search unemployment and the production of jobs the authors investigate the performance of the economy when search is required to find employment and when the duration of unemployment varies across sectors they assume that in one sector factor markets are frictionless while in the other se ctor idle factors of production must actively search each other out i n order to produce they focus on how well the economy allocates work ers across sectors and the conditions under which the factor mix with in a sector is correct the authors demonstrate that in equilibrium t he search sector is too small and its factor intensity is too asymmet ric copyright 1987 by royal economic society

choosy search and the mismatch of talents this article proposes a multi sector matching model where workers have symmetric sector specific skills and the search market is segmented by sector workers choose the range of markets they are willing to participate in i identify a composition externality workers do not take into account the impact of their choice on sector specific mean productivity among the pools of job seekers consequently workers prospect too many market segments and there is room for public policy even when the so called hosios condition holds

taxation in a two sided search model abstract this paper analyzes the effects of wage and profit taxation in a simple search and bargaining model wage tax effects depend upon the level of unemployment benefits if unemployment benefits are less than search costs or if benefits are taxed as income then a wage tax decreases unemployment it also decreases the wage thereby overshifting the tax burden profit tax effects depend upon job entry in the short run with a fixed number of jobs filled jobs plus vacancies a profit tax decreases unemployment it also raises the wage again overshifting the tax in the long run the converse holds

unravelling of dynamic sorting we consider a two sided finite horizon search and matching model with heterogeneous types and complementarity between types the quality of the pool of potential partners deteriorates as agents who have found mutually agreeable matches exit the market when search is costless and all agents participate in each matching round the market performs a sorting function in that high types of agents have multiple chances to match with their peers however this sorting function is lost if agents incur an arbitrarily small cost in order to participate in each round with a sufficiently rich type space the market unravels as almost all agents rush to participate in the first round and match and exit with anyone they meet copyright 2005 wiley blackwell

matching workers and jobs cyclical fluctuations in match quality using national longitudinal survey of youth data on tenure and wages this article analyzes the extent to which the level of job mismatching varies over the business cycle and how it is dealt with by the labor market i find significant cyclical variation in job match quality and an internalization of the variation by the labor market through wages mismatching occurs more during recessions but is primarily captured in starting wages the evidence suggests the cyclical phenomenon is one of general mismatching rather than an increased number of stopgap jobs during recessions

learning by doing vs learning about match quality can we tell them apart understanding the accumulation of match specific capital is crucial in shedding light on the reasons for the prevalence of long term employ ment relationships and on the welfare consequences of turnover in the labor market one of the most important source of match specific capital is human capital acquired through match specific learning such learn ing can take on two distinct forms in the first case workers accumulate match specific human capital through learning by doing in the second case a worker and a firm in an employment relationship learn about the quality of the match over time thereby acquiring valuable information i construct a structural model that embeds these two learning explana tions i show that it is possible to distinguish the two explanations given turnover data on employing firms coupled with data on workers such data now exist in the form of matched employer employee data sets i use a matched french data set to estimate the structural model using the efficient method of moments a simulation based estimation method i find that while learning by doing could be present in the first few months of an employment relationship learning about match quality dominates at tenures above half a year this finding has important consequences for economists understanding of the sources of match specific capital and for the desirability of policies that alter the incentives for turnover for workers of different tenure

profit efficiency for spanish savings banks abstract frontier profit efficiency is examined for spanish savings banks over 1986 1991 a period in which the spanish banking has seen considerable deregulation in spain the standard assumption that firms operate in a perfectly competitive output market is unlikely to be met thus we use an alternative profit function specification which allows for market power in the output market profit efficiency is determined using the thick frontier approach and estimated using both alternative and standard profit function specifications to illustrate the effect of different assumptions regarding the competitiveness of the output market estimation of the alternative profit function suggests that the profit inefficiency of spanish savings banks which averaged 28 fell by forty percent between 1986 to 1991 the standard profit function which we believe yields less reliable results generated greater average inefficiency there was no significant shift up or down in the profit frontier itself

robust comparative statics in large dynamic economies we consider infinite horizon economies populated by a continuum of agents subject to idiosyncratic shocks this framework contains models of saving and capital accumulation with incomplete markets in the spirit of works by bewley aiyagari and huggett models of entry exit and industry dynamics in the spirit of hopenhayn s work and dynamic models of occupational choice and search models as special cases robust and easy to apply comparative statics results are established with respect to exogenous parameters as well as various kinds of changes in the markov processes governing the law of motion of the idiosyncratic shocks

