Identifying root causes in the difference of European 4 to 3 mergers related quantitative model findings on price, investment and quality effects

EU Digital Decade 2030 connectivity targets require from operators to provide full broadband fixed and mobile population-based coverage. There is a common agreement on detected investment GAP, however the resolution plans are diverging. In order to stimulate investments, operators argue for more cooperation (horizontal mergers) among operators to improve economies of scale, while regulators advocate for more competition to force investment race. The aim of the paper to focus on how economies of scale can be improved by a horizontal merger and what size of the risk may occur from constrained competition that partially may offset efficiency benefits at total social welfare level. The research question is set to understand and identify root causes in the differences of consumer price, operator investment and service quality assessments related 4 to 3 (mobile) mergers in the EU. The methodology of the paper is that based on qualitative research on competition policy aspects initiates snowballing approach for systematic literature review and critical assessment of academic papers applying quantitative researches on Europe-wide and decades-long database for regression and DiD (Difference in Differences Model) Fixed panel model analysis. The hypothesis is that the differences in findings of quantitative models might be more transparent and understandable if relevant modelling assumptions and data specifications are explicitly expressed on which scenario the finding is relevant and valid. The novelty of the paper is to attempt to set-up an apple-to-apple comparison of different quantitative models, by adding validity criteria and the relevance of the sample-based finding for the whole data population.