| By: | Ellickson, Paul | 
| Abstract: | This paper uses a model of endogenous sunk cost (ESC) competition to explain 
the industrial structure of the supermarket industry, where a few powerful 
chains provide high quality products at low prices. The predictions of this 
model accord well with the features of the supermarket industry documented 
here. Using a novel dataset of store level observations, I demonstrate that 1) 
the same number of high quality firms enter markets of varying sizes and 
compete side by side for the same consumers and 2) quality increases with the 
size of the market. In addition to documenting a local structure of 
competition consistent with the ESC framework, I demonstrate that the choice 
of quality by rival firms behaves as a strategic complement. This key finding, 
which is consistent with an ESC model of quality enhancing sunk outlays, 
eliminates several alternative explanations of concentration in the 
supermarket industry, including most standard models of cost-reducing 
investment and product proliferation. These results suggest that the 
competitive mechanisms sustaining high levels of concentration in the 
supermarket industry are inherently rivalrous and unlikely to lead to the 
emergence of a single dominant firm. | 
| Keywords: | endogenous sunk costs, vertical product differentiation, oligopoly, retail, supermarkets, market concentration, dartboard, complementarity | 
| JEL: | L13 L22 L81 | 
| Date: | 2005 | 
| URL: | http://d.repec.org/n?u=RePEc:duk:dukeec:05-04&r=com |