modelling output growth a new approach abstract the paper proposes a new approach to modelling output growth and empirically compares the relative efficiency in terms of average mse of forecasts of alternative estimation and modelling methods applied to two well known multi equation macroeconomic models fitted to australian data for the period 1962 to 1987 the gain in relative efficiency from the new approach is found to be up to 129 percent over the ols or ml procedures

limited liability and incentive contracting with ex ante action choices abstract this article examines a principal agent model of financial contracting in which a risk neutral entrepreneur agent makes an unobservable ex ante effort choice while employing the investment funds of a risk neutral investor principal the key innovation is that the investment contract is subject to statutory liability limits given these liability limits two settings are considered one in which the investor payoff function is also constrained to be monotonically nondecreasing in firm profit and another in which no such monotonic contract constraint is imposed in the former case a standard debt contract is shown to emerge and a first best effort choice is not achieved in the latter setting the optimum is characterized by a live or die payoff function and a first best effort level may or may not be realized

multi period insurance contracts this paper examines the form of insurance contracts in the presence of asymmetric information about consumers accident probabilities our goal is to understand the adjustment in contract terms as a function of accident histories in a finite horizon model we also compare these adjustments between alternative market structures our principal findings indicate that history dependent insurance contracts serve a useful sorting role individuals who declare themselves low risks to insurance companies face adverse contracturai terms if they subsequently have many accidents these adjustments are strongest in the case of a single insurance seller but are present in the competitive model as well

on the mean variance tradeoff in option replication with transactions costs this paper analyzes the tradeoff between cost and risk of discretely rebalanced option hedges in the presence of transactions costs i present closed form solutions for expected hedging error transactions costs and variance of the cash flow from a time based hedging strategy similar to that analyzed by leland 1985 furthermore i characterize the cost and risk of a move based hedging strategy without resorting to monte carlo simulations all results are sufficiently general to accommodate the use of a transactions costs adjusted hedging volatility and an asset rate of return that differs from the risk free rate of return

risky debt investment incentives and reputation in a sequential equilibrium the agency relationship of corporate insiders and bondholders is modeled as a dynamic game with asymmetric information the incentive effect of risky debt on the investment policy of a levered firm is studied in this context in a sequential equilibrium of the model a concept of reputation arises endogenously resulting in a partial resolution of the classic agency problem of underinvestment the incentive of the firm to underinvest is curtailed by anticipation of favorable rating of its bonds by the market this anticipated pricing of debt is consistent with rational expectations pricing by a competitive bond market and is realized in equilibrium some empirical implications of the model for bond rating debt covenants and bond price response to investment announcements are explored

improved estimates and forecasts of error correction models in economics abstract this paper is concerned with improved estimation and better forecasting of major economic activity within the context of error correction ec models as pioneered by sargan in 1964 and extended by numerous economists over the past three decades a new and general econometric methodology with superior average mean squared errors mse for ec models is introduced and for illustration applied to the estimation and forecasting of private consumption and demand for money in australia for the period 1960 1992 the improvement in terms of historical and ex post forecasting mse of our new methodology over the conventional statistical approaches currently in use for ec models is found to be up to 15 43

optimal multiperiod contracts and the gain from enduring relationships under private information informational asymmetries can play a key role in explaining the existence and nature of multiperiod contracts in an illustrative risk sharing model even relatively short two period contracts can be mutually beneficial if there is private information though one period contracts suffice otherwise further contracts which are pareto optimal relative to the environment and the information structure are defined and partially characterized an example illustrates how otherwise inefficient intertemporal tie ins can be used optimally to mitigate incentive problems the obvious borrowing lending schemes are not private information pareto optimal in these period by period actions are not sufficiently constrained discounting affects the form of the optimal contract but none of these qualitative conclusions

