Amid the controversies around the optimisation criteria and the objective functions when applying mathematical methods in economics, we proposed a method of quantifying a multi-criteria optimum, called critical distance method. The demonstration of this method is exemplified by assessing the...

The paper aims to model the underground economy using two different models: one based on the labor supply method and a generalized model for the allocation of time. The model based on the labor supply method is conceived as a simulating one in order to determine some reasonable thresholds of the...

There is a long period since the problem of public debt sustainability captures the attention of economists. However, there is no unanimity concerning an adequate unique sustainability indicator or function generally accepted. Just in this line of elaborating new models and improving...

The study concentrated on demonstrating how non-linear modelling can be useful to investigate the behavioural of dynamic economic systems. Using some adequate non-linear models could be a good way to find more refined solutions to actually unsolved problems or ambiguities in economics. Beginning...

Using some special models, this study tries to quantify the size of underground economy in Romania. The exposition plan includes: 1) Models based on direct approaches; 2) Models based on indirect approaches; 3) A generalised model for the allocation of time; 4) A model based on May’s logistic;...

In this paper we proposed a model deriving from physics laws, which are associated to the investments impact upon the economic system potential. Defining several physics fundamental dimensions and starting from a series of assumptions, we tried to find their possible economic meaning and...

The study focused on the early stage of Romania’s transition to the market economy during 1990-1992, based on statistical data available at that time. Because of the inherited structural distortions, the persistence of strong forces of inertia and the incoherence of economic and monetary...

Coming from standard economic growth theory and empirical evidences, we concentrated on the convergence process as a result of structural changes in economy. We investigate the differences among countries in EU in terms of the share in total economy of main sectors. Then, based on the spatial...

A balanced economic development is essentially based on self-financing of investment cycle. The efficient use of energy resources and raw materials could rise by increasing the renewal of fixed capital, which is meaning also a shift to a higher technological level. From this correlation is...

Empirical data show during the historical process of economic development profound structural changes in economy. One of the most important movements is from stages where the so-called tangible investments are predominant to those where intangible investments become predominant. Applying some...