efficient search on the job and the business cycle the paper develops a model of directed search on the job in which transitions of workers between unemployment and employment and across employers are driven by heterogeneity in the quality of firm worker matches the equilibrium is such that the agents value and policy functions are independent of the endogenous distribution of workers across employment states hence the model can be solved outside of the steady state and used to measure the effect of cyclical productivity shocks on the labor market productivity shocks are found to generate large fluctuations in workers transitions unemployment and vacancies when matches are experience goods but not when matches are inspection goods

economic valuation of the threat posed by the establishment of the asian tiger mosquito in australia invasive species policy could be better informed if we understood how much people value reductions in the risks posed by these organisms this study investigates the public s willingness to pay wtp for additional measures to reduce the risk of invasion of the australian mainland by the asian tiger mosquito atm the study contributes to the literature by applying a stated preference method to estimate the public s wtp to reduce the risk of an atm invasion expressed as a change in probability it is the first ex ante invasive species analysis to test over two discrete invasion reduction probabilities based on management effort further to overcome the challenges in valuing changes in probabilities the study presented respondents with a well defined discrete difference in the final probability with one scenario reducing risk from 50 to 25 and the other from 50 to 5 we find a significant difference in the mean wtp values between these two scenarios a 67 vs a 90 the overall conclusion is that estimated benefits of reducing the probability of an atm incursion outweigh the costs

an adverse selection model of optimal unemployment insurance abstract we ask whether offering a menu of unemployment insurance contracts is welfare improving in a heterogeneous population we adopt a repeated moral hazard framework as in shavell and weiss 1979 supplemented by unobserved heterogeneity about agents job opportunities our main theoretical contribution is a quasi recursive formulation of our adverse selection problem including a geometric characterization of the state space our main economic result is that optimal contracts for bad searchers tend to be upward sloping due to an adverse selection effect this is in contrast to the well known optimal decreasing time profile of benefits in pure moral hazard environments that continue to be optimal for good searchers in our model

knowledge accumulation within an organization in this article we consider a knowledge accumulation problem within an organization that cannot prevent the worker from quitting and using the knowledge outside the organization we show that knowledge accumulation is delayed the fraction of working time allocated to knowledge creation is highest at the early career stage falls gradually then rises again before falling finally toward zero we determine the effect of a change in the severity of the enforcement problem or the specificity of knowledge we also discuss the form of the optimal life cycle wage profiles the role of the initial knowledge level and the role of discounting

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 abstract from author

the value of nonindigenous species risk assessment in international trade abstract managing the introduction of nonindigenous species is becoming a major goal of policy makers at regional national and international scales here we investigate at the national level the ideal design and expected net benefits of a risk assessment program for evaluating the desirability of nonindigenous species imports we show how to enhance the statistical rigor of such a system by correcting a common non random sampling problem encountered in the data this correction enables model output to be interpreted in an economically relevant way and facilitates a theoretically rigorous characterization of the balance between trade and nonindigenous species establishment risk using reptiles and amphibians imported to the u s as a case study we characterize economic outcomes over a range of cases and demonstrate substantial expected returns to such a screening program relative to the current effectively open door policy our results are informative for the current debate in the u s about whether to require federal agencies to apply risk assessment before allowing a species for import the framework presented decomposes a complex argument about risk management into component economic and statistical parts allowing for debate and improved understanding over each element to inform the overall program in a transparent fashion

cycles in natural resource commodity prices an analysis of the frequency domain abstract a model is derived that relates price cycles to investment behavior in the mineral industries and predicts that these cycles will be roughly twice as long as the investment period the period between the investment decision and the project completion spectral techniques are used to estimate the principal cycles in metal and fuel prices for the metals the estimated cycle lengths reinforce the model predictions however no significant cycles are found in the prices of the fuels the lead lag relationships between prices of different commodities are also investigated and are found to be significant for those that are jointly produced

breakthroughs deadlines and self reported progress contracting for multistage projects we study the optimal incentive schemes for multistage projects staged financing pervasive in both venture capital and research grants arises as a feature of the optimal contract the nature of progress plays an important role when progress is tangible incentives are provided through a series of deadlines and a reward scheme that decreases over time early progress in one stage gives the agent more time and funding to complete the next one when progress is intangible unverifiable progress reports are used despite the fact that the information in the report has no social value the optimal contract involves a soft deadline wherein the principal guarantees funding up to a certain date if the agent reports progress at that date then the principal gives him a relatively short deadline to complete the project if not then a probationary phase begins in which the project is terminated at a constant rate until progress is reported we explore the implications for welfare and optimal project design