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

a theory of wage dynamics a dynamic equilibrium model of long term implicit labour contracts under incomplete but symmetric information is developed workers are assumed to be risk averse and of unknown ability or productivity risk neutral firms learn as do workers about each worker s productivity by observing the worker s output over time it is shown that equilibrium contracts provide for wages which never decline with age and increase only when the worker s market value increases above his current wage in addition to characterizing the equilibrium wage contract we also derive some of its implications for the behaviour of aggregate wages across various groups of workers these implications explain some findings in the recent empirical literature on ageearnings profiles in particular our model can explain why earnings may be positively related to experience even after controlling for productivity as some empirical studies have indicated

bogus joint liability groups in microfinance abstract in a random sample of clients of cfpam the largest microlender in china 73 of all joint liability groups practice lei da hu that is one person uses all group members loans in a single project we call such borrower groups bogus groups the lei da hu practice violates a key premise of group lending that each borrower must use their loan in a separate project what we call standard group we extend the theory of group lending by analyzing the endogenous formation and coexistence of standard and bogus groups and characterize the efficient lending terms the chosen group form depends on the borrower productivities and probability of success bogus groups are formed by heterogeneous borrowers when the gains from larger expected output exceed the foregone default risk diversification accounting for bogus groups in their lending strategy can help mfis raise productive efficiency and borrower welfare

the measurement of option mispricing abstract different studies have examined the ability of the black scholes option pricing model to estimate accurately market prices of publicly traded options and reached conflicting results this study examines commonly used ex ante measures of option mispricing finds that they can produce differing conclusions about option prices and develops an alternative measure for gauging option mispricing empirical analysis of returns to options selected using the various mispricing measures indicates that this new measure is more likely to detect mispricing and identify options that yield excess returns before commissions

two period financial contracts with private information and costly state verification townsend 1982 and others have argued that in a multiperiod context linked contracts may be pareto efficient relative to the private information environment the similarities with the supergame literature are well documented townsend 1982 p 1169 remarks the key idea of supergames is that future payoffs to the decision maker are tied to present actions of the decision maker in this context by linking contracts together an informed agent may be induced to report more honestly than in a singleperiod agreement in other words honesty may become the best policy in recent work allen 1985 and fudenberg et al 1990 show that in a private information environment with no precommitment the gains to long term contracting income smoothing in models such as townsend 1982 are in fact due to restrictions on borrowing and saving in particular if the entrepreneur can access capital markets freely and on the same terms as the bank then long term contracts will be no better than a sequence of short term contracts in the repeated model the role of tie ins then reflects little more than the fact that opportunities depend upon wealth as in the full information decentralized solution in this paper the entrepreneur only cares about his final payoff so that we do not establish a role for long term contracts as a means of smoothing income instead as suggested by hart and holmstrom 1986 we argue that long term contracts derive from an inability to costlessly verify contingencies in particular if output realizations of projects are not costlessly verifiable a long term contract may then be used to induce truthful revelations that cannot be supported by a sequence of short term contracts this leads to a saving of verification costs over allocations achieved with unlinked contracts this argument contributes to understanding why firms with known future prospects do not finance projects separately but instead enter into long term relationships with banks we examine a two period version of the borrower lender problem of gale and hellwig 1985 and townsend 1979 in this

the role of group size in group lending abstract this paper explores group size in joint liability lending primarily in the adverse selection framework with local borrower information a single standardized contract that imposes full joint liability subject to a limited liability cap is optimal further if gross returns to borrowing are moderately high this contract results in perfectly efficient lending if groups are large enough however raising group size accomplishes nothing if there is no local borrower information these results show that more is required for efficient lending than full within group insurance and highlight a complementarity between group size and social capital very similar results are shown in two different settings ex ante and ex post moral hazard though the type of social capital that complements group size varies across the settings taking a step toward modeling drawbacks of larger groups it is shown that if information deteriorates sufficiently with group size an intermediate group size does better than either extreme simulations suggest that most of the efficiency gains from larger groups are realized in group sizes below ten and that outreach and efficiency can increase dramatically when a moderate group size threshold is crossed

