The subject of the scientific research is the integration of the theoretical fundaments and econometric modeling of the chain related conditions of competition, market share, and profitability of business entities. The spectrum of possible impacts and connections between individual elements follows the logic of the Structure–Conduct– Performance paradigm and the New Empirical Industrial Organization. While discussing the context of the reverse impact among the mentioned elements, the dissertation highlights the arguments that indicate that causality is valid in both directions. One of the main goals of the doctoral dissertation is to provide insight into the significance, determinants and consequences of the process of the market structure change, as well as to determine the validity of the selected microeconomic concepts for measuring market concentration, market power and profit maximization models in the modern market structures. In this regard, a new approach to analyzing and measuring the conditions of competition in the relevant markets has been promoted. One of the specific goals is the systematization and the improvement of the theoretical and empirical results in this field. Taking into account the development trends and economic consequences of the transformation process of the market structures, certain factors that lead or could lead to intensification, limitation, prevention or distortion of competition conditions in modern markets have been identified. The dissertation provides a possible theoretical explanation that the market share is the result of behavior and strategic positioning of economic actors. Consulting the available literature, the dissertation suggests possible development directions of the theoretical concepts. The first direction relates to the application of simulations based on calibrated economic models of competition, while the another, the alternative approach, to the econometric formulation and model estimation, which determines the quantitative relationship between the variables that define the conditions of competition, market behavior and business performance.
