Credit mismatch and breakdown

This paper studies the phenomenon of mismatch in a decentralized credit market where borrowers and lenders must engage in costly search to establish credit relationships. Our dynamic general equilibrium framework integrates incentive based informational frictions with a matching process highlighted by (i) borrowers' endogenous market entry and exit decision (entry frictions) and (ii) time and resource costs necessary to locate credit opportunities (search frictions). A key feature of the incentive compatible loan contract negotiated between borrowers and lenders is the interaction of informational frictions (in the form of moral hazard) with entry and search frictions. We find that the removal of entry barriers can eliminate incentive-based equilibrium credit rationing. More generally, entry and incentive frictions are important in understanding the extent of credit rationing and credit mismatch, while search and incentive frictions are important for understanding credit market breakdown.     

Matching markets with adverse selection

This paper considers a market with adverse selection in the spirit of Rothschild and Stiglitz (Quart. J. Econ. 90 (1976) 629). The major departure from existing approaches is that we model a decentralized market that is open-ended and constantly refilled by new participants, e.g., by new workers and firms in the case of a labor market. The major novelty of this approach is that the distribution of types in the market becomes an endogenous variable, which is jointly determined with equilibrium contracts. As frictions become small, we show that the least-cost separating contracts are always supported as an equilibrium outcome, regardless of the distribution of types among entrants. Moreover, we derive conditions under which this outcome is also unique.     

The law of one price revisited: How do goods market frictions generate large and volatile price deviations?

This paper analyzes the role of goods market frictions in accounting for the large and volatile deviations from the Law of One Price (LOP) in a framework of flexible prices. We draw a distinction between the goods market frictions that are required to consume tradable goods (e.g., distribution costs) and those that are necessary for international transactions (e.g., trade costs). We find that trade costs generate LOP deviations by introducing a no-arbitrage band, while distribution costs cause the price to deviate from the LOP by affecting the probability that trade will occur, given the band. We then conduct a Monte Carlo simulation to show that real exchange rate volatility is positively associated with trade costs, but negatively related to distribution costs. This effect depends on the interplay of trade costs and distribution costs, as they work in opposite directions when creating arbitrage opportunities.     

Search costs and efficiency: Do unemployed workers search enough?

Many labor market policies affect the marginal benefits and costs of job search. The impact and desirability of such policies depend on the distribution of search costs. In this paper, we provide an equilibrium framework for identifying the distribution of search costs and we apply it to the Dutch labor market. In our model, the wage distribution, job search intensities, and firm entry are simultaneously determined in market equilibrium. Given the distribution of search intensities (which we directly observe), we calibrate the search cost distribution and the flow value of non-market time; these values are then used to derive the socially optimal firm entry rates and distribution of job search intensities. From a social point of view, some unemployed workers search too little due to a hold-up problem, while other unemployed workers search too much due to coordination frictions and rent-seeking behavior. Our results indicate that jointly increasing unemployment benefits and the sanctions for unemployed workers who do not search at all can be welfare-improving.     

Maximum likelihood estimation of search costs

In a recent paper Hong and Shum [2006. Using price distributions to estimate search costs. Rand Journal of Economics 37, 257-275] present a structural method to estimate search cost distributions. We extend their approach to the case of oligopoly and present a new maximum likelihood method to estimate search costs. We apply our method to a data set of online prices for different computer memory chips. The estimates suggest that the consumer population can be roughly split into two groups which either have quite high or quite low search costs. Search frictions confer a significant amount of market power to the firms: Despite more than 20 firms operating in each of the markets, we estimate price-cost margins to be around 25%. The paper also illustrates how the structural method can be employed to simulate the effects of the introduction of a sales tax.     

SEARCH DIRECTION AND WAGE DISPERSION*

In a directed search model, we allow the unemployed and the vacancies to choose whether to send or receive wage offers. This determines the market structure. There are several equilibria but a unique evolutionary stable one. Wage offers are made under incomplete information about the number of offers, and the equilibrium strategies involve mixing. This results in wage dispersion. We show that if the unemployment–vacancy ratio is close to unity, the stable equilibrium consists of two submarkets with opposite search directions. Otherwise, the long side of the market sends offers. The stable equilibrium is efficient, given the frictions.     