the dynamics of incentive contracts the paper studies a simple two period principal agent model in which the principal updates the incentive scheme after observing the agent s first period performance the agent has superior information about his ability the principal offers a first period incentive scheme and observes some measure of the agent s first period performance cost or profit which depends on the agent s ability and unobservable first period effort the relationship is entirely run by short term contracts in the second period the principal updates the incentive scheme and the agent is free to accept the new incentive scheme or to quit the strategies are required to be perfect and updating of the principal s beliefs about the agent s ability follows bayes rule the central theme of the paper is that the ratchet effect leads to much pooling in the first period first for any first period incentive scheme there exists no separating equilibrium second when the uncertainty about the agent s ability is small the optimal scheme must involve a large amount of pooling the paper also gives necessary and sufficient conditions for the existence of partition equilibria and looks at the effect of cost uncertainty

observing unobservables identifying information asymmetries with a consumer credit field experiment information asymmetries are important in theory but difficult to identify in practice we estimate the presence and importance of hidden information and hidden action problems in a consumer credit market using a new field experiment methodology we randomized 58 000 direct mail offers to former clients of a major south african lender along three dimensions i an initial offer interest rate featured on a direct mail solicitation ii a contract interest rate that was revealed only after a borrower agreed to the initial offer rate and ii a dynamic repayment incentive that was also a surprise and extended preferential pricing on future loans to borrowers who remained in good standing these three randomizations combined with complete knowledge of the lender s information set permit identification of specific types of private information problems our setup distinguishes hidden information effects from selection on the offer rate via unobservable risk and anticipated effort from hidden action effects via moral hazard in effort induced by actual contract terms we find strong evidence of moral hazard and weaker evidence of hidden information problems a rough estimate suggests that perhaps 13 to 21 of default is due to moral hazard asymmetric information thus may help explain the prevalence of credit constraints even in a market that specializes in financing high risk borrowers

group lending with sequential financing contingent renewal and social capital this paper focuses on the dynamic aspects of group lending in particular sequential financing and contingent renewal we examine the efficacy of these two schemes in harnessing social capital we find that for the appropriate parameter configurations there is homogenous group formation so that the lender can ascertain the identity of a group without lending to all its members thus screening out bad borrowers partially moreover under certain parameter configurations negative assortative matching occurs as a robust phenomenon

understanding index option returns this paper studies the returns from investing in index options previous research documents significant average option returns large capm alphas and high sharpe ratios and concludes that put options are mispriced we propose an alternative approach to evaluate the significance of option returns and obtain different conclusions instead of using these statistical metrics we compare historical option returns to those generated by commonly used option pricing models we find that the most puzzling finding in the existing literature the large returns to writing out of themoney puts is not even inconsistent with the black scholes model moreover simple stochastic volatility models with no risk premia generate put returns across all strikes that are not inconsistent with the observed data at the money straddle returns are more challenging to understand and we find that these returns are not inconsistent with explanations such as jump risk premia peso problems and estimation risk

an all encompassing consumption function the australian case abstract the paper reports some empirical findings of the davidson hendry srba and yeo 1978 consumption function fitted to australian quarterly data for the period 1969 3 to 1982 2 the evidence rejects in terms of the maximum likelihood ratio test the unitary differencing and price homogeneity restrictions and supports a simple dynamic forecasting model with unconstrained parameters

credit layering in informal financial markets abstract informal lenders with access to markets or capital often find it attractive to delegate loan provision to downstream lenders who have an information or enforcement advantage in dealing with particular borrowers in this paper we examine the conditions under which such an arrangement is preferred by two informal lenders a landlord and a merchant who compete in loan provision to tenant farmers differentiated by wealth we show that credit layering is preferred only when tenants are sufficiently poor in this case the trader lends to tenant farmers via a contract with their landlord otherwise only the trader lends as a consequence a pattern of borrowing emerges in which relatively wealthy tenants borrow from merchants while poor tenants borrow mainly from their landlords interlinkage between land and credit thus arises only for a subset of tenants and purely as a consequence of credit layering this pattern is shown to be supported empirically

