LARGE IS BEAUTIFUL: HORIZONTAL MERGERS FOR BETTER EXPLOITATION OF PRODUCTION SHOCKS.

The profitability of horizontal mergers is investigated in a situation in which firms face a production shock and therefore are uncertain about their future costs. I show that, due to production rationalization, small-scale mergers can be profitable if the uncertainty is large. The efficiency gain in production also implies benign welfare consequences. Under cost uncertainty, a profitable merger always improves social welfare if no more than half of the industry's firms are allowed to merge. Finally, I show that the incentives to merge depend on the information structure. Firms are less likely to merge when they possess more information. [ABSTRACT FROM AUTHOR]