Minimum Efficient Scale, Competition on the Merits, and The Special Responsibility of a Dominant Undertaking

As a leading model of law on abuse of dominance, Article 102 TFEU hosts two notoriously vague concepts: competition on the merits and the special responsibility of a dominant undertaking. The former could mislead abuse assessments into an illusion of inherent impropriety, while the latter is susceptible to expansive interpretations that undermine the pivotal role of dominance. We propose a test centred on the concept of minimum efficient scale, which has been seriously overlooked or even mischaracterized under Article 102, to complement the as-efficient-competitor rationale. This test clarifies—with respect to exclusionary conduct—competition on the merits in a purely efficiency-based way and gives content to the special responsibility concept. It is compatible with the case law and can be operationalized vis-à-vis digital platform markets to tackle practices such as self-preferencing. It shows potential in enhancing the robustness of ex post antitrust when ex ante regulation has become the more popular recourse

Frequentist Model Averaging for Global Fr\'{e}chet Regression

To consider model uncertainty in global Fr\'{e}chet regression and improve density response prediction, we propose a frequentist model averaging method. The weights are chosen by minimizing a cross-validation criterion based on Wasserstein distance. In the cases where all candidate models are misspecified, we prove that the corresponding model averaging estimator has asymptotic optimality, achieving the lowest possible Wasserstein distance. When there are correctly specified candidate models, we prove that our method asymptotically assigns all weights to the correctly specified models. Numerical results of extensive simulations and a real data analysis on intracerebral hemorrhage data strongly favour our method