The Double Diamond Paradox
We study vertical relations in markets with consumer and retailer search. We obtain three important new results. First, we provide a novel explanation for price dispersion that does not depend on some form of heterogeneity among consumers. Price dispersion takes on the form of a bimodal distribution. Second, under competitive conditions (many retailers or small consumer search cost), social welfare is significantly smaller than in the double marginalization outcome. Manufacturers' regular price is significantly above the monopoly price, squeezing retailers' markups and providing an alternative explanation for incomplete cost pass-through. Third, firms' prices are decreasing in consumer search cost.
Contemporary domination of chain-stores in retailing is modeled, perceiving a monopolistic retailer as a market leader. A myriad of her suppliers compete in a monopolistic competitive sector, displaying quadratic consumers’ preferences for a differentiated good. The leader announces her markup before the suppliers choose their prices/quantities. She may restrict the range of suppliers or allow for free entry. Then, a market distortion, stemming from double marginalization and excessive variety would be softened whenever the government allows the retailer to apply an entrance fee to the suppliers, or/and per-quantity sales subsidies (doing the opposite to usual Russian regulation).
We study how a monopoly manufacturer optimally manages her contractual relations with retailers in markets with consumer search. By choosing wholesale prices, the manufacturer affects the degree of competition between retailers and the incentives of consumers to search. We show that depending on whether or not the manufacturer can commit to her price decisions and on the search cost, the manufacturer may be substantially better off choosing her wholesale prices not independent of each other, consciously allowing for asymmetric contracts. Thus, our analysis may shed light on when we may expect sales across different retailers to be positively or negatively correlated. Our model may be able to generate loss leaders at the wholesale level and show the rationale for creating “premium resellers”.