the econometrics of damage control why specification matters the contribution of damage control agents to production differs fundamentally from that of standard inputs lands labor capital this paper develops an econometric model based on the key characteristics of damage control agents and examines its properties it demonstrates that standard production function specifications overestimate damage control agent productivity and have erroneous implications for the evolution of damage control agent productivity and use in response to changing environments e g the spread of pest resistance it also proposes several alternative specifications and discusses methods for estimating them

the control of invasive species on private property with neighbor to neighbor spillovers invasive pests cross property boundaries property managers may have private incentives to control invasive species despite not having sufficient incentive to fully internalize the external costs of their role in spreading the invasion each property manager has a right to future use of his own property but his property may abut others properties enabling spread of an invasive species the incentives for a foresighted property manager to control invasive species have received little attention we consider the efforts of a foresighted property manager who has rights to future use of a property and has the ability to engage in repeated discrete control activities we find that higher rates of dispersal associated with proximity to neighboring properties reduce the private incentives for control controlling species at one location provides incentives to control at a neighboring location control at neighboring locations are strategic complements and coupled with spatial heterogeneity lead to a weaker link public good problem in which each property owner is unable to fully appropriate the benefits of his own control activity future use rights and private costs suggest that there is scope for a series of coase like exchanges to internalize much of the costs associated with species invasion pigouvian taxes on invasive species potentially have qualitatively perverse behavioral effects a tax with a strong income effect e g failure of effective revenue recycling can reduce the value of property assets and diminish the incentive to manage insects on one s own property

resource price dynamics with non malleable extraction capital abstract non renewable resource extraction is nearly always capital intensive and extraction capital tends to be non malleable in thispaper we present and discuss a dynamic discrete time model of resource extraction embodying non malleable capital which can generate highly diverse patterns of price behaviour

inducing environmental disclosures a dynamic mechanism design approach this paper studies the design of voluntary disclosure regulations for a firm that faces a stochastic environmental hazard the occurrence of such a hazard is known only to the firm the regulator if finding a hazard collects a fine and mandates the firm to perform costly remediation that reduces the environmental damage the regulator may inspect the firm at any time to uncover the hazard however because inspections are costly the regulator also offers a reward to the firm for voluntarily disclosing the hazard the reward corresponds to either a subsidy or a reduced fine depending on whether it is positive or negative thus the regulator needs to dynamically determine the reward and inspection policy that minimizes expected societal cost in the long run we model this problem as a dynamic adverse selection problem with costly state verification in continuous time despite the complexity and generality of this setup we show that the optimal regulation policy follows a very simple cyclic structure which we fully characterize in closed form specifically the regulator runs scheduled inspections periodically after each inspection the reward level decreases over time until a subsequent inspection takes place if a hazard is not revealed the reward level is reset to a high level restarting the cycle in contrast to the reward level the mandated remediation level is constant over time nonetheless when subsidies are not allowed in the industry we show that the regulator should dynamically adjust this remediation level which then acts as a substitute for a subsidy our analysis further reveals that optimal inspection frequency increases not only when the inspection accuracy decreases but also when the penalty for not disclosing the hazard increases

labor market matching with precautionary savings and aggregate fluctuations we analyze a bewley huggett aiyagari incomplete markets model with labor market frictions consumers are subject to idiosyncratic employment shocks against which they cannot insure directly the labor market has a diamond mortensen pissarides structure firms enter by posting vacancies and match with workers bilaterally with match probabilities given by an aggregate matching function wages are determined through nash bargaining we also consider aggregate productivity shocks and a complete set of contingent claims conditional on this risk we use the model to evaluate a tax financed unemployment insurance scheme higher insurance is beneficial for consumption smoothing but because it raises workers outside option value it discourages firm entry we find that the latter effect is more potent for welfare outcomes we tabulate the effects quantitatively for different kinds of consumers we also demonstrate that productivity changes in the model in steady state as well as stochastic ones generate rather limited unemployment effects unless workers are close to indifferent between working and not working thus recent findings are corroborated in our more general setting

cash on hand and competing models of intertemporal behavior new evidence from the labor market this paper presents new tests of the permanent income hypothesis and other widely used models of household behavior using data from the labor market we estimate the excess sensitivity of job search behavior to cash on hand using sharp discontinuities in eligibility for severance pay and extended unemployment insurance ui benefits in austria analyzing data for over one half million job losers we obtain three empirical results 1 a lump sum severance payment equal to two months of earnings reduces the job finding rate by 8 12 on average 2 an extension of the potential duration of ui benefits from 20 weeks to 30 weeks similarly lowers job finding rates in the first 20 weeks of search by 5 9 and 3 increases in the duration of search induced by the two programs have little or no effect on subsequent job match quality using a search theoretic model we show that estimates of the relative effect of severance pay and extended benefits can be used to calibrate and test a wide set of intertemporal models our estimates of this ratio are inconsistent with the predictions of a simple permanent income model as well as naive rule of thumb behavior the representative job searcher in our data is 70 of the way between the permanent income benchmark and credit constrained behavior in terms of sensitivity to cash on hand