Labour markets, liquidity, and monetary policy regimes

Abstract.  We develop an equilibrium model of the monetary policy transmission mechanism that highlights information frictions in the market for money and search frictions in the labour market. The information friction increases the persistence in the response of interest rates following monetary policy regime shifts. This occurs because agents have incomplete information about the nature of the shifts and optimally update their inflation forecasts using an 'adaptive' expectations rule. The search friction transmits the interest rate movements to the labour market by affecting job creation activities; together, the two frictions imply that unemployment reacts very gradually to monetary policy shocks. JEL Classification: E4, E5     

Search frictions, market power, and long-run growth

This paper embeds product market search in an Ak growth model to study the effects of search frictions on market structure, capital accumulation, and long-run growth. The basic hypothesis is that search frictions, in giving rise to market power, result in higher prices and lower output levels. The falling demand for capital stemming from firms cutting back output then lowers the interest rate, dampening capital accumulation and slowing down growth. A decline in search frictions sets the process in reverse, eventually speeding up growth through the change in market structure. In the meantime, the stock market values of firms could fall.     

Subsidy competition and imperfect labor markets

This study presents a two‐country model of subsidy competition for manufacturing firms under labor market imperfections. Because subsidies affect the distribution of firms, subsidies influence unemployment rates and welfare in both countries. We show that when labor market frictions are high, subsidy competition is beneficial, although subsidies under subsidy competition are inefficiently high. In the coordinated equilibrium, the supranational authority provides a subsidy to firms that equal the expected total search costs, which increases the number of firms relative to laissez‐faire and improves welfare relative to laissez‐faire and subsidy competition. Finally, we find that a rise in a country's labor market frictions raises the equilibrium subsidy rate, affects unemployment rates, and lowers welfare.     

Alternative theories of wage dispersion

We analyze labor market models where the law of one price fails—i.e., models with equilibrium wage dispersion. We begin considering ex ante heterogeneous workers, but highlight a problem with this approach: If search is costly the market shuts down. We then assume homogeneous workers but ex post heterogeneous matches. This model is robust to search costs, and delivers equilibrium wage dispersion. However, we prove that the law of two prices holds: Equilibrium implies at most two wages. We explore other models, including one combining ex ante and ex post heterogeneity which is robust and delivers more realistic wage dispersion.     

Holdups and Efficiency with Search Frictions

A natural holdup problem arises in a market with search frictions: Firms have to make a range of investments before finding their employees, and larger investments translate into higher wages. In particular, when wages are determined by ex post bargaining, the equilibrium is always inefficient: Recognizing that capital-intensive production relations have to pay higher wages, firms reduce their investments. This can only be prevented by removing all the bargaining power from the workers, but this, in turn, depresses wages below their social product and creates excessive entry of firms. In contrast to this benchmark, we show that efficiency is achieved when firms post wages and workers can direct their search toward more attractive offers. This efficiency result generalizes to an environment with imperfect information where workers only observe a few of the equilibrium wage offers. We show that the underlying reason for efficiency is not wage posting per se, but the ability of workers to direct their search toward more capital-intensive jobs.     

Can EconJobMarket help Canadian universities?

We analyze the academic matching market by considering a simple model in which applicants who face an application cost strategically choose portfolios of applications. Universities then play a decentralized offer game in which unaccepted offers result in failure to trade on both sides of the market. We characterize a basic equilibrium to illustrate the sorting role that application costs play. In a numeric example, we illustrate how reduced application costs can result in increased matching frictions.     

Internal rationality, imperfect market knowledge and asset prices

We present a decision theoretic framework in which agents are learning about market behavior and that provides microfoundations for models of adaptive learning. Agents are ‘internally rational’, i.e., maximize discounted expected utility under uncertainty given dynamically consistent subjective beliefs about the future, but agents may not be ‘externally rational’, i.e., may not know the true stochastic process for payoff relevant variables beyond their control. This includes future market outcomes and fundamentals. We apply this approach to a simple asset pricing model and show that the equilibrium stock price is then determined by investors? expectations of the price and dividend in the next period, rather than by expectations of the discounted sum of dividends. As a result, learning about price behavior affects market outcomes, while learning about the discounted sum of dividends is irrelevant for equilibrium prices. Stock prices equal the discounted sum of dividends only after making very strong assumptions about agents? market knowledge.     

Do search frictions matter for inflation dynamics?

We assess the empirical relevance for inflation dynamics of accounting for the presence of search frictions in the labor market. The new Keynesian Phillips curve explains inflation as being mainly driven by current and expected future marginal costs. Recent empirical research has emphasized different measures of real marginal costs to be consistent with observed inflation persistence. We argue that, allowing for search frictions in the labor market, real marginal cost should also incorporate the cost of generating and maintaining long-term employment relationships, along with conventional measures, such as real unit labor costs. In order to construct a synthetic measure of real marginal costs, we use newly available labor market data on worker finding and separation rates that reflect hiring and firing costs. We then estimate a new Keynesian Phillips curve by generalized method of moments (GMM) using the imputed marginal cost series as an observable and find that the contribution of labor market frictions in explaining inflation dynamics is small.     

