A Harrod modell strukturális stabilitása (Structural stability of the Harrod model)

In this study it is shown that the nontrivial hyperbolic fixed point of a nonlinear dynamical system, which is formulated by means of the adaptive expectations, corresponds to the unstable equilibrium of Harrod. We prove that this nonlinear dynamical (in the sense of Harrod) model is structurally stable under suitable economic conditions. In the case of structural stability, small changes of the functions (C1-perturbations of the vector field) describing the expected and the true time variation of the capital coefficients do not influence the qualitative properties of the endogenous variables, that is, although the trajectories may slightly change, their structure is the same as that of the unperturbed one, and therefore these models are suitable for long-time predictions. In this situation the critique of Lucas or Engel is not valid. There is no topological conjugacy between the perturbed and unperturbed models; the change of the growth rate between two levels may require different times for the perturbed and unperturbed models.

Trust and cooperation in buyer–seller relationships and networks. The co-evolution of structural balance and trust in iterated PD games

Our study has two aims: to elaborate theoretical frameworks and introduce social mechanisms of spontaneous co-operation in repeated buyer-seller relationships and to formulate hypotheses which can be empirically tested. The basis of our chain of ideas is the simple two-person Prisoner’s Dilemma game. On the one hand, its repeated variation can be applicable for the distinction of the analytical types of trust (iteration trust, strategy trust) in co-operations. On the other hand, it provides a chance to reveal those dyadic sympathy-antipathy relations, which make us understand the evolution of trust. Then we introduce the analysis of the more complicated (more than two-person) buyer-seller relationship. Firstly, we outline the possible role of the structural balancing mechanisms in forming trust in three-person buyer-seller relationships. Secondly, we put forward hypotheses to explain complex buyer-seller networks. In our research project we try to theoretically combine some of the simple concepts of game theory with certain ideas of the social-structural balance theory. Finally, it is followed by a short summary.

The financial stability and access to financing of SMEs in Hungary

The present study was prepared within the framework of cooperation between the Competitiveness Research Centre, operating within the Institute of Business Economics of Corvinus University of Budapest, and the National Association of Entrepreneurs, based on a commission from the latter. Th e goal of the study was to survey the self-financing capabilities and borrowing opportunities of majority Hungarian-owned small and medium-sized enterprises (SMEs), and to identify potential problems. The results of the research revealed that the high proportion of owner’s equity in the financing structure is not due to difficulties with borrowing, but because enterprises that cover their fi nancing primarily from their own resources have other financing opportunities at their disposal. Although general satisfaction with banks shows a diminishing tendency, it can still be interpreted favourably. The majority of companies have not encountered serious borrowing difficulties. With regard to the system of competitive tenders, company managers have sensed some improvement, but general satisfaction is still lacking. Although the research results suggest that the primary obstacle to growth in 2013 was not the lack of credit or external funding, it is important to emphasize that start-ups, young enterprises and micro-enterprises, which struggle the most with financing worries, were not represented in the analysed database.

"Rentier States" or the Relationship between Regime Stability and Exercising Power in Post-Soviet Central Asia

The paper intends to give an insight into the relations of the economic and political systems of the Central Asian republics using the theoretical framework of the "rentier economy" and "rentier state" approach. The main findings of the paper are that two (Kazakhstan and Turkmenistan) of the five states examined are commodity export dependent “full-scale” rentier states. The two political systems are of a stable neo-patrimonial regime character, while the Kyrgyz Republic and Tajikistan, poor in natural resources but dependent on external rents, may be described as "semi-rentier" states or "rentier economies". They are politically more instable, but have an altogether authoritarian, oligarchical “clan-based” character. Uzbekistan with its closed economy, showing tendencies of economic autarchy, is also a potentially politically unstable clan-based regime. Thus, in the Central Asian context, the rentier state or rentier economy character affects the political stability of the actual regimes rather than having a direct impact on whether power is exercised in an autocratic or democratic way.