The balance of probabilities vs. the balance of harms in merger control

Abstract

I examine the difference between the balance of probabilities and the balance of harms standards in merger control. I show that both standards take into account the entire distribution of post-merger outcomes, but the former focuses on the median outcome whereas the latter focuses on the mean outcome. Consequently, a shift from a balance of probabilities to a balance of harms standard broadens the set of mergers that are blocked if the distribution of post-merger outcomes is skewed to the left and conversely if it is skewed to the right.