This paper empirically examines the impact of entry by Wal-Mart on competition in the supermarket industry. Using a detailed panel dataset spanning 1994 to 2006, we estimate the impact of Wal-Mart on firm outcomes and market structure, controlling for persistent local trends and systematic...

National industrial concentration in the U.S. has risen sharply since the early 1980s, but there remains dispute over whether local geographic concentration has followed a similar trend. Using near population data from the Economic Censuses, we confirm and extend existing evidence on national...

Horizontal shareholding exists when significant shareholders have stock in horizontal competitors. (It is often imprecisely called "common shareholding," but that term can also apply when shareholders own stock in two noncompeting corporations. It differs from "cross-shareholding," which...

This Article shows that new economic proofs and empirical evidence provide powerful confirmation that, even when horizontal shareholders individually have minority stakes, horizontal shareholding in concentrated markets often has anticompetitive effects. The new economic proofs show that,...