Price dispersion and seller heterogeneity in retail food markets

Price dispersion, i.e. a homogeneous product being sold at different prices by different sellers, is among the most replicated findings in empirical economics. The paper assesses the extent and determinants of spatial price dispersion for 14 perfectly homogeneous food products in more than 400 retailers in a market characterized by the persistence of a large number of relatively small traditional food stores, alongside large supermarkets. The extent of observed price dispersion is quite high. When prices in an urban area (where the spatial concentration of sellers is higher) are compared with those in smaller towns and rural areas, differences in search costs and the potentially higher degree of competition do not yield lower prices. Other counteracting factors, including differences in seller costs and consumer incomes, make prices, on average, higher in the urban area for 11 of the 14 products considered. For many, but not all, the products supermarkets proved to be less expensive than traditional retailers, although average savings from food shopping at supermarkets were extremely low. Finally, the results of the study provide evidence that retailers have different pricing strategies and these differences also emerge for supermarkets belonging to the same chain. The results presented in the paper suggest that a variety of factors play a role in explaining price dispersion. In addition to differences in seller costs, the contemporaneous heterogeneity of retailers (in terms of services provided) and consumers (in terms of search costs and preferences) makes the emergence of monopolistic competition possible as well as allowing small traditional food retailers to remain in business.