regional effects of exchange rate fluctuations we exploit differences across u s states exposure to trade to study the effects of changes in the exchange rate on economic activity across states trade weighted exchange rate depreciations are associated with increased state exports reduced state unemployment and higher state hours worked the effects are particularly strong during periods of economic slack a multiregion model with interstate trade and labor flows calibrated to match state level trade data and migration flows replicates the empirical relationship between exchange rates and unemployment the high degree of interstate trade plays an important role in transmitting shocks across states in the first year whereas interstate migration shapes cross sectional patterns in later years we use the model to study the regional effects of tariffs in the united states the model suggests that a 25 chinese import tariff on u s goods would be felt throughout the united states even in states with small direct linkages to china raising unemployment rates by 0 2 to 0 7 percentage points in the short run

frictional assignment i efficiency abstract this paper examines the two sided matching problem where the agents on each side of the market are heterogeneous and the matching process is time consuming this is cast in a labor market setting where workers of different skills match with different machine qualities i characterize the efficient allocation and then show that it can be decentralized by a market mechanism the efficient assignment is not always positively assortative despite the fact that machine qualities and skills are complementary in production to decentralize the efficient allocation the market mechanism requires the firms to post wages and commit each machine quality to a particular skill implications on wage inequality are briefly examined journal of economic literature classification numbers j31 e24 j64

environmental policy and the equilibrium rate of unemployment abstract this paper integrates environmental policy instruments with the theory of equilibrium unemployment we investigate the question of whether a low equilibrium rate of unemployment and a high quality of the environment are complementary policy goals or must be traded off it turns out that an interval exists for a tax on emissions where the two goals are indeed complementary the tax stimulates the emergence of an abatement sector which provides pollution control and vacancies for the job seekers for constrained efficiency the policy maker operates five instruments to internalize the environmental and the search externalities a tax on emissions employment subsidies and recruiting allowances for the polluting industries are sufficient to implement the first best the optimal emission tax is an increasing function of the workers bargaining strength for labor markets where workers have a strong bargaining position the optimal pollution tax may easily exceed the pigouvian tax

employment inequality why do the low skilled work less now abstract low skilled prime age men are less likely to be employed than high skilled prime age men and the differential has increased since the 1970s i build a search model encompassing three explanations 1 automation and trade reduced the demand for low skilled workers 2 health welfare and recreational gaming computer technology reduced the supply of low skilled workers and 3 factors affecting job search such as online job boards reduced frictions for high skilled workers i find a shift in demand away from low skilled workers was the leading cause a shift in supply had little effect and search frictions actually reduced employment inequality

r d in a model of search and growth just how important a determinant of economic growth is the efficacy with which markets are organized it is clear that in order to answer this question it is necessary to have both a well articulated theory of economic growth and a precise notion of what it means for one market to be better organized than another the newly developed theory of endogenous growth pioneered by among others paul m romer 1986 robert e lucas 1988 nancy stokey 1988 and gene grossman and elhanan helpman 1991 has equipped economists with a rigorous microeconomic foundation of the growth process since its original inception research in this area has bifurcated one strand of work has continued to emphasize the importance of capital accumulation both physical and human in environments in which agents are competitive price takers the other strand has a distinctly neo schumpeterian flavor in which firms are price setters and purposive innovative activity leads to technological advancement but what of the role played by market organization the growth literature has remained relatively silent on this issue the reason is that the canonical growth model is one in which trade either competitive or monopolisticly competitive is coordinated by the walrasian auctioneer given that ex hypothesi trade is frictionless it is meaningless to use this framework to discuss issues pertaining to improvements in market organization however beginning with the seminal contributions of peter diamond 1982 dale t mortensen 1982 and christopher pissarides 1985 economists have begun to construct models that dispense with the auctioneer s coordinating function in this setting it is possible to make precise the notion of an improvement in market efficacy since search and bargaining frictions are explicitly incorporated as an integral part of the trading environment yet it is only very recently that this literature has begun to explore the consequences for perpetual economic growth

should buyers or sellers organize trade in a frictional market to answer the question in the title this article characterizes the socially efficient organization of the market with search frictions the efficient organization depends on the relative elasticity in the supply between the two sides of the market the costs of participating in the market and organizing trade and the a symmetry in matching we also show that the social optimum can be implemented by a realistic market equilibrium where the organizers set up trading sites to direct the other side s search the results provide a unified explanation for why trade has often been organized by sellers in the goods market by buyers firms in the labor market and by both sides in the asset market the analysis also sheds light on how the efficient market organization can change with innovations such as e commerce and just in time production

