Dynamic sorting in durable goods markets with buyer heterogeneity

In a competitive dynamic durable good market where sellers have private information about quality, I identify certain inefficiencies that arise due to heterogeneity in buyers' valuations. Even if the market induces dynamic sorting among sellers and all goods are eventually traded, inefficiency can arise because high valuation buyers buy early when low‐quality goods are sold, while high‐quality goods are allocated to low valuation buyers that buy later. This misallocation adds to the inefficiency caused by delay in trading. Under certain circumstances, high‐quality goods may never be traded as in a static market.     

Simple Reputation Systems*

We develop a model of simple “reputation systems” that monitor and publish information about the behavior of sellers in a search market with asymmetric information. The reputations created influence the equilibrium search patterns of buyers and thus provide for market‐based “punishment” of bad behavior. We show that a reputation system that rewards honesty can enhance welfare by allowing good sellers to truthfully signal their type. However, the same system can be prone to strategic manipulation by sellers who always have low‐quality products. In that case, we show that an alternative system which assigns reputations based on product quality rather than honesty can be superior.     

COMPENSATION FOR QUALITY DIFFERENCE IN A SEARCH MODEL OF MONEY*

We study an economy in which there is always double coincidence of wants, agents have perfect information about qualities of goods, and there are no transaction costs. The hold‐up problem arises because efforts invested in improving quality prior to search may not be compensated in the market. Situations in which barter fails to motivate quality improvement are identified. With money, however, the extra effort in quality improvement will be compensated when high‐quality good producers trade with agents holding both the low‐quality good and money. Injection of money can induce almost all agents to produce the high‐quality good.     

STRATEGIC ADVERTISING AND DIRECTED SEARCH

Imperfect observability and costly informative advertising are introduced into a standard directed search framework. Capacity‐constrained sellers send costly advertisements to direct buyers' uncoordinated search by specifying their location and terms of trade. We show that the equilibrium advertising intensity is nonmonotonic in the buyer–seller ratio. In addition, we also find that price posting dominates auctions since both mechanisms yield the same expected revenue, but the latter results in higher advertising expense. Finally, we find a positive comovement between market transparency and price for low market tightness when the measure of informed buyers is endogenous.     

INFLATION AND THE DISPERSION OF REAL WAGES*

The article studies the effects of inflation on real wage dispersion in a search‐monetary framework. The economy is characterized by frictions in both the goods and the labor markets. In the goods market, buyers and sellers bargain over prices, whereas in the labor market firms post wage offers. In equilibrium, a lower inflation rate increases the dispersion of real wages. This result is consistent with both the observed trends in wage dispersion and the inflation rate witnessed in the 1980s and the 1990s in the United States and the empirical literature linking reduced inflation to greater wage dispersion.     

Competitive search markets for durable goods

Summary. This paper considers a dynamic version of Akerlof's (1970) lemons problem where buyers and sellers must engage in search to find a trading partner. We show that if goods are durable, the market itself may provide a natural sorting mechanism. In equilibrium, high-quality goods sell at a higher price than low-quality goods but also circulate longer. This accords with the common wisdom that sellers who want to sell fast may have to accept a lower price. We then compare the equilibrium outcomes under private information with those under complete information. Surprisingly, we find that for a large range of parameter values the quilibrium outcomes under the two information regimes coincide, despite the fact that circulation time is used to achieve separation. Received: August 24, 2000; revised version: October 24, 2000     

Pricing and signaling with frictions

We study a market where each seller chooses the quality and price of goods and the number of selling sites. Observing sellers? choices of prices and sites, but not quality, buyers choose which site to visit. A seller?s choices of prices can direct buyers? search and signal quality. A unique equilibrium exists and is separating. When the quality differential is large, the equilibrium implements the efficient allocation with public information. Otherwise, the quality of goods and/or the number of sites created is inefficient, due to a conflict between the search-directing and signaling roles of prices.     

STRATEGIC TRADE AND DELEGATED COMPETITION WITH ENDOGENOUS QUALITY CHOICE: IS EXPORT POLICY NEEDED?

