Based on the ontological and epistemological problems and solutions and on the analysis of the philosophical grounds of three main schools of economics, exposed in the previous papers, a short overview of the philosophy of the multilevel reality is done. It is shown that the hierarchy of the...

The successive versions of the GTAP databases are provided with GTAPAgg, a programme that computes values of the series of the database for any regional and sectoral aggregation. A 'self-trade' issue arises from the fact that GTAPAgg aggregates the several series concerned with international...

In this paper we use weekly milling wheat price series for nine selected EU countries to evaluate levels and components of volatility in the period from July 2004 to April 2011 and to examine how sensitive the results can be to spatial aggregation of the price data. The prices were analyzed in...

Simulation methods are used to measure the expected differentials between the Mean Square Errors of the forecasts from models based on temporally disaggregated versus aggregated data. This allows for novel comparisons including long-order ARMA models, such as those expected with weekly data,...

Poland has historically demonstrated exceptional resiliency in the face of change. This paper examines how Poland coped with huge structural realignments from the rise of Solidarity until the present, seeking to provide an objective analysis of Poland’s evolution of trade structures while it...