The (Q,S,s) pricing rule: a quantitative analysis

Are nominal prices sticky because menu costs prevent sellers from continuously adjusting their prices to keep up with inflation or because search frictions make sellers indifferent to any real price over some non-degenerate interval? The paper answers the question by developing and calibrating a model in which both search frictions and menu costs may generate price stickiness and sellers are subject to idiosyncratic shocks. The equilibrium of the calibrated model is such that sellers follow a (Q,S,s) pricing rule: each seller lets inflation erode the effective real value of the nominal prices until it reaches some point s and then pays the menu cost and sets a new nominal price with an effective real value drawn from a distribution with support [S, Q], with s < S < Q. Idiosyncratic shocks short-circuit the repricing cycle and may lead to negative price changes. The calibrated model reproduces closely the properties of the empirical price and price-change distributions. The calibrated model implies that search frictions are the main source of nominal price stickiness.     

Holdup, search, and inefficiency

This paper investigates the holdup problem in the search market environment where players search for their trading partners and specific investments are made after matching but before trade decisions are taken. We show that markets with small frictions make the holdup problem more serious than those with large frictions because in any equilibrium, whether stationary or nonstationary, investment must reach the minimum level and trade must be delayed with positive probability for infinitely many time periods. We then show that the gap between equilibrium welfare and the first best welfare becomes larger as search frictions become smaller.     

Financial frictions and the futures pricing puzzle

In perfect capital markets, the futures price of an asset should be an unbiased forecast of its realized spot price when the contract matures. In reality, futures prices are often higher for some assets and lower for others. However, there is no stability in the relationship between futures prices and the realized spot prices. This instability has been a puzzle in the existing financial literature. The key to this puzzle may lie in the nature of the model and the lack of market imperfections. In this study, we take a theoretical approach in a dynamic multi-period environment. We incorporate competition between disparate economic agents and impose financial frictions (i.e., imperfections) that are in the form of hedging and borrowing limits on them. Our model gives rise to multiple equilibria, each with unique market clearing prices, with the market switching between these equilibria. Our analysis incorporates a comprehensive consideration of the risks faced by the futures markets participants (i.e., speculators and hedgers) and leads to a better understanding of the puzzle.     

Search, migration, and urban land use: The case of transportation policies

We develop a search-matching model with rural-urban migration and an explicit land market. Wages, job creation, urban housing prices are endogenous and we characterize the steady-state equilibrium. We then consider three different policies: a transportation policy that improves the public transport system in the city, an entry-cost policy that encourages investment in the city and a restricting-migration policy that imposes some costs on migrants. We show that all these policies can increase urban employment but the transportation policy has much more drastic effects. This is because a decrease in commuting costs has both a direct positive effect on land rents, which discourages migrants to move to the city, and a direct negative effect on urban wages, which reduces job creation and thus migration. When these two effects are combined with search frictions, the interactions between the land and the labor markets have amplifying positive effects on urban employment. Thus, improving the transport infrastructure in cities can increase urban employment despite the induced migration from rural areas.     

Credit,vacancies and unemployment fluctuations

Propagation in equilibrium models of search unemployment is altered when vacancy costs require some external financing on frictional credit markets. The easing of financing constraints during an expansion as firms accumulate net worth reduces the opportunity cost for resources allocated to job creation. The dynamics of market tightness are affected by (i) a cost channel, increasing the incentive to recruit for a given benefit from a new hire, and (ii) a wage channel, whereby firms' improved bargaining position limits the upward pressure of market tightness on wages. Agency related credit frictions endogenously generate persistence in the dynamics of labor-market tightness, and have a moderate endogenous effect on amplification.     

Wage and price controls in the equilibrium sequential search model

In this paper, we study the effects of wage and price controls on employment, output, and welfare in a simplified version of the Bénabou (J. Econom. Theory 60 (1993) 140) equilibrium sequential search model with bilateral heterogeneity. We show that a price ceiling increases output but the change in welfare depends on three effects: the reduction in aggregate search costs, the increase in surplus due to increased output, and the transfer of production to the least efficient firm. The model is formally identical to a standard equilibrium search model of the labor market so analogous results hold for the minimum wage.