productivity gains from unemployment insurance this paper argues that unemployment insurance increases labor productivity by encouraging workers to seek higher productivity jobs and by encouraging rms to create those jobs we use a quantitative model to investigate whether this eect is comparable in magnitude to the standard moral hazard eects of unemployment insurance our model economy captures the behavior of the u s labor market for high school graduates quite well with unemployment insurance more generous than the current u s level unemployment would increase by a magnitude similar to the micro estimates but because the composition of jobs also changes total output and welfare would increase as well

does reducing unemployment insurance generosity reduce job match quality abstract this paper analyzes how a change in slovenia s unemployment insurance law affected the quality of jobs workers found after periods of unemployment taking advantage the natural experiment we show through difference in differences estimation results that reducing the potential duration of unemployment benefits had no detectable effect on wages on the probability of securing a permanent rather than a temporary job or on the duration of the post unemployment job

markov perfect risk sharing moral hazard and limited commitment abstract we define characterize and compute markov perfect risk sharing contracts in a dynamic stochastic economy with endogenous asset accumulation and simultaneous limited commitment and moral hazard frictions we prove that markov perfect insurance contracts preserve standard properties of optimal insurance with private information and are not more restrictive than a long term contract with one sided commitment markov perfect contracts imply a determinate asset time path and a non degenerate long run stationary wealth distribution quantitatively we show that markov perfect risk sharing contracts provide sizably more consumption smoothing relative to self insurance and that the welfare gains from resolving the commitment friction are larger than the gains from resolving the moral hazard friction at low asset levels while the opposite holds for high asset levels

the interaction of implicit and explicit contracts in repeated agency abstract in a repeated principal agent model in which the agent s actions are observable to the principal but not verifiable in court the agent s incentives derive both from salary payments based on verifiable signals and from implicit promises by the principal of bonuses for good behavior explicit short term contracts are designed to enhance the effectiveness of the infinite horizon implicit contract between principal and agent in a constrained efficient equilibrium bonuses smooth the consumption path of the risk averse agent by moving in the opposite direction from salaries total consumption and expected discounted utility for the rest of the game journal of economic literature classification numbers c7 c73 d8

credible monetary policy in an infinite horizon model recursive approaches abstract this paper develops recursive methods to study optimal and time consistent policy in dynamic models we analyze a version of calvo s 1978 monetary model and show that its time consistent outcomes can be completely characterized as the largest fixed point of either of two operators recursive application of these operators provides a computing algorithm which always converges to the set of time consistent outcomes finally we obtain valuable information about the nature of time consistent outcomes it is discovered in particular that all such outcomes are markovian the methods obtained are intuitive and should be useful for many applications journal of economic literatureclassification numbers e61 e52 c61

repeated insurance relationships in a costly state verification model with an application to deposit insurance abstract we consider the problem of an insurer who enters into a repeated relationship with a set of risk averse agents in the presence of ex post verification costs the insurer wishes to minimize the expected cost of providing these agents a certain expected utility level we characterize the optimal contract between the insurer and the insured agents we then apply the analysis to the provision of deposit insurance our results suggest in a deposit insurance context that it may be optimal to utilize the discount window early on and to make deposit insurance payments only later or not at all

moral hazard and secured lending in an infinitely repeated credit market game we analyze repeated moral hazard with discounting in a competitive credit market with risk neutrality even without learning or risk aversion long term bank borrower relationships are welfare enhancing the main result is that the borrower obtains an infinite sequence of unsecured loans at below spot market cost following the first good project realization this contract produces first best action choices prior to this stage the borrower gets secured loans with above market borrowing cost the optimal contract thus displays a selective memory feature taking only one of two forms at any given point in time depending on prior history we consider an infinitely repeated bank borrower relationship with moral hazard and universal risk neutrality and explore the ramifications of credit contract duration when the two well known benefits of long term contracting learning and improved risk sharing are absent our objectives are twofold the first is to analyze an infinitely repeated game with discounting in a credit market context we thus relate the theory of repeated games to financial intermediation theory particularly to issues of moral hazard and collateral related distortions the second objective is to understand noteworthy stylized facts of credit markets such as durability in credit relationships lower borrowing costs for established borrowers and unsecured loans for established borrowers versus secured loans for newer borrowers while these practices may be partly due to learning we show that learning is not essential to rationalize them even if information decays rapidly and banks learn nothing about borrowers through time these aspects of credit contracting arise in a repeated game context our main results are as follows first despite universal risk neutrality and the absence of learning a durable bank relationship benefits the borrower 2 the intuition is that the long term contracting permitted by a durable relationship enables the bank to efficiently tax and subsidize the borrower through time to reduce the use of costly collateral second the average welfare loss due to moral hazard per period is positive even as the time horizon goes to infinity third the optimal infinite horizon contract has the striking property that following the period

