Monthly time-series data based on agricultural commodities tend to present strong and particular patterns of seasonality. The presence of zero values in some of the seasons is not explained by the absence of reporting but is the result of actual features of agricultural processes. Seasonal unit...

This study examines the sustainability of trade deficit with allowance of structural breaks and seasonal adjustments as both variables have been subject to structural changes and affected by seasons. We find that, in all the cases, there is long run relationship between export and import. This...

In the recent rapid reforms made the global into a global village in nature and in terms of efficiency, transparency. The information flow in one market may affect the other markets in the world, because of its integration. In this regard, this paper explores the objective whether there is any...

This paper proposes a new testing approach for panel unit roots that is, unlike previously suggested tests, robust to nonstationarity in the volatility process of the innovations of the time series in the panel. Nonstationarity volatility arises for instance when there are structural breaks in...

This paper discusses two longstanding questions in growth econometrics which involve multiple hypothesis testing. In cross sectional GDP growth regressions many variables are simultaneously tested for significance. Similarly, when investigating pairwise convergence of output for $n$ countries,...

Using PIRLS (Progress in International Reading Literacy Study) data, we investigate which countries' schools can be be classified as significantly better or weaker than Germany's as regards the reading literacy of primary school children. The `standard' approach is to conduct separate tests for...

We address the problem of selecting the common factors that are relevant for forecasting macroeconomic variables. In economic forecasting using diffusion indexes the factors are ordered, according to their importance, in terms of relative variability, and are the same for each variable to...

This study shows that augmented Dickey-Fuller (ADF) test failed to detect covariance nonstationary series. Supportive of Ahamada (2004), this study finds that the cumulative sums of squares procedure in Inclán and Tiao (1994) is useful to complement the ADF test. As illustration, the ADF test...

The present paper puts forward a new hypothesis about the economic circuit, which is a product of Marx’s “period of production” and Keynes’s determination order between investment and savings. It leads to a new definition of profit which excludes any remaining competition between savings...