# Network Tower Sharing Analysis in Greece: A Structure-Conduct-Performance Approach
## 1 Introduction  
Understanding the economic and business environment is crucial for comprehending market operations and business functions. This analysis involves examining the market structure, which significantly influences how businesses make decisions and operate under varying market conditions. For instance, different market structures, such as perfect competition, monopolistic competition, oligopoly, and monopoly, each present unique challenges and opportunities for businesses. Additionally, businesses must navigate external factors, including political, economic, socio-cultural, technological, legal, and environmental aspects, which collectively shape the business landscape. These factors impact strategic decision-making, operational efficiency, and, ultimately, business performance. Therefore, a thorough understanding of these elements is essential for businesses to adapt and thrive in a dynamic market environment. Previous research on Structure-Conduct-Performance (SCP) has encompassed a broad spectrum of empirical contexts within specific industries [1, 2]. Most research studies carriedout have created a connection between the theory and exploratory variables reflecting the market's structure, firms' conduct, and performance, aiming to identify how they interrelate with each other. The variables employed so far could be grouped in five conceptual pillars [3], according to an extended version of the SCP model. More precisely, the SCP model embraces basic conditions, market structure, market conduct, performance, and public policy. In detail, basic conditions reflect the impact and shape of every industry, including psychological, technological, geographical, and institutional factors like price elasticity, substitutes, demand growth rate from the demand side and raw material, technology, and product durability from the supply side. In addition, market structure is defined by the number of sellers and buyers, product differentiation, barriers to entry, cost structures, vertical integration, and diversification. Market conduct is addressed by pricing behavior, product strategy and advertising, research and innovation, plant investments, and legal tactics, among others. Performance is also included in terms of both financial and societal welfare, such as production and allocative efficiency, full employment, and profitability (return on assets, ROA, or return on equity, ROE, investments level, etc.). Finally, public policy is defined by taxes and subsidies, international trade rules, price controls, antitrust legislation, and information provision [3]. Furthermore, other variables that directly influence both structure and conduct, while in parallel they reflect exact specificities of every single industry, are the number of patents, the minimum efficient scale (MES), the Lerner index (difference between market price and marginal cost), seller concentration, and price rigidity [4; 5; 6; 7; 8; 9]. Current research applies the SCP paradigm in the tower-sharing market in Greece. The paper analyzes the pillars of the SCP paradigm, focusing on the causality and the influence of market structure and conduct on a firm's profitability. In that respect, the market structure defined by the number and size of Greek MNOs in the telecommunications market determines market conduct, which, in turn, determines their profitability. Various industry- and firm-specific factors are expected to be explored as influential factors for market performance, following not only the linear one-way relationship, but also examining potential feedback effects on the basis of a vice versa and non-linear approach. In that respect, the indirect impact of performance on structure and vice versa will be theoretically analyzed, too. The main research questions raised in the paper are:  
* Has the above-described extended version of the SCP paradigm been proven effective as a methodological tool applied in the Greek telecommunications market?