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.     

Wage/tenure contracts with heterogeneous firms

This paper investigates equilibria where firms post wage/tenure contracts and risk averse workers search for new job opportunities whether employed or unemployed. We generalize previous work by assuming firms have different productivities. Equilibrium implies more productive firms always offer more desirable contracts. Thus workers never quit from more productive firms for less productive firms. Nevertheless turnover is inefficient as employees with long tenures at low productivity firms may reject outside job offers from more productive firms. A worker who quits to a more productive firm may accept a wage cut. Such wage cuts are compensated by faster “promotion” rates to higher wage levels in the future. We also generalize previous arguments by showing equilibria exist where the distribution of offers contains interior mass points and find equilibrium wage/tenure contracts need not be smooth.     

Search, money, and inflation under private information

I study monetary exchange and inflation when buyers have private information about their willingness to pay for certain goods. Introducing imperfect information in the Lagos-Wright [A unified framework for monetary theory and policy analysis, J. Polit. Economy 113(3) (2005) 463-484] economy shows that the existence of monetary equilibrium is a more robust feature of the environment. In general, my model has a monetary steady state in which only a proportion of the agents hold money. Agents who do not hold money cannot participate in trade in the decentralized market. The proportion of agents holding money is endogenous and depends (negatively) on the level of expected inflation. As in Lagos and Wright's model, in equilibrium there is a positive welfare cost of expected inflation, but the origins of this cost are very different.     

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.     

WHO SEARCHES?*

We consider a directed search model with buyers and sellers and determine whether buyers look for sellers or vice versa. The buyers and sellers can choose to search or wait; what they do in equilibrium depends on the relative size of the two populations and the price formation mechanism. We study bargaining and auctions and find that when one population is much larger than the other the former searches and the latter waits. Under auction with roughly equal populations some buyers and sellers search and some wait. Our results challenge the practice of postulating who searches and who waits.     

The Effectiveness of Indigenous Job Search Strategies

This analysis uses the only existing large-scale longitudinal survey of Indigenous Australians to examine the effects of job search behaviour over an 18-month period starting from March 1996. Job search methods were not generally related to the probability of finding and retaining employment when a range of other personal and regional factors are taken into account. Search intensity (as measured by the number of jobs applied for) had a significant effect on the prospect of finding employment, but was unrelated to the probability of job retention.     

Search by committee

We consider the problem of sequential search when the decision to stop is made by a committee and show that a unique symmetric stationary equilibrium exists given a log concave distribution of rewards. We compare search by committee to the corresponding single-agent problem and show that committee members are less picky and more conservative than the single agent. We show how (i) increasing committee size holding the plurality fraction constant and (ii) increasing the plurality rule affect the equilibrium acceptance threshold and expected search duration. Finally, we show that unanimity is optimal if committee members are sufficiently patient.     

Search and the market for ideas

We study a market where innovators, who are good at coming up with ideas, can sell them to entrepreneurs, who might be better at implementing them. The market is decentralized, with random matching and bargaining. Ideas are characterized by five salient features: they are indivisible; partially nonrival; intermediate inputs; subject to informational frictions; and difficult to collateralize. This last feature gives rise to a demand by entrepreneurs for liquidity. We determine which ideas get traded in equilibrium and compare this to the efficient outcome, emphasizing the impact of bargaining and liquidity considerations. Among other applications, we study how outcomes in the idea market affect the labor market.     

Introduction to Search Theory and Applications

This introduces the Symposium on Search Theory and Applications.     

Transfer fee regulations in European football

We analyze the impact of three different transfer fee systems on payoffs, contract lengths, training and effort incentives in European football. The different regimes, being used until 1995 (“pre-Bosman”), currently in use (“Bosman”), and recently approved (“Monti”) differ with respect to the transfer fee an initial club is entitled to depending on whether a player has a valid contract or not. We show that the different systems differ only with respect to the contract length if the contract which maximizes the expected joint surplus of the initial club and the player is feasible under each system. Otherwise, regime P is strictly dominated by regime B in terms of expected social welfare. Regime M leads to higher effort but lower incentives to invest in training compared to system B.     

