependences in returns and volatility for six agricultural futures daily prices series, three traded on MATIF Euronext (wheat, corn, and rapeseed), and three traded on Chicago Board of Trade (red winter wheat, corn, and soybean) over the...