joint liability lending and the peer selection effect we show that the joint liability lending contracts derived in ghatak 2000 violate an ex post incentive compatibility constraint which says that the amount of joint liability cannot exceed the amount of individual liability we derive and characterise optimal separating joint liability contracts incorporating this constraint

peer monitoring and credit markets a major problem for institutional lenders is ensuring that borrowers exercise prudence in the use of the funds so that the likelihood of repayment is enhanced one partial solution is peer monitoring having neighbors who are in a good position to monitor the borrower be required to pay a penalty if the borrower goes bankrupt peer monitoring is largely responsible for the successful financial performance of the grameen bank of bangladesh and of similar group lending programs elsewhere but peer monitoring has a cost it transfers risk from the bank which is in a better position to bear risk to the cosigner in a simple model of peer monitoring in a competitive credit market this article demonstrates that the transfer of risk leads to an improvement in borrowers welfare

dynamic microlending under adverse selection can it rival group lending we derive an optimal lending contract in a two period adverse selection model with limited commitment on the borrower side the contract involves penalty interest rates after default and favorable rates after success under some conditions it also charges first time borrowers higher rates than repeat borrowers as in relationship lending because the lender is constrained to keep borrowing attractive while using revealed information to price for risk we compare the efficiency of a group lending contract of the kind popularized by the microcredit movement to the dynamic individual contract both types of contracts reveal the same information but the contracts face different constraints on using the information to improve risk pricing as a result either type of contract can lead to greater efficiency depending on specifics of the environment opening the possibility that dynamic lending has played a role comparable to that of group lending in the success of microcredit we also characterize the optimal dynamic group contract when both lending techniques are feasible and find that it combines both approaches but with varying emphases a recurrent theme is that in more marginal environments dynamic lending performs relatively better than and is prioritized over group lending we also discuss a number of extensions including spatially and serially correlated risk and the effect of competition

an analysis of the risk in discretely rebalanced option hedges and delta based techniques the stochastic properties of discretely rebalanced option hedges have been studied extensively beginning with black and scholes 1973 in each analysis hedges were delta neutral after rebalancing we argue that the distributional properties of discretely rebalanced hedges are such that delta based hedging is not the variance minimizing strategy this paper obtains analytical expressions for the variance minimizing option hedge ratios we also evaluate the hedge variance to assess the magnitude of the variance reduction over delta based hedges for representative parameter values we show that systematic departures from delta based hedges can yield significant reductions in hedge variance even for one day rebalancing intervals

group lending under asymmetric information abstract this paper examines joint liability loan contracts as part of a screening mechanism adopted by lenders using group lending schemes a model and one period game are introduced in order to analyze the type of optimal loan contracts that emerge when lenders have less information than borrowers it is shown that under imperfect information lenders may be able to utilize joint liability contracts as a means of screening agent types by inducing endogenous group formation and self selection among the borrowers

competing lending platforms endogenous reputation and fragility in microcredit markets this paper shows that market fragility and mass default can arise in microcredit markets as a result of the strategic interaction between a microlender using a reputation based mechanism and a traditional lender using physical collateral in our model borrowers solve a dynamic programming problem which induces an endogenous equilibrium distribution of reputational capital because the quality of each lender s pool of borrowers is affected by both lenders interest rates lender reaction curves are non monotonic and discontinuous this can result in knife edge equilibria and mass default on the microlender precipitated by minor parametric perturbations fragility is exacerbated by borrower screening and sovereign risk but ameliorated when microlenders have social welfare goals our results highlight the importance of studying the entire credit market rather than microfinance in isolation