repeated moral hazard with a time inconsistent agent abstract i consider a repeated principal agent model with moral hazard in which the agent has preferences which are widely used to capture time inconsistency i analyze the case where the agent is sophisticated in the sense that he is fully aware of his inconsistent discounting i characterize the optimal wage scheme for such an agent and compare it to time consistent benchmarks the marginal cost of rewarding the agent for high output today exceeds the marginal benefit of delaying these rewards until tomorrow in this sense the principal does not smooth the agent s rewards over time when facing a sophisticated agent it is optimal for the principal to reward the good performance more and punish the bad performance more in the early period relative to the optimal wage scheme for a time consistent agent

unemployment insurance and job durations seasonal and non seasonal jobs the authors use regional and individual variation in unemployment insurance ui parameters to estimate the impact of ui incentives on job durations in doing so they distinguish between seasonal and nonseasonal jobs the authors find evidence of substantial tailoring of job durations to ui incentives in seasonal but not in nonseasonal jobs even for seasonal jobs adjusting ui parameters has small impacts on average job duration except in high unemployment regions increasing the ui entrance requirement leads to some job lengthening but also to the creation of more very short jobs

concepts and measures of natural resource scarcity with a summary of recent trends a general model of resource scarcity is presented from which previous models can be derived as special cases previous models of scarcity are compared and contrasted refining the concept of scarcity and leading to a resolution of current disputes over the appropriate measure of scarcity an update of the original work done by barnett and morse is summarized leading to reconsideration of their original conclusions it is found that energy and forest products experienced increasing scarcity during the 1970s

growth and risk sharing with private information abstract we examine the impact of incomplete risk sharing on growth and welfare the source of market incompleteness in our economy is private information a household s idiosyncratic productivity shock is not observable by others risk sharing between households occurs through long term contracts with intermediaries we find that incomplete risk sharing tends to reduce the rate of growth relative to the complete risk sharing benchmark numerical examples indicate that the welfare cost and the growth effect of private information are small

characterization of a risk sharing contract with one sided commitment in this paper i provide a stopping time based solution to a long term contracting problem between a risk neutral principal and a risk averse agent the agent faces a stochastic income stream and cannot commit to the long term contracting relationship to compute the optimal contract i also design an algorithm that is more efficient than value function iteration

optimal mortgage design this article studies optimal mortgage design in a continuous time setting with volatile and privately observable income costly foreclosure and a stochastic market interest rate we show that the features of the optimal mortgage are consistent with an option adjustable rate mortgage option arm under the optimal contract the borrower is given discretion of how much to repay until his balance reaches a certain limit the default rates and interest rate payment on the mortgage correlate positively with the market interest rate gains from using the optimal contract relative to simpler mortgages are the biggest for those who face more income variability buy pricey houses given their income level or make little or no down payment our model thus may help to explain a high concentration of option arms among riskier borrowers jel g20 g21 g33

optimal unemployment insurance with human capital depreciation and duration dependence this paper studies the effect of human capital depreciation and duration dependence on the design of an optimal unemployment insurance ui scheme our results partially confirm those obtained in most previous studies benefits should decrease with unemployment duration the optimal program also generates two main novel features which are not present in stationary models first if human capital depreciates rapidly enough during unemployment ui transfers are bounded below by a minimal assistance level that arises endogenously in the efficient program second we study the optimality of imposing a history contingent wage tax after reemployment our numerical simulations based on the spanish and us economies show that the wage tax should decrease with the length of worker s previous unemployment spell and become a wage subsidy for long term unemployed workers as a by product of our study we develop a systematic approach suitable for studying recursively a wide range of dynamic moral hazard problems and other models with similar characteristics

the adverse effect of unemployment insurance on workers on the job effort and labor market outcomes i investigate the effect of unemployment insurance on worker on the job effort and its macroeconomic impacts the results show that a moderate increase in unemployment benefits decreases the average wage and employment duration and aggregate output and increases average layoff rate

efficient propagation of shocks and the optimal return on money abstract we study optimal allocations in an environment in which money is essential due to lack of commitment and anonymity of individuals because the economy features aggregate preference shocks we apply a notion of implementability that allows for allocations with non trivial business cycle dynamics for the propagation of shocks we show that history dependence is predicted by the theory of second best and becomes necessary for optimality when the degree of patience is neither too low nor too high our analysis concludes with a discussion of whether there is a role for the propagation of shocks in alternative economic environments