Informational externalities with lump-sum sampling

Abstract .  We consider a game of strategic experimentation where agents are restricted to an all-or-nothing sampling strategy. The strategic interaction between agents due to informational externalities is affected by the sizes of the experimentation samples and the sensitivity of information to changes in sample sizes. There is experimentation only if the overall sample is large enough. Equilibrium may involve optimal, insufficient or excessive experimentation relative to a second-best welfare benchmark. This unusual over-experimentation result is associated not necessarily with large samples but with a low elasticity of the value of information with respect to the sample size.     

Search and Knightian uncertainty

Suppose that “uncertainty” about labor market conditions has increased. Does this change induce an unemployed worker to search longer, or shorter? This paper shows that the answer is drastically different depending on whether an increase in “uncertainty” is an increase in risk or that in true uncertainty in the sense of Frank Knight. We show in a general framework that, while an increase in risk (the mean-preserving spread of the wage distribution that the worker thinks she faces) increases the reservation wage, an increase in Knightian uncertainty (a decrease in her confidence about the wage distribution) reduces it.     

Search Theory: The 2010 Nobel Memorial Prize in Economic Sciences

This paper surveys search theory with an emphasis on the contributions of the 2010 laureates for the Nobel Memorial Prize in Economic Sciences, Peter Diamond, Dale Mortensen, and Christopher Pissarides.     

Economic integration and agglomeration in a middle product economy

We examine the interactions between economic integration and employment agglomeration in a neoclassical-growth, middle-product economy. There are two vertically integrated economies, with competitive final good firms operating plants in both regions and monopolistically-competitive intermediate good firms operating each in only one region. Immobile workers are employed with traded middle products to produce the nontraded final good; mobile workers are used with immobile capital to design and produce differentiated intermediate good inputs. While agglomeration and growth need not be positively related, trade need not enhance regional growth nor widen the skilled-unskilled wage gap.     

Benefit duration and unemployment entry: A quasi-experiment in Austria

Apart from being an important aspect of job-search behavior of individuals, potential benefit duration can also have effects on unemployment entry rates. In this paper, the causal connection between the two is investigated for the case of Austria, using a quasi-experimental situation that arose following the enactment of a law that extended benefit duration for older workers in specific regions of the country. Unemployment entry is found to have risen between 4 and 11 percentage points due to the new law. Several robustness checks are presented to see if a causal interpretation of this result is possible. Preliminary analysis shows that this increase in unemployment entry can be best understood not as voluntary quits but layoffs by firms who want to get rid of high-tenured and expensive older workers.     

Communication and reputation in procurement auctions — Some empirical evidence

This paper studies communication and reputation in market interactions using data from online procurement auctions. Positive reputation ratings and engaging in communication increase a bidder’s probability of winning. Messages are primarily used to reduce the asymmetric information associated with transactions.     

Sorting versus screening: Search frictions and competing mechanisms

In a market where sellers compete by posting trading mechanisms, we allow for a general search technology and show that its features crucially affect the equilibrium mechanism. Price posting prevails when meetings are rival, i.e., when a meeting by one buyer reduces another buyer's meeting probability. Under price posting buyers reveal their type by sorting ex-ante. Only if the meeting technology is sufficiently non-rival, price posting is not an equilibrium. Multiple buyer types then visit the same sellers who screen ex-post through auctions.     

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.     

Public goods in networks

This paper considers incentives to provide goods that are non-excludable along social or geographic links. We find, first, that networks can lead to specialization in public good provision. In every social network there is an equilibrium where some individuals contribute and others free ride. In many networks, this extreme is the only outcome. Second, specialization can benefit society as a whole. This outcome arises when contributors are linked, collectively, to many agents. Finally, a new link increases access to public goods, but reduces individual incentives to contribute. Hence, overall welfare can be higher when there are holes in a network.