This paper introduces the relative‐performance contract into a vertically differentiated product market and examines how the optimal trade policy and quality choice respond to the incentive mechanism. We find that the high quality firm makes better use of the delegation than the low quality firm in a cross‐border decentralized model. The main difference between the present paper and the strategic trade theory literature is that in this paper the optimal policy is free trade, which does not depend on whether firms compete by prices or quantities, and on whether the goods are substitutes or full complements.     

DYNAMIC TRADING IN A DURABLE GOOD MARKET WITH ASYMMETRIC INFORMATION*

We analyze a dynamic version of the Akerlof–Wilson “lemons” market in a competitive durable good setting. There is a fixed set of sellers with private information about the quality of their wares. The price mechanism sorts sellers of different qualities into different time periods—prices and average quality of goods traded increase over time. Goods of all qualities are traded in finite time. Market failure arises because of the waiting involved—particularly for sellers of better quality. The equilibrium path may exhibit intermediate breaks in trading.     

DECENTRALIZED TRADE MITIGATES THE LEMONS PROBLEM*

In markets with adverse selection, only low‐quality units trade in the competitive equilibrium when the average quality of the good held by sellers is low. We show that under decentralized trade, however, both high‐ and low‐quality units trade, although with delay. Moreover, when frictions are small, the surplus realized is greater than the (static) competitive surplus. Thus, decentralized trade mitigates the lemons problem. Remarkably, payoffs are competitive as frictions vanish, even though both high‐ and low‐quality units continue to trade, and there is trade at several prices.     

Search costs and the severity of adverse selection

In view of some recent empirical evidence, I suggest a relationship between the magnitude of search costs and the severity of adverse selection in the context of a dynamic model with asymmetric information. In markets with small search costs sellers with low quality products misrepresent their quality and demand a high price. If search costs are not negligible, sellers׳ price offers are truthful and all product qualities are traded over time. In markets with small search costs, a budget balanced mechanism can mitigate adverse selection: sellers should pay a per period market participation tax and receive a rebate after trading.     

COMMITMENT AND COSTLY SIGNALING IN DECENTRALIZED MARKETS

I propose a search model of a decentralized market with asymmetric information in which sellers are unable to commit to asking prices announced ex ante. Relaxing the commitment assumption prevents sellers from using price posting as a signaling device to direct buyers' search. Private information about the gains from trade and inefficient entry on the demand side then contribute to market illiquidity. Endogenous sorting among costly marketing platforms can facilitate the search process by segmenting the market to alleviate information frictions. Seemingly irrelevant but incentive compatible listing fees are implementable provided that the market is not already sufficiently active.     

Middle Men: The Visible Market‐Makers

This paper presents a framework in which middlemen emerge to intermediate between ex‐ante homogeneous buyers and sellers in the presence of search frictions. Middlemen announce prices, and hold an inventory to provide more sure services. Middlemen can mitigate trade imbalances with price competition. Using this framework I illustrate how the frictionless limit can emerge and how middlemen can implement the short‐side principle for the market price to be Walrasian. The recent progress in the literature on intermediation will also be discussed.     

Trading networks with price-setting agents

In a wide range of markets, individual buyers and sellers trade through intermediaries, who determine prices via strategic considerations. Typically, not all buyers and sellers have access to the same intermediaries, and they trade at correspondingly different prices that reflect their relative amounts of power in the market. We model this phenomenon using a game in which buyers, sellers, and traders engage in trade on a graph that represents the access each buyer and seller has to the traders. We show that the resulting game always has a subgame perfect Nash equilibrium, and that all equilibria lead to an efficient allocation of goods. Finally, we analyze trader profits in terms of the graph structure — roughly, a trader can command a positive profit if and only if it has an “essential” connection in the network, thus providing a graph-theoretic basis for quantifying the amount of competition among traders.     

