ADVERSE SELECTION,LEARNING, AND COMPETITIVE SEARCH

I develop a model that allows for an analysis of the effects of time on adverse selection in the presence of search frictions. I find that, as a firm takes longer to adjust a worker's contract in response to learning about his type, inefficient overwork during the time before wage adjustment (probation) decreases. This provides a rationale for an optimal (minimum) probation period of about one month in the baseline scenario. Optimal probation duration varies with the degree of search frictions, the cost of effort, the relative productivity of different types of workers, and minimum wage regulations.     

Incentives,pay, and performance: a study of Australian employees

The paper analyses the determinants of self-reported work effort using a 1988 survery of Australian employees. While controlling for the endogeneity of the firm's choice of incentives and pay, it is found that direct incentive schemes have predicted effects, and the efficiency wage hypothesis is supported: pay and work effort are positively correlated. Two efficiency wage models are tested: Akerlof's gift exchange model, and work discipline arguments regarding monitoring difficulties and threats of dismissal. The latter argument is broadly consistent with the data.     

Towards a More Complete Efficiency Wage Theory

The efficiency wage is an important topic in the theory of employment. In a traditional efficiency wage model, only the representative firm is optimizing against an assumed S‐shaped effort supply function. This S‐shaped supply curve is critical for the model and the absence of a derivation of the curve in the literature means that it is an incomplete theory. In the present paper, we extend the model by specifying a worker's representative utility function so that the corresponding argmax function will be the S‐shaped effort supply curve. This will make the worker's decision process endogenous and will produce a more complete model. The importance of this extension is clear. The characterization of the utility function will make explicit the necessary conditions and crucial assumptions of the traditional model. More importantly, the extension will allow researchers to introduce employment compensation factors into the worker's utility function for analysis. This has important bearings on future development in employment theory. For example, a worker's satisfaction from shirking (net of dismissal risks), or his or her willingness to search for jobs (net of search cost), can now be included in his or her utility function to form an optimal work or search strategy. Incorporating the worker's optimization behaviour into the model will also enable researchers to study policy directed not just towards firms but also towards the worker's decision process. Furthermore, this approach provides a framework for researchers to generate comparative statics. These comparative statics can lead to interesting topics for econometric models or to further research within this field.     

Games of status and discriminatory contracts

Following recent empirical evidence which indicates the importance of rank for the determination of workers' wellbeing, this paper introduces status seeking preferences in the form of rank-dependent utility functions into a moral-hazard framework with one firm and multiple workers, but no correlation in production. We show that workers' concern for the rank of their wage in the firm's wage distribution induces the firm to offer discriminatory wage contracts when its aim is to induce all workers to expend effort.     

On the optimality of a minimum wage: New insights from optimal tax theory

We build a theoretical model to study whether a minimum wage can be welfare-improving if it is implemented in conjunction with an optimized nonlinear income tax. We consider this issue in a framework where search frictions on the labor market generate unemployment. Workers differ in productivity. The government does not observe workers' productivity but only their wages. Hence, the redistributive policy solves an adverse selection problem. We show that a minimum wage is optimal if the bargaining power of the workers is relatively low. However, if the government controls the bargaining power, then it is preferable to set a sufficiently high bargaining power.     

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.     

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.     

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.     

GENDER DISCRIMINATION ESTIMATION IN A SEARCH MODEL WITH MATCHING AND BARGAINING*

This article develops a search model of the labor market with matching, bargaining, and employers' taste discrimination in which—under necessary but standard distributional assumption—it is possible to separately identify gender discrimination and unobserved productivity differences. The equilibrium shows that both prejudiced and unprejudiced employers wage discriminate. Maximum likelihood estimates on CPS data indicate that half of the employers are prejudiced, average female productivity is 6.5% lower, and two‐third of the gender earning differential may be explained by prejudice. An affirmative action policy is implemented resulting in a redistribution of welfare from men to women at no cost for employers' welfare.     

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.     

The labor wedge as a matching friction

We use a search and matching model to decompose the labor wedge into three classes of labor market frictions and evaluate their role for the labor wedge and unemployment. We find that there is an asymmetric effect of labor market frictions on the labor wedge and unemployment. While the wedge is to a large extent explained by changes in matching efficiency, unemployment is accounted for by the combination of frictions to matching efficiency, job destruction and bargaining. If search and matching frictions give rise to the labor wedge, then it is relevant for explaining unemployment mainly through changes in matching efficiency.     

Holdup and wage dispersion

This paper provides a search-theoretic model of the labor market, in which large firms hire workers sequentially and wages are bargained with full commitment. The firm's optimal vacancy-posting strategy trades off the fact that a larger size decreases marginal benefits from subsequent jobs, but avoids higher future recruiting costs attributable to the holdup effect. The holdup effect is dominant if the production function is not sufficiently concave, resulting in firm-size wage premium. The equilibrium features wage dispersion both within and between firms. When calibrated to the U.S. data, the extended model accounts for 67%–84% of the observed wage dispersion, among which 13%–27% is attributed to the holdup effect.     