large risks limited liability and dynamic moral hazard we study a continuous time principal agent model in which a risk neutral agent with limited liability must exert unobservable effort to reduce the likelihood of large but relatively infrequent losses firm size can be decreased at no cost or increased subject to adjustment costs in the optimal contract investment takes place only if a long enough period of time elapses with no losses occurring then if good performance continues the agent is paid as soon as a loss occurs payments to the agent are suspended and so is investment if further losses occur accumulated bad performance leads to downsizing we derive explicit formulae for the dynamics of firm size and its asymptotic growth rate and we provide conditions under which firm size eventually goes to zero or grows without bounds

moral hazard optimal unemployment insurance and experience rating abstract this paper is concerned with evaluating alternative unemployment insurance ui schemes in a dynamic economy with moral hazard we consider changes in the size and duration of ui benefits and the effects of experience rating and use a dynamic contracting approach to determine a benchmark optimal allocation radical changes in the current ui system increase welfare but not by much a move to full experience rating has distributional effects but the aggregate effects are negligible

choosing between adaptation and prevention with an increasing probability of a pandemic abstract the risk of pandemics is increasing driven by changes in human behavior and climate both of which are difficult for policymakers to control there are two main strategies available for reacting to these changes this paper considers the decision to invest in either adaptation domestic capital or prevention foreign capital before a pandemic in an interval of time when pandemic risk is increasing this paper demonstrates how relatively small investments in the two strategies can provide large savings through smaller expected future damages the technical relationships between adaptation prevention and risk also determine the optimal mixture of investment over time as risk increases the technical relationships between these three stocks causes the optimal mixture of strategies to change over time

unemployment insurance and job duration in canada we use data from the canadian 2 year longitudinal labour market activity survey of 1986 87 to estimate the effect of the unemployment insurance ui system on job duration particular attention is focused on the entrance requirements of the ui system which relate eligibility for ui benefits to an individual s recent employment history the article makes operational the ui entrance requirement provisions which take into account variations in the regional unemployment rate controlling for many personal and job characteristics we find evidence that a significant number of jobs terminate when they have reached the duration that would permit a ui claim

a quantitative analysis of unemployment benefit extensions abstract extensions of unemployment insurance ui benefits have been implemented in response to the great recession this paper measures the effect of these extensions on the unemployment rate using a calibrated structural model featuring job search and consumption saving decisions skill depreciation and ui eligibility the ongoing ui benefit extensions are found to have raised the unemployment rate by 1 4 percentage points which is about 30 of the observed increase since 2007 moreover the contribution of the ui benefit extensions to the elevated unemployment rate increased during 2009 2011 while the number of vacancies recovered the successive extensions kept search intensity down

optimal cartel equilibria with imperfect monitoring abstract there exist optimal symmetric equilibria in the green porter model 4 8 having an elementary intertemporal structure such an equilibrium is described entirely by two subsets of price space and two quantities the only production levels used by firms in any contingency the central technique employed in the analysis is the reduction of the repeated game to a family of static games

the equivalence of lending equilibria and signalling based insurance under asymmetric information i present a model in which a continuum of individuals have stochastic idiosyncratic income shocks complete insurance is physically feasible but unattainable due to an information asymmetry income shocks are observable only by the individuals receiving them any insurance institution must therefore rely on self reporting of income innovations two ways of achieving incentive compatible self reporting are presented the first is a debt market with an explicit lending restriction the second is an insurance contract that linearly filters a signal transmitted by individuals the two are then demonstrated to be identical equilibrium consumption fluctuates in a random walk which is inefficient given the physical potential for complete insurance but is efficient given the information constraints the results are complementary to those of green 1987 but permit more general stochastic processes of income to be analyzed serial correlation of income reduces the efficiency of the insurance

take a risk preferring prevention over control of biological invaders abstract scientists have argued that invasive species can be managed most cost effectively with greater investments in prevention further under ideas like the precautionary principle it is reasonable to expect that a cautious manager would use more prevention relative to control because it keeps more invaders out yet this is not typically done in many cases private and public resources are invested primarily to control existing invaders rather than to prevent new invasions managers frequently wait until after invaders have arrived and then scramble to limit the damages we believe these paradoxical decisions can be understood by recognizing the link between typical human preferences for risk bearing and the technology of risk reduction we demonstrate quantitatively how managers perceived to be cautious or averse to risk tend to shy away from prevention relative to control this counterintuitive result arises because control is a safer choice than prevention because its productivity is relatively less risky it works to remove existing invaders from the system in contrast the productivity of prevention is more uncertain because prevention only reduces the chance of invasion it does not eliminate it and invasion may not occur even in the absence of prevention managers averse to risk will inherently avoid as much uncertainty as possible whether the source of uncertainty regards ecological outcomes or economic productivity implications for environmental decision making are clear in invasive species management if managers act as though they are risk averse their caution can backfire when it leads to more control rather than prevention the social consequences of this choice are a greater probability of future invasions and lower social welfare our results suggest that social welfare is highest when managers were willing to take a risk with prevention

