Yongmin Chen

Equilibrium Product Bundling

This article offers an equilibrium theory of product bundling by rival firms. In several models where a primary good is produced in a duopoly market and one or more other goods is produced under perfectly competitive conditions, bundling is shown to emerge as an equilibrium strategy of one or both of the duopolists for its role as a product-differentiation device. When the rival firms can commit to bundling sales, their profits are higher but social welfare is reduced. Copyright 1997 by University of Chicago Press.

Price and Variety in the Spokes Model

The spokes model of nonlocalised spatial competition provides a new analytical tool for differentiated oligopoly and a representation of spatial monopolistic competition. An increase in the number of firms leads to lower equilibrium prices when consumers have relatively high product valuations, but, surprisingly, to higher equilibrium prices for intermediate consumer valuations. New entry alters consumer and social welfare through price, market expansion, and matching effects. With free entry, the market may provide too many or too few varieties from a social welfare perspective, and the equilibrium price remains above marginal cost even when the number of firms is arbitrarily large.

Paid Placement: Advertising and Search on the Internet

Paid placement, where advertisers bid payments to a search engine to have their products appear next to keyword search results, has emerged as a predominant form of advertising on the Internet. This paper studies a product-di¤erentiation model where consumers are initially uncertain about the desirability of and valuation for di¤erent sellers? products, and can learn about a seller?s product through a costly search. In equilibrium, a seller bids more for placement when his product is more relevant for a given keyword, and the paid placement of sellers by the search engine reveals information about the relevance of their products. This results in e¢ cient (sequential) search by consumers and increases total output.

Trade liberalization and strategic outsourcing

This paper develops a theory of strategic outsourcing that arises due to trade liberalization. With trade liberalization, a domestic firm may choose to purchase the intermediate good from a more efficient foreign producer, who also competes with the domestic firm in the final-good market. This can result in higher prices for both the intermediate and final goods. Although trade liberalization in the final product would lower the price of the final good, it could cause the price of the intermediate product to either increase or decrease, depending on the characteristics of the final products. Therefore, in the presence of strategic outsourcing, trade liberation can have ambiguous effects on consumer prices, depending on the relative tariff reductions for intermediate and final goods.

Asking Prices as Commitment Devices

This paper explores the implications of the hypothesis that an asking price is a ceiling to which a seller commits in order to provide incentives for potential buyers to incur search costs. Having attracted such a potential buyer, the seller must also determine how low to set the floor price, below which it is preferable to wait for another customer. This decision is affected by expectations about the characteristics of future buyers, which are, in turn, affected by the asking price. All of this is embedded in models of monopoly and of duopolistic competition. Copyright 1996 by Economics Department of the University of Pennsylvania and the Osaka University Institute of Social and Economic Research Association.

Parallel Imports in a Model of Vertical Distribution: Theory, Evidence and Policy

Parallel imports are goods traded without the authorization of an original trademark or copyright owner. In this paper, a model where parallel imports arise because of incentive problems in vertical distributions is discussed. A distributor receiving goods from a manufacturer at a low wholesale price can profitably sell the goods in another country, outside the authorized distribution channel. The manufacturer can limit such parallel imports by raising wholesale prices, but this reduces vertical pricing efficiency. Parallel imports can thus occur in equilibrium. The model is supported by empirical evidence from existing studies and new econometric work. Policy implications of the analysis are discussed.

On the Use of Ceiling-Price Commitments by Monopolists

The establishment of an asking, or ceiling, price from which reductions can be bargained is a common selling practice. For a monopolist seller of a single object, this article characterizes the best such ceiling price and shows that its use is optimal among all incentive-compatible mechanisms in a class of situations characterized by customers (1) who arrive one at a time and so do not compete with other directly and (2) who learn their idiosyncratic willingnesses to pay only by incurring idiosyncratic inspection costs.

Vertical Pricing and Parallel Imports

We generalize an earlier model of international vertical pricing to explain key features of parallel imports, or unauthorized trade in legitimate goods. When a manufacturer (or trademark owner) sells its product through an independent agent in one country, the agent may find it profitable to engage in parallel trade, selling the product to another country without the authorization of the manufacturer. Although parallel imports can be deterred when the manufacturers wholesale price is sufficiently high, there is a trade-off between improving vertical pricing efficiency and reducing parallel imports. In equilibrium, parallel imports can come from a country with higher retail prices, which is consistent with some factual data. While countries have varying interests in such a policy, restricting parallel imports tends to increase global welfare when trade cost is high, but may reduce welfare when trade cost is low. This finding suggests that open parallel trading regimes may be most appropriate within regional trade agreements.

The Effects of Competition on the Price for Cable Modem Internet Access

An important issue in economics is how market structure affects prices. While the standard view is that competition lowers prices, Chen and Riordan (2006) argued that with product differentiation it is not exceptional for prices to be higher under duopoly than monopoly. This paper empirically investigates one implication from Chen and Riordan, namely, that prices are lower under duopoly when consumer preferences for the two products are similar, and they are more likely to be higher under duopoly if consumer preferences for the two products are more diverse. Focusing on the price for cable modem Internet access, with or without competition from a digital subscriber line provider, and using education dispersion as a proxy for consumer preference diversity, we find empirical support for this implication. In markets where education dispersion is low, competition reduces prices. As education dispersion increases, the negative effect of competition on prices diminishes; and when the dispersion is high enough, competition increases prices.

PROFITABILITY OF PRODUCT BUNDLING

Using copulas to model the stochastic dependence of values, this article establishes new general conditions for the profitability of product bundling. A multiproduct monopolist generally achieves higher profit from mixed bundling than from separate selling if consumer values for two of its products are negatively dependent, are independent, or have sufficiently limited positive dependence. The profitability of monopoly bundling also extends to situations where a multiproduct firm competes with a single‐product rival.