repeated moral hazard and one sided commitment abstract this paper considers a repeated unobserved endowment economy with a restriction that agents can walk away from insurance contracts at the beginning of any period and contract with another insurer one sided commitment an equilibrium is derived characterized by a unique market determined insurance contract with the property that agents never want to walk away from it the paper shows that trade or insurance still occurs and that a non degenerate long run distribution of consumption exists a numerical example shows that this distribution is nearly log normal journal of economic literature classification numbers d30 d31 d80 d82

returns of claims on the upside and the viability of u shaped pricing kernels abstract when the pricing kernel is u shaped then expected returns of claims with payout on the upside are negative for strikes beyond a threshold determined by the slope of the u shaped kernel in its increasing region and have negative partial derivative with respect to strike in the increasing region of the kernel using returns of i s p 500 index calls ii calls on major international equity indexes iii digital calls iv upside variance contracts and v a theoretical construct that we denote as kernel call we find broad support for the implications of u shaped pricing kernels a possible theoretical reconciliation of our empirical findings is explored through a model that accommodates heterogeneity in beliefs about return outcomes and short selling

long term financial contracts can mitigate the adverse selection problem in project financing this paper shows that long term contracts can be used in competitive financial markets to separate entrepreneurs of different abilities in equilibrium poor entrepreneurs are financed with a sequence of standard debt contracts good entrepreneurs are financed with a modified contract in which the terms of the second part of the contract are contingent upon whether default is observed at the first date sorting is achieved through the contingent term in the contract in equilibrium good entrepreneurs will typically pay high interest rates to start with followed by relatively lower rates later if they are successful the solution in the paper is contrasted with the use of collateral incomplete information plays an important role in explaining the existence and form of enduring relationships when agents have private information and cannot precommit to future actions and announcements there may be a role for multiperiod contracts see townsend 1982 and hart and holmstrom 1986 such contracts tie future contractual terms to current behaviour moreover these contracts can be self enforcing simply relying upon the self interest of agents to see them through this paper shows that long term relationships may help overcome adverse selection problems the basic idea is very simple entrepreneurs have different probabilities of completing successive projects successfully observation of the returns cannot reveal the type of project however repeated observation of returns does give information about the type of project by the law of large numbers even if there are only two observations at successive dates it may be possible to separate types by making the terms of the contract at the second date conditional upon whether default is observed at the first we consider an entrepreneur who is risk neutral and who has a project at each of two successive dates the projects may require outside finance from banks risk neutral banks offer two period credit contracts to the entrepreneur we assume that there are two types of entrepreneur one with a high probability of completing projects successfully and a second with a low probability the probability of success is private information to the entrepreneur it is not known by the bank the problem of generalising the analysis to more entrepreneur types is discussed in the conclusion in section 2 of the paper it is shown that in this setting an adverse selection problem may arise we consider a sequence of standard debt contracts which specify a fixed payment at each date the important point to note here is that with

group lending local information and peer selection this paper analyzes how group lending programs use joint liability to utilize local information that borrowers have about each other s projects through self selection of group members in the group formation stage these schemes are shown to lead to positive assortative matching in group formation faced with the same contract this makes the effective cost of borrowing lower to safer borrowers because they have safer partners conditional on success their expected dues to the lender are lower than that of riskier borrowers the resulting improvement in the pool of borrowers is shown to increase repayment rates and welfare q 1999 elsevier science b v all rights reserved

the life cycle of a microfinance institution the irish loan funds abstract ireland s loan funds were a long lived self sustaining large scale microfinance organization that made millions of loans without collateral to the poor during the first 100 years of their life cycle a period of growth ending in the 1840s they adapted constantly and obtained improvements to their legal structure because they were complementary to the banking system and seen as effective in relieving poverty in their 2nd century they became ossified in part because of competition with commercial banks the loan funds provide an example of sustainable microfinance under harsh economic conditions and illustrate how organizations change incrementally and when successful alter their institutional framework