a portfolio balancing approach to natural capital and liabilities managing livestock and wildlife diseases with cross species transmission researchers often refer to stocks of desirable natural resources as natural capital and stocks of undesirable species as natural liabilities the logical extension is that when these natural resources interact then the ecosystem is a collection or portfolio of natural capital and liabilities however natural capital and liabilities held in an ecosystem portfolio are more complex to manage than financial asset portfolios the key problem in a financial asset portfolio is adjusting the rates of return on assets for risk and correlation of risk in contrast the returns on natural assets and liabilities require many other adjustments arising from stock related returns and depreciation that endogenously depend on both stocks and controls including interactions among these variables this means ecosystem portfolio analysis extends beyond the consideration of uncertainty and involves understanding complex economic ecological tradeoffs even in a deterministic setting we use capital theory in the context of a deterministic bioeconomic model of valuable wildlife livestock and a pathogen that can be passed between them to develop a portfolio balancing approach to understanding the tradeoffs associated with ecosystem management this specific ecosystem is highly relevant to conservation health and livestock agriculture within the context of this example we also explore issues of mitigation and adaptation to disease risks and the management implications of cross species transmission a final contribution is to examine how exports and infection risks influence the ecological thresholds that epidemiologists often focus on to guide disease management

optimal unemployment insurance this paper considers the design of an optimal unemployment insurance system the problem is modeled as a repeated principalagent problem involving a risk averse agent the unemployed worker and a risk neutral principal which cannot monitor the agent s search effort the optimal long term contract subject to the associated incentive constraints is characterized this contract involves a replacement ratio that decreases throughout the unemployment spell and a wage tax after reemployment that under some mild regularity conditions increases with the lenght of the unemployment spell some numerical results are presented that suggest that the gains from switching to this optimal unemployment insurance scheme could be quite large the performance of this optimal contract is also compared to alternative liquidity provision mechanisms

the cost of job loss this article identifies an equilibrium theory of wage formation and endogenous quit turnover in a labour market with on the job search where risk averse workers accumulate human capital through learning by doing and lose skills while unemployed optimal contracting implies the wage paid increases with experience and tenure indirect inference using german data determines the deep parameters of the model the estimated model not only reproduces the large and persistent fall in wages and earnings following job loss a new structural decomposition finds foregone human capital accumulation while unemployed is the worker s major cost of job loss

choice under uncertainty problems solved and unsolved ffifteen years ago the theory of choice under uncertainty could be considered one of the success stories of economic analysis it rested on solid axiomatic foundations it had seen important breakthroughs in the analytics of risk risk aversion and their applications to economic issues and it stood ready to provide the theoretical underpinnings for the newly emerging information revolution in economics 1 today choice under uncertainty is a field in flux the standard theory is being challenged on several grounds from both within and outside economics the nature of these challenges and of our profession s responses to them is the topic of this paper

optimal long term financial contracting we develop an agency model of financial contracting we derive long term debt a line of credit and equity as optimal securities capturing the debt coupon and maturity the interest rate and limits on the credit line inside versus outside equity dividend policy and capital structure dynamics the optimal debt equity ratio is history dependent but debt and credit line terms are independent of the amount financed and in some cases the severity of the agency problem in our model the agent can divert cash flows we also consider settings in which the agent undertakes hidden effort or can control cash flow risk

trends in natural resource commodity prices an analysis of the time domain abstract this paper attempts to reconcile the theoretical predictions of increasing real prices for nonrenewable natural resource commodities obtained from hotelling style models with the empirical findings of falling prices for these commodities a theoretical model for relative price movements is derived for the case of exogenous technical change and endogenous change in the grade of ores mined the model suggests a u shaped time path for relative prices the implied price movements are tested for all the major metals and fuels and the model parameters are found to be statistically significant for 11 out of the 12 commodities tested

making do with less working harder during recessions why did productivity rise during recent recessions one possibility is that average worker quality increased a second is that each incumbent worker produced more the second effect is termed making do with less using data from 2006 to 2010 on individual worker productivity from a large firm these effects can be measured and separated for this firm most of the gain in productivity during the recession was a result of increased effort additionally the increase in effort is correlated with the increase in the local unemployment rate presumably reflecting the costs of losing a job