Market entry and trade weighted import costs

Trade weighting is a common method of aggregating trade frictions. It will understate changes in these costs when there are non‐ad valorem trade costs and quality differences. Newly traded goods enter at higher trade costs than previously traded ones. Lower import costs shift trade to low‐quality goods with higher measured trade costs. These effects are quantitatively important. U.S. import costs fall more than twice as fast as trade weighted measures from 1974 to 2004 after the impact of shifting quality and newly traded goods is accounted for. Empirical estimates that use trade weighting will underestimate the welfare impact of trade costs.     

ADVERSE SELECTION IN DYNAMIC MATCHING MARKETS

We study the Akerlofian adverse selection problem in a dynamic matching model where the competitive situation varies across different meetings. The ‘lemons principle’ is shown to limit the high quality sales within a wider range of quality distributions than in the Walrasian benchmark. High quality goods can nevertheless be traded, albeit less frequently than the low quality goods. For certain quality distributions, there exists a ‘partially pooling’ steady state where high quality sellers are active whenever at least two buyers compete for the good. Otherwise, the model features cycles in a sense that high quality goods are traded only in non‐consecutive periods.     

Income distribution and exchange in a dynamic search model

This paper studies the link between income distribution and trade mechanisms in a dynamic search model with two-sided asymmetric information. Buyers and sellers have imperfect information about the income levels of the other group. Furthermore, asymmetry of information about incomes is the source of price dispersion. In such a frictional environment, we capture the effects of a change in inter- and intra-class income distribution on the trade mechanism, which is represented by the expected trade volume and the flux of buyers and sellers in the market.     

Internet Technology and the Extensive Margin of Trade: Evidence from eBay in Emerging Economies

Online platforms such as eBay offer technologies that make it easier for firms to export. This paper dissects a new firm‐level dataset that covers sales made through eBay by sellers based in 21 emerging economies to provide a new lens through which to look at the effect of trade costs on the extensive margin of trade. Comparing eBay sellers with “offline” firm‐level data from the World Bank's Exporter Dynamics Database allows us to test whether the observed trade patterns on eBay fit with the trade‐liberalization predictions of heterogeneous‐firm models. We find that eBay firms export to more destinations, suggesting low destination‐specific fixed costs on eBay. We then show that the distribution of export destinations across eBay sellers is well approximated by a balls‐and‐bins model of frictionless trade, suggesting eBay indeed lowers fixed export costs. Finally, we compare the gravity of eBay with that of offline trade and find geographic distance, languages, and trade agreements to matter less for online trade.     

Motivated sellers and predation in the housing market

We develop an equilibrium search model of the housing market where sellers may become distressed as they are unable to sell. A unique steady state equilibrium exists where distressed sellers attempt liquidation sales by accepting prices that are substantially below fundamental values. During periods where a large number of sellers are forced to liquidate customers exhibit ‘predation’: they hold off purchasing and strategically slow down the speed of trade, which in turn causes more sellers to become distressed. The model naturally suggests several proxies of liquidity. Interestingly, the average time on the market (TOM), one of the most frequently used statistics in the literature, does a poor job within the context of liquidation sales and predation. Specifically we show that TOM falls during periods of predatory buying, which, if interpreted on face value, indicates that the market becomes more liquid with predation. We propose an alternative proxy – the profit loss in fire sales – which appears to be a more robust measure of liquidity than TOM.     

A structural model of competing sellers: Auctions and posted prices

In an original data set of goods listed for sale online, I observe that both auctions and posted prices are popular with buyers and sellers in the compact-disc market. To explain why these two mechanisms coexist, I estimate a structural model of competing sellers who differ in the value of their outside options. Buyers are allowed to value auctioned and posted-price goods differently but the estimated value distributions suggest that differences across buyers do not explain the mechanism coexistence that I observe. In contrast, differences across sellers' outside options are important: the value of the outside option segments the market with high outside-option sellers choosing to post a fixed price. There are two key forces at work that drive this empirical result. First, competition between sellers favors coexistence over an auction-only or a posted-price-only marketplace because sellers prefer to be in a market with fewer rivals. Second, sellers with more valuable outside options prefer the posted-price mechanism because posted-price goods sell less often than auctioned goods but at a higher price. As a result, a larger outside option reduces the loss from not selling and favors the posted-price mechanism.