decentralized international exchange traditional models of international trade take place within trading environments in which trade is coordinated by a walrasian auctioneer who instantly matches buyers and sellers in world markets this assertion seems inconsistent with evidence suggesting that trading arrangements seem to economize on transactions costs associated with international trade recognizing these insights we depart from standard models of international trade by incorporating the difficulties in the coordination of exchange within a two country random matching model of international trade we capture a motivation for trade through comparative advantage and interpret trade across economies to be associated with an agent s endogenous choice to participate in foreign markets although an individual may decide to search abroad to obtain additional gains from trade resulting from comparative advantage she is less likely to meet trading partners abroad as search frictions are higher in the foreign country than in the domestic market using this framework we show that international trade is associated with convergence in relative prices across countries we also show that the extent of market frictions in the foreign country affects relative prices the volume of international trade and welfare levels due to market participation externalities associated with international trade we show that a movement from autarky to free trade may actually lower welfare levels we conclude by examining the possible inefficiencies associated with international trade due to the decentralized nature of exchange and the policy implications of our model

long term partnership formation marriage and employment of course marriage and employment are different nevertheless a worker looking for a job a rm looking for worker or a single person looking for a marriage partner face similar problems as all are seeking a long term partner indeed forming long term partnerships is a common occurrence in life there are many other examples business people search for other business people to form a pro table relationship bridge players seek to nd a suitable partners students search for a good university we would all like to nd a good friend etc the problem becomes signi cant if there are substantial differences in the return obtained from forming a partnership with different partners for example employers differ in the wages they offer or in the work environment they provide in such a situation a worker may reject some job offers similarly as many have learned to their cost some make better marriage partners than others the problem is two sided while a worker is evaluating a potential employer the employer is also evaluating the worker it is this two sided aspect of the problem that generates a signi cant interest a worker s willingness to accept employment at a rm depends not only on the characteristics of the rm but also the other possible options open to the worker the better an individual s opportunities elsewhere the more selective he or she will be in evaluating a potential partnership an academic who believes harvard may make an offer in the near future will be more selective in evaluating offers from lesser universities in this way expectations play a role if a single man believes that few if any women will nd him an acceptable marriage partner then he may accept the rst opportunity that presents itself partnership formation typically does not comply with a classic market situation where all participants know everything and all trades take place at zero cost finding a job nding a husband or wife or nding a business partner is a time consuming activity where opportunities typically arrive over time at uncertain intervals of time of course we can act in ways that in uence the arrival rate of potential partner workers go to employment agencies or read help wanted advertisements in newspapers singles of a certain age go to discos or join tennis clubs the literature on search and matching sm see mortensen 1982 and pissarides 1990 for early examples 1 provides an excellent framework for the economic journal 109 june f307 f334 royal economic society 1999 published by blackwell publishers 108 cowley road oxford ox4 1jf uk and 350 main street malden ma 02148 usa

wage differentials discrimination and efficiency abstract i analyze a large labor market where homogeneous firms post wages to direct the search of workers who differ in productivity i show that the model has a unique equilibrium the wage differential depends positively on the workers productivity differential only when the latter is large when the productivity differential is small high productivity workers get a lower wage than low productivity workers this reverse wage differential remains even when the productivity differential shrinks to zero however the equilibrium is socially efficient high productivity workers always get the employment priority and higher expected wages than low productivity workers although discrimination in terms of expected wages does not exist conventional measures are likely to incorrectly find discrimination in the model

communication about future policy rates in theory and practice a survey we discuss the theoretical rationale for central bank communication about future policy rates either as part of inflation targeting or in the form of forward guidance we also summarize both actual central bank communication about future policy rates and empirical evidence on the effectiveness of these types of communication we argue that there is a disconnect between the theory and practice of forward guidance as theory assumes commitment on the part of the central bank while in practice central banks generally do not commit future theoretical research on forward guidance should therefore take the absence of commitment by central banks into account

schumpeterian competition in experimental markets abstract we report on a series of laboratory experiments that capture key elements of research and development r d rivalry the experimental environment has a small number of sellers who compete in terms of pricing and production decisions and in terms of cost reducing r d rewards for innovation depend on the profitability of product market competition the experiments capture a kind of dynamic schumpeterian competition there is a sharp contrast in experimental results between monopolies and four seller competitive markets aggregate r d is higher under competition than under monopoly and prices follow marginal cost reductions much more quickly under competition than under monopoly the paper examines market performance in the experiments and the sources of market performance problems

employment efficiency and sticky wages evidence from flows in the labor market i consider three views of the labor market in the first wages are flexible and employment follows the principle of bilateral efficiency workers never lose their jobs because of sticky wages in the second wages are sticky and inefficient layoffs do occur in the third wages are also sticky but employment governance is efficient i show that the behavior of flows in the labor market strongly favors the third view in the modern u s economy recessions do not begin with a burst of layoffs unemployment rises because jobs are hard to find not because an unusual number of people are thrown into unemployment