optimal lending contracts and firm dynamics we develop a general model of lending in the presence of endogenous borrowing constraints borrowing constraints arise because borrowers face limited liability and debt repayment cannot be perfectly enforced in the model the dynamics of debt are closely linked with the dynamics of borrowing constraints in fact borrowing constraints must satisfy a dynamic consistency requirement the value of outstanding debt restricts current access to short term capital but is itself determined by future access to credit this dynamic consistency is not guaranteed in models of exogenous borrowing constraints where the ability to raise short term capital is limited by some prespecified function of debt we characterize the optimal default free contract which minimizes borrowing constraints at all histories and derive implications for firm growth survival leverage and debt maturity the model is qualitatively consistent with stylized facts on the growth and survival of firms comparative statics with respect to technology and default constraints are derived borrowing constraints are an important determinant of firm growth and survival 1 such constraints may arise in connection to the financing of investment opportunities faced by firms or temporary liquidity needs such as those required to survive a recession this paper develops a theory of endogenous borrowing constraints and studies its implications for firm dynamics in our model debt is constrained by the firm s limited liability and option to default a lending contract specifies an initial loan size future financing and a repayment schedule the choice of these variables in turn determines future growth the firm s future borrowing capacity and its ability and willingness to repay hence borrowing constraints and firm dynamics are jointly determined we study this dynamic design problem our model builds on thomas and worral s 1994 model of foreign direct investment at time zero a risk neutral borrower firm or entrepreneur has a project which requires a fixed initial set up cost every period the project yields revenues that increase with the amount of 1 there is considerable evidence suggesting that financing constraints are important determinants of firm dynamics gertler and gilchrist 1994 argue that liquidity constraints may explain why small manufacturing firms respond more to a tightening of monetary policy than do larger manufacturing firms perez quiros and timmermann 2000 show that in recessions smaller firms are more sensitive to the worsening of credit market conditions as measured by higher interest rates and default premia evans and jovanovic 1989 show that the liquidity constraints are essential in the decision to become an entrepreneur fazzari hubbard and petersen 1988 among others view financial constraints as an explanation for the dynamic behaviour of aggregate investment and cabral and mata 1996 are able to fit reasonably well the size distribution of portuguese manufacturing firms by estimating a simple model of financing constraints for surveys see hubbard 1998 and stein 2003

outside opportunities and termination abstract we study a dynamic principal agent relationship where a stochastic outside opportunity offer arises each period for the risk averse agent termination is costly but it allows the agent to pursue the available outside opportunity and the principal to return to an external market to hire a new agent the principal acts strategically with respect to the agent s outside offers and we show that it is optimal to terminate the current relationship if and only if the agent s outside offer is above a cutoff level the optimal contract generates both voluntary and involuntary terminations severance compensation arises endogenously and we show that it may be paid only in involuntary terminations conditional on termination the size of the optimal severance compensation depends positively on the agent s current compensation but negatively on his outside offer the optimal contract dictates an inverted u relationship between compensation and the probability of termination

mortal managers and long term goals an impossibility result this article examines decision myopia under effort and risk neutrality an infinite non overlapping sequence of mortal managers is selected and their performance evaluated contracts admit premature termination plant condition depends on maintenance which induces an interstage linkage in production when ability and action are imprecisely known by employers no contract achieves the first best outcome furthermore if the manager discounts less than the owners inefficiency is partially due to moral hazard which resembles myopia optimal contracts infer ability and motivate behavior via manipulation of wage schedules and tenure guidelines

intertemporal distortions in the second best we consider a very general class of public nance problems that encompasses ramsey models of optimal taxation as well as economies with limited commitment private information and political economy frictions we identify a su cient condition to rule out permanent intertemporal distortions at the optimum if there exists an admissible allocation that converges to the rst best steady state then all intertemporal distortions are temporary in the second best we analyze a series of applications to illustrate the signi cance of this result

efficient unemployment insurance this paper constructs a tractable general equilibrium model of search with risk aversion an increase in risk aversion reduces wages unemployment and investment unemployment insurance has the opposite effect insured workers seek high wage jobs with high unemployment risk an economy with risk neutral workers achieves maximal output without any unemployment insurance but an economy with risk averse workers requires a positive level of unemployment insurance to maximize output therefore moderate unemployment insurance not only improves risk sharing but also increases output

a test of the hotelling valuation principle time series tests of the hotelling r percent rule for natural resource prices have not been strongly supportive but the tests and the data are subject to serious difficulties we propose here an alternative testing strategy based on another but less widely known implication of the hotelling model we test this implication which we call the hotelling valuation principle by regressing the market values of the reserves of a sample of u s domestic oiland gas producing companies on their estimated hotelling values we find that the estimated hotelling values account for a significant portion of the observed variations in market values and that the hotelling measures are better indicators of the market values of petroleum properties than two widely cited publicly available alternative appraisals

