Heterogeneous Firms in a Finite Directed Search Economy

We consider a directed search model for a finite economy with heterogeneous firms in two informational environments. In the first, the productivity of all firms is publicly observed. We prove existence of equilibria in pure posting strategies by firms and show that wage dispersion is driven by fundamentals. That is, more productive firms post higher wages and wage dispersion is absent when firms are homogeneous. When firms have heterogeneous productivities the equilibrium is not constrained efficient. In the second environment the productivity level of each firm is private information. The main results extend to this environment: Equilibria in pure strategies exist; strategies are increasing in productivity; and constrained efficiency does not obtain. When the productivity level of all firms is drawn from the same distribution, symmetric equilibria exist and the ranking of wages equals that of productivity.Directed Search, Labor Search, Market Power, Wage Differentials, Efficiency

On the game-theoretic foundations of competitive search equilibrium.

We provide a unified directed search framework with general production and matching specifications that encompass most of the existing literature. We prove the existence of subgame perfect Nash equilibria in pure firm strategies in a finite version of the model. We use this result to derive a more complete characterization of the equilibrium set for the finite economy and to extend convergence results as the economy becomes large to general production and matching specifications. The latter extends the microfoundations for the standard market utility assumption used in competitive search models with a continuum of agents to new environments.

A Model of Money with Multilateral Matching, Second Version

We develop a model of monetary exchange that avoids several common criticisms of the recent microfoundations literature. First, rather than random matching, we assume that buyers know the location of all sellers, and hence the process of finding a partner is deterministic, although trade is still stochastic since the number of buyers visiting a given seller is random. Second, given multilateral matching, rather than bargaining, we assume that goods are allocated according to second-price auctions. Third, given this mechanism, we do not have to assume agents can observe each other’s money holdings or preferences, as is necessary for tractability with bargaining. A novel result is that homogeneous buyers hold different amounts of money, leading to equilibrium price dispersion. We find the closed-form solution for the distribution of money holdings. We characterize equilibrium and efficient monetary policy.Search Theory of Money, Budget Constrained Auctions, Friedman Rule

Directed Search with Multiple Job Applications

We develop an equilibrium directed search model of the labor market where workers can simultaneously apply for multiple jobs. The main result is that all equilibria exhibit wage dispersion despite the fact that workers and firms are homogeneous. Wage dispersion is driven by the simultaneity of application choice. Risk-neutral workers apply for both ‘safe’ and ‘risky’ jobs. The former yield a high probability of a job offer, but for low pay, and act as a fallback option; the latter provide with higher potential payoff, but are harder to get. Furthermore, the density of posted wages is decreasing, consistent with stylized facts. Unlike most directed search models, the equilibria are not constrained efficient.

Market Power and Efficiency in a Search Model

We build a theoretical model to study the welfare effects and resulting policy implications of firms’ market power in a frictional labor market. Our environment has two main characteristics: wages play a role in allocating labor across firms and there is a finite number of agents. We find that the decentralized equilibrium is inefficient and that the firms’ market power results in the misallocation of workers from the high to the low-productivity firms. A minimum wage forces the low-productivity firms to increase their wage, leading them to hire even more often thereby exacerbating the inefficiencies. Moderate unemployment benefits can increase welfare because they limit firms’ market power by improving the workers’ outside option.directed search, heterogeneity, inefficient allocation, market power

A Structural Model of the Retail Market for Illicit Drugs

We estimate a model of illicit drugs markets using data on purchases of crack cocaine. Buyers are searching for high-quality drugs, but they determine drugs’ quality (i.e., their purity) only after consuming them. Hence, sellers can rip off first-time buyers or can offer higher-quality drugs to induce buyers to purchase from them again. In equilibrium, a distribution of qualities persists. The estimated model implies that if drugs were legalized, in which case purity could be regulated and hence observable, the average purity of drugs would increase by approximately 20 percent and the dispersion would decrease by approximately 80 percent. Moreover, increasing penalties may raise the purity and affordability of the drugs traded by increasing sellers’ relative profitability of targeting loyal buyers versus first-time buyer

The challenge of trade adjustment in Greece

Greece's trade deficit declined by 10 percent of gross domestic product (GDP) between 2007 and 2012, removing one of the great economic imbalances of the pre-crisis years. However, this reduction was achieved exclusively through import compression while exports fell over that period, thereby worsening the economic crisis. This chapter studies Greece's export underperformance in comparison to Ireland, Portugal and Spain as well as Greece's own pre-crisis experience. The main findings are that (1) given past performance, Greece's exports should have increased by 25 percent, rather than drop by 5 percent between 2007 and 2012; (2) labor markets have adjusted to the new economic environment; (3) product markets did not adjust, hindering the recovery of competitiveness; (4) export underperformance is responsible for a third of the decline in GDP since 2007. The chapter concludes that the business environment and firm size distribution in Greece are also hindering the necessary adjustment.</p

A Search-Theoretic Model of the Retail Market for Illicit Drugs

A search-theoretic model of the retail market for illegal drugs is developed. Trade occurs in bilateral, potentially long-lived matches between sellers and buyers. Buyers incur search costs when experimenting with a new seller. Moral hazard is present because buyers learn purity only after a trade is made. The model produces testable implications regarding the distribution of purity offered in equilibrium, and the duration of the relationships between buyers and sellers. These predictions are consistent with available data. The effectiveness of different enforcement strategies is evaluated, including some novel ones which leverage the moral hazard present in the market.