market definition such as “acute in-patient care” averages out severe discrepancies that become visible when concentration is … only impact on the level of concentration, while the correlation remains high. Our results underline the need for more …

A rapidly growing literature has shown that market concentration among domestic firms has increased in the United … measures of concentration, once adjusted for sales by foreign exporters, actually stayed constant between 1992 and 2012. We … reconcile these findings by linking part of the increase in domestic concentration to import competition. Although concentration …

We use transaction-level data to study changes in the concentration of US imports. Concentration has fallen in the … typical industry, while it is stable by industry and country of origin. The fall in concentration is driven by the extensive … concentration among national producers. …

We use transaction-level data to study changes in the concentration of US imports. Concentration has fallen in the … typical industry, while it is stable by industry and origin country. The fall in concentration is driven by the extensive … firms within country are diverging. Finally, higher concentration from an origin country is associated with a fall in prices …

concentration. In contrast, competition enforces innovation, i.e. sales concentration has a negative impact on R&D. …