repeated insurance contracts and moral hazard abstract an attempt is made to account for the frequently observed phenomenon of insurance companies offering discounts to clients who possess a favorable record of past claims we argue that such discounts provide a mechanism which enables both insurer and insured to counteract the inefficiency which arises from moral hazard

competitive risk sharing contracts with one sided commitment this paper analyzes dynamic equilibrium risk sharing contracts between profit maximizing intermediaries and a large pool of ex ante identical agents that face idiosyncratic income uncertainty that makes them heterogeneous ex post in any given period after having observed her income the agent can walk away from the contract while the intermediary cannot i e there is one sided commitment we consider the extreme scenario that the agents face no costs to walking away and can sign up with any competing intermediary without any reputational losses we demonstrate that not only autarky but also partial and full insurance can obtain depending on the relative patience of agents and financial intermediaries insurance can be provided because in an equilibrium contract an up front payment effectively locks in the agent with an intermediary we then show that our contract economy is equivalent to a consumption savings economy with one period arrow securities and a short sale constraint similar to bulow and rogoff 1989 from this equivalence and our characterization of dynamic contracts it immediately follows that without cost of switching financial intermediaries debt contracts are not sustainable even though a risk allocation superior to autarky can be achieved

on repeated moral hazard with discounting in this paper we analyze optimal contracts in an infinitely repeated agency model in which both the principal and agent discount the future we show that there is a stationary representation of the optimal contract when the agent s conditional discounted expected utility is used as a state variable this representation reduces the multi period problem to a static variational problem which can be analyzed using standard variational techniques this reduction is used to obtain several properties of the contract

economic incentives for managing filterable biological pollution risks from trade infectious livestock disease problems are biological pollution problems prior work on biological pollution problems generally examines the efficient allocation of prevention and control efforts but does not identify the specific externalities underpinning the design of efficiency enhancing policy instruments prior analyses also focus on problems where those being damaged do not contribute to externalities we examine a problem where the initial biological introduction harms the importer and then others are harmed by spread from this importer here the externality is the spread of infection beyond the initial importer this externality is influenced by the importer s private risk management choices which provide impure public goods that reduce disease spillovers to others making disease spread a filterable externality we derive efficient policy incentives to internalize filterable disease externalities given uncertainties about introduction and spread we find efficiency requires incentivizing an importer s trade choices along with self protection and abatement efforts in contrast to prior work that targets trade alone perhaps surprisingly we find these incentives increase with importers private risk management incentives and with their ability to directly protect others in cases where importers can spread infection to each other we find filterable externalities may lead to multiple nash equilibria

on optimal unemployment compensation abstract the design of an optimal unemployment compensation scheme is analyzed using a dynamic principal agent relationship between a risk neutral planner the principal and risk averse workers the agents where the planner s inability to observe workers job search efforts creates a moral hazard problem to design an implementable scheme we require that each agent is guaranteed a minimum level of expected discounted utility regardless of his past history in contrast with previous studies we find that the optimal contract is quite close to actual unemployment compensation schemes both qualitatively and quantitatively

dynamic business share allocation in a supply chain with competing suppliers this paper studies a repeated game between a manufacturer and two competing suppliers with imperfect monitoring we present a principal agent model for managing long term supplier relationships using a unique form of measurement and incentive scheme we measure a supplier s overall performance with a rating equivalent to its continuation utility the expected total discounted utility of its future payoffs and incentivize supplier effort with larger allocations of future business we obtain the vector of the two suppliers ratings as the state of a markov decision process and we solve an infinite horizon contracting problem in which the manufacturer allocates business volume between the two suppliers and updates their ratings dynamically based on their current ratings and the current performance outcome our contributions are both theoretical and managerial we propose a repeated principal agent model with a novel incentive scheme to tackle a common but challenging incentive problem in a multiperiod s

getting it done dynamic incentives to complete a project a principal wants an agent to complete a project the agent undertakes unobservable effort which affects in each period the probability that the project is completed we characterize the contracts that the principal sets with and without commitment with full commitment the contract involves the agent s value and wage declining over time in order to give the agent incentives to exert effort the best sequentially rational equilibrium for the principal also involves the agent s wage declining over time while the worst sequentially rational equilibrium for the principal has a constant wage and is in fact the unique stationary equilibrium the best weakly renegotiation proof equilibrium for the principal is achieved by a constant wage that maximizes the principal s payoff conditional on wages being constant we compare these solutions to the efficient outcome