This study examines how much, if any, of the differences in retail gasoline prices between markets is attributable to differences in the composition of vertical contract types at gasoline stations in each market. The purchase of the independent retail gasoline chain, Thrifty, by ARCO provides a unique opportunity to examine the effects of changes in different vertical contract types on local retail prices. This event caused sharp changes in the market share of i) fully vertically integrated stations, and ii) independent stations; differentially affecting local markets in the Los Angeles and San Diego Metropolitan areas. Using unique and detailed station-level data, this study examines how these sharp changes affected local retail prices. The detailed data and the research design based on the Thrifty station conversions allow for credible estimation of the effects of the market share of independent retailers and vertically integrated retailers on local market prices, controlling for any omitted factors at the station level, and the city level over time. Results for the Los Angeles and San Diego metropolitan areas indicate that a decrease in the market share of independent stations has a significant positive impact on local retail price. However, a change in the market share of refiner owned and operated branded stations does not have a significant impact on local market price. These results have important implications as policy makers consider the regulation of vertical contracts as a means to increase competition in gasoline markets. The research design and detailed data also allow for inference on the underlying nature of retail gasoline competition.

This paper explores the relationship between the structure of the market for the refining and distribution of gasoline and the wholesale price of unbranded gasoline sold to independent gasoline retailers. Theoretically, the effect of an increase in vertical integration is ambiguous because opposing forces act to increase and decrease wholesale prices. We empirically examine the effects of vertical and horizontal market structures on wholesale prices using both a broad panel and an event analysis. The panel covers twenty-six metropolitan areas from January 1993 through June 1997. The event is a merger of Tosco and Unocal in 1997 that changed the vertical and horizontal structure of thirteen West Coast metropolitan areas. Both data sets show that an increase in the degree of vertical integration is associated with higher wholesale prices

This paper explores the relationship between the structure of the market for the refining and distribution of gasoline and the wholesale price of unbranded gasoline sold to independent gasoline retailers. Theoretically, the effect of an increase in vertical integration is ambiguous because opposing forces act to increase and decrease wholesale prices. We empirically examine the effects of vertical and horizontal market structures on wholesale prices using both a broad panel and an event analysis. The panel covers twenty-six metropolitan areas from January 1993 through June 1997. The event is a merger of Tosco and Unocal in 1997 that changed the vertical and horizontal structure of thirteen West Coast metropolitan areas. Both data sets show that an increase in the degree of vertical integration is associated with higher wholesale prices.

This paper examines the importance of income effects in purchase decisions for every-day products by analyzing the effect of gasoline prices on grocery expenditures. Using detailed scanner data from a large grocery chain as well as data from the Consumer Expenditure Survey (CES), we show that consumers re-allocate their expenditures across and within food-consumption categories in order to offset necessary increases in gasoline expenditures when gasoline prices rise. We show that gasoline expenditures rise one-for-one with gasoline prices, consumers substitute away from food-away-from-home and towards groceries in order to partially offset their increased expenditures on gasoline, and that within grocery category, consumers substitute away from regular shelf-price products and towards promotional items in order to save money on overall grocery expenditures. On average, consumers are able to decrease the net price paid per grocery item by 5-11% in response to a 100% increase in gasoline prices. We find evidence that this consumer substitution effect happens given retail price adjustments due to pass-though of higher gasoline prices into retail prices, by investigating two price indexes; one that uses shelf-prices and one that uses prices net of promotional discounts (net-prices are equal to shelf-prices if there is no discount). We assess the effect of gasoline prices on each of the price indexes, controlling for store-level fixed-effects and regional time trends, finding a 5 percent increase in net prices as a result of a 100 percent increase in gasoline prices. Product prices appear to adjust flexibly with gasoline prices through the size of discounts and promotions, which change weekly (or by-weekly) even though shelf-prices remain stable. Our results show that consumers respond to permanent changes in income from gasoline prices by substituting towards lower-cost food at the grocery store and lower priced items within grocery category. The substitution away from full-priced items towards sale items has implications for microeconomic demand models as well as for macroeconomic inflation measures that typically do not incorporate frequently changing promotional prices.

The 1990 Clean Air Act Amendments stipulated gasoline content requirements for metropolitan areas with air pollution levels above predetermined federal thresholds. The legislation led to exogenous changes in the type of gasoline required for sale across U.S. metropolitan areas. This paper uses a panel of detailed wholesale gasoline price data to estimate the effect of gasoline content regulation on wholesale prices and price volatility. We investigate the extent to which the estimated price effects are driven by changes in the number of suppliers versus geographic segmentation resulting from regulation. We find that prices in regulated metropolitan areas increase significantly, relative to a control group, by an average of 3 cents per gallon. The price effect, however, varies by 8 cents per gallon across regulated markets and the heterogeneity across markets is correlated with the degree of geographic isolation generated by the discontinuous regulatory requirements.