group versus individual liability short and long term evidence from philippine microcredit lending groups abstract group liability in microcredit purports to improve repayment rates through peer screening monitoring and enforcement however it may create excessive pressure and discourage reliable clients from borrowing two randomized trials tested the overall effect as well as specific mechanisms the first removed group liability from pre existing groups and the second randomly assigned villages to either group or individual liability loans in both groups still held weekly meetings we find no increase in short run or long run default and larger groups after three years in pre existing areas and no change in default but fewer groups created after two years in the expansion areas

income fluctuation and asymmetric information an example of a repeated principal agent problem we examine a simple repeated principal agent model with discounting there are a risk averse borrower with an unobservable random income and a risk neutral lender the efficient contract is characterized it tends to the first best constant consumption contract as the discount factor tends to one and the time horizon extends to infinity if the time horizon is infinite and the contract is legally enforceable the borrower s utility becomes arbitrarily negative with probability one if the borrower has constant absolute risk aversion consumption is transferred between any two states at a constant interest rate which is less than the rate of time preference

screening by the company you keep joint liability lending and the peer selection effect we look at an economic environment where borrowers have some information about the nature of each other s projects that lenders do not we show that joint liability lending contracts similar to those used by credit cooperatives and group lending schemes will induce endogenous peer selection in the formation of groups in a way that the instrument of joint liability can be used as a screening device to exploit this local information this can improve welfare and repayment rates if standard screening instruments such as collateral are unavailable

information and enforcement in informal credit markets we study loan enforcement in informal credit markets with multiple lenders but no sharing of credit histories and derive the dynamics of loan size and interest rates for relational lending in the presence of a sufficient fraction of natural defaulters the rest of the market can be incentivized against default by micro rationing sharper credit limits and possibly higher interest rates that serve as gateways into new borrowing relationships when there are too few natural defaulters in the market this can be supplemented by macro rationing random exclusion of some borrowers when information collection is endogenized multiple equilibria may arise

assortative matching adverse selection and group lending abstract this note reconsiders a theoretical result asserted to explain the success of group lending programs in ldcs it has been claimed that if groups are allowed to form themselves risky and safe borrowers will sort themselves into relatively homogenous groups this positive assortative matching can be exploited by lenders to solve an adverse selection problem that would otherwise undermine the effectiveness of such lending programs i show that the positive assortative matching result does not necessarily hold if earlier models are extended to incorporate dynamic incentives

repayment incentives and the distribution of gains from group lending group loans with joint liability are a distinguishing feature of many microfinance programs while such lending benefits millions of borrowers major lending institutions acknowledge its limited impact among the very poor and have shifted towards individual loans this paper attempts to explain this trend by exploring the relationship between borrower wealth and the benefits from group lending when access to credit is limited by strategic default in our model individuals of heterogeneous wealth face a given investment opportunity so poor investors demand larger loans we show that the largest loan offered as an individual contract cannot be supported as a group loan joint liability cannot therefore extend credit outreach in the absence of additional social sanctions within groups we also find that the benefits from group loans are increasing in borrower wealth and that optimal group size depends on project characteristics by allowing for multi person groups and wealth heterogeneity in the population the paper extends the standard framework to analyze joint liability and contributes to an understanding of the conditions under which microcredit can reduce poverty

a simple formula for the expected rate of return of an option over a finite holding period under conditions consistent with the black scholes formula a simple formula is developed for the expected rate of return of an option over a finite holding period possibly less than the time to expiration of the option under these conditions surprisingly the expected future value of a european option even prior to expiration is shown equal to the current black scholes value of the option except that the expected future value of the stock at the end of the holding period replaces the current stock price in the black scholes formula and the future value of a riskless invesment of the striking price replaces the striking price an extension of this result is used to approximate moments of the distribution of returns from an option portfolio