Efficiency of two sided investments in an equilibrium unemployment framework

This paper investigates the efficiency of investments by firms and workers in a matching model with high- and low-productivity jobs. Search is sector specific and random within sectors. Search frictions and ex-post bargaining imply that wage inequality arises as a result of the difference in investment costs between the sectors. The efficiency properties of the equilibrium are analyzed under the particular division in bargaining proposed by Hosios (1990). The conclusion is that the equilibrium is inefficient, with a too low fraction of workers and a too high vacancy-unemployment ratio in the high-productivity sector. The opposite happens in the low-productivity sector.     

Equilibrium Search with Continuous Productivity Dispersion: Theory and Nonparametric Estimation

In this article we develop an equilibrium search model with a continuous distribution of firm productivity types within a given labor market. We characterize equilibrium, derive expressions for the endogenous equilibrium wage distributions, and characterize the set of wage distributions that can be generated by the model. We develop a structural nonparametric estimation method for the productivity distribution. We estimate the model using French longitudinal survey data on labor supply, and we compare the results with those from a French panel data set of firms. The results are informative on the degree to which firms exploit search frictions.     

FiMod — A DSGE model for fiscal policy simulations

This paper develops a medium-scale dynamic, stochastic, general equilibrium (DSGE) model for fiscal policy simulations. Relative to existing models of this type, our model incorporates two important features. First, we consider a two-country monetary union structure, which makes it well suited to simulate fiscal measures by relatively large countries in a currency area. Second, we provide a notable degree of disaggregation on the government expenditures side, by explicitly distinguishing between (productivity-enhancing) public investment, public purchases and the public sector wage bill. In addition, we consider a labor market characterized by search and matching frictions, which allows to analyze the response of equilibrium unemployment to fiscal measures. In order to illustrate some of its applications, and motivated by recent policy debate in the Euro Area, we calibrate the model to Spain and the rest of the area and simulate a number of fiscal consolidation scenarios. We find that, in terms of output and employment losses, fiscal consolidation is the least damaging when achieved by reducing the public sector wage bill, whereas it is most damaging when carried out by cutting public investment.     

DYNAMIC CONTRACTS WITH WORKER MOBILITY VIA DIRECTED ON‐THE‐JOB SEARCH

This article proposes a model with dynamic incentive contracts and on‐the‐job search in a frictional labor market. The optimal long‐term contract exhibits an increasing wage–tenure profile. With increasing wages, worker effort also increases with tenure. These two features imply that the probabilities of both voluntary and involuntary job separation decrease with both job tenure and the duration of employment. Given these results, workers experience differing labor market transitions—between employment, unemployment, and across different employers—and the equilibrium generates endogenous heterogeneity among ex ante homogeneous workers.     

Job search and mobility in developing countries. Theory and policy implications

A labor market model is developed in which the formal sector is characterized by search frictions whereas the informal sector is competitive. We show that there exists a unique steady-state equilibrium in this dual economy. We then consider different policies financed by a tax on firms' profits. We find that reducing the unemployment benefit or the firms' entry cost in the formal sector induces higher job creation and formal employment, reduces the size of the informal sector but has an ambiguous effect on wages. We also find that an employment/wage subsidy policy and a hiring subsidy policy have different implications. In particular, the former increases the size of the informal sector while the latter decreases it.     

SKILL BIAS AND EMPLOYMENT FRICTIONS IN THE U.S. LABOR MARKET 1970–1990*

This article studies simultaneous changes in four labor market variables: the unemployment rates for college and high‐school graduates, the education wage premium, and the level of college participation. It develops an equilibrium search and matching model of the labor market where education is endogenously determined. Then the model is used to investigate quantitatively whether the change in the above labor market variables from 1970 to 1990 in the United States can be traced to changes in the environment. A skill‐biased change in technology together with an increase in employment frictions can explain much of the observed variation in these variables.     

Labor market frictions and the international propagation mechanism

The paper studies the role of labor market frictions in accounting for international business cycle comovement. To this aim, we embed labor market search and matching frictions in a two-country New Keynesian model. We show that labor market frictions amplify the international propagation of supply and demand shocks. In terms of cyclical properties then, they raise the cross-country output correlation. Adding labor market search in the New Keynesian model thus improves its ability to account for the business cycle comovement observed in G7 countries in the recent decades. Nominal wage rigidity substantially contributes to this result. Labor market institutions also play a role. Yet, their impact is not unequivocal depending on the institution considered. Business cycle synchronization is thus found to increase with the generosity of the unemployment benefits system, whereas it decreases with the strictness of employment protection.     

The political economy of public employment programs

What are the welfare implications of a political equilibrium where the choice of active labor market programs (ALMPs) have to please the employed majority? This issue is examined in an equilibrium model featuring matching frictions and worker–firm wage bargaining. It turns out that the welfare consequences depend on the nature of ALMPs and the political weight attributed to firm interests. If firm values carry little political weight and programs contribute to wage pressure, the employed will opt for excessive program activity.