In recent years, the government, of African Countries has assumed major responsibilities for economic reforms and growth. In attempting to describe their economies, economists (policymakers) in many African Countries have applied certain models that are by now widely known: Linear programming...

A bootstrap algorithm proposed by Psaradakis (2001) for hypothesis testing in I(1) regressions is discussed and shown to be valid only under the null hypothesis. A simple correction making the procedure valid under both the null and the alternative hypothesis is proposed.

The annual structure of the Spanish real GDP is investigated in this article by means of fractional integration techniques. The results show that the series can be specified in terms of an I(d) process with d smaller than one and thus showing long memory and mean-reverting behaviour.

We prove weak exogeneity is an not an impossibility with an ADL structure in the marginal and in the conditional. We show that joint stationarity requirements is driving such common belief

Most of the existing structural-change models presume that the impact of a change is instantaneous and occurs at the same time for all individuals. In this paper, we develop a new structural-change model to measure the lag length between the time when an economic crisis breaks out and the time...

Business surveys are an important element in the analysis of the short-term economic situation because of the timeliness and nature of the information they convey. Especially, surveys are often involved in econometric models in order to provide an early assessment of the current state of the...

This paper deals with the analysis of the German nominal GNP quarterly data (1973q1 – 1996q4) using a new approach based on seasonal fractional integration that allows us to incorporate a structural break that is endogenously determined by the model. The results show that the break occurs at...

This paper proposes new bridge equations for the short-term French GDP forecasting. This tool allows to nowcast the quarterly GDP growth in France for the current quarter, based on the monthly business surveys in the industrial and services sectors. We use an automatic model selection procedure...

This paper deals with the issue of the Permanent Income Hypothesis (PIH) and we show that consumption and income may be fractionally cointegrated. We use a semiparametric frequency domain procedure of Robinson (1995a), and the results show that the UK and the Japanese consumption and income are...

The assumption of linearity is tested using five statistical tests for the US and the Canadian unemployment rates. An AR(p) model was used to remove any linear structure from the series. Strong evidence in favour of non-linearity was found in the case of Canada. The result for the US is not so...