bounded price variation and rational expectations in endogenous switching model of the u s corn market a model that includes bounded price variation and rational expectations by producers is estimated for the u s corn market the resulting model specification is highly nonlinear though since the probability of market equilibrium must be determined endogenously unlike previous research the cross equation restrictions implied by the rational expectations hypothesis are incorporated in the bounded prices model by using fair and taylor s 1983 procedure for obtaining maximum likelihood estimates of nonlinear rational expectations models the resulting model is compared against a standard equilibrium model with naive expectations the results show the bounded prices model is a superior specification copyright 1989 by mit press

the distributional implications of asymmetric income dynamics abstract income dynamics differ between groups of households defined by whether the head has university education or not and have changed asymmetrically in great britain since 2008 using a heterogeneous agent incomplete markets model we examine the quantitative implications of these differences for wealth inequality and for the distribution of conditional welfare losses within group wealth inequality is higher for the non university group and has increased since 2008 for both groups while between group inequality has also increased welfare losses are significantly higher for the non university educated since 2008 and are driven by both a greater fall in mean income and a larger rise in income risk non university educated households which had initial wealth below the median and net labour income in the lower quintiles suffered bigger losses social insurance policies beyond those currently in place can mitigate such welfare losses via tax and benefit redistributive mechanisms for the broad majority of households social insurance is valued more when it insures against the big adverse income shocks

an impossibility theorem for wealth in heterogeneous agent models with limited heterogeneity abstract it has been conjectured that canonical bewley huggett aiyagari heterogeneous agent models cannot explain the joint distribution of income and wealth the results stated below verify this conjecture and clarify its implications under very general conditions we show in particular that if i agents are infinitely lived ii saving is risk free and iii agents have constant discount factors then the wealth distribution inherits the tail behavior of income shocks e g light tailedness or the pareto exponent our restrictions on utility require only that relative risk aversion is bounded and a large variety of income processes are admitted our results show conclusively that it is necessary to go beyond standard models to explain the empirical fact that wealth is heavier tailed than income we demonstrate through examples that relaxing any of the above three conditions can generate pareto tails

target zones and exchange rate dynamics this paper develops a simple model of exchange rate behavior under a target zone regime it shows that the expectation that monetary policy will be adjusted to limit exchange rate variation affects exchange rate behavior even when the exchange rate lies inside the zone and is thus not being defended actively somewhat surprisingly the analysis of target zones turns out to have a strong formal similarity to problems in option pricing and investment under uncertainty

wealth distribution with random discount factors abstract to explain the pareto tail behavior empirically observed in wealth distributions the quantitative macro literature has occasionally assumed that agents have random discount factors this paper formally proves that the stationary wealth distribution in a simple huggett model with random discounting has power law tails and characterizes the pareto exponents analytically i find that in general there is no clear relationship between the return on wealth and inequality and that the pareto exponent is highly sensitive to the persistence of the discount factor process i also provide a practical guidance for how to characterize the pareto exponents in richer models

papers in experimental economics competitive market institutions double auctions vs sealed bid offer auctions consider a market with the following characteristics 1 privacy that is each agent knows only his own valuation or cost conditions 2 exchange follows the rules of the oral double auction that is buyers freely announce bids or accept offers and sellers freely announce offers or accept bids 3 aggregate market supply and demand per trading period is stationary for at least two to three periods and 4 there are at least four buyers and as many sellers the literature reporting the results of a large number of experimental markets with these characteristics documents what appears to be a remarkably rapid convergence to a competitive equilibrium ce however any claim of double auction da convergence to the ce can only have meaning in one of three senses i the ce is attained immediately ii after t periods of trading some measure of the market s state such as mean price is nearer relative to experimental sampling variability to a ce than to some distinct alternative equilibrium such as a monopoly or nash equilibrium iii after t periods of trading this measure is nearer to a ce in da experimental markets than in markets organized under a different institution of contract for example a sealed bid auction since everything from electrons and the stars to rats and people yield state measures subject to error or random variation the deterministic criterion i can have no serious scientific standing by such criteria any hypothesis can be rejected and there could be no science of physics biology or economics 2 with the exception of certain very simple markets such as single object auctions or certain idealized markets such as the cournot quantity adjuster model economics has only two concepts of equilibrium monopoly and competitive the only formal model of da trading that has been proposed see david easley and john ledyard p 6 predicts stochastic convergence in finite time with probability one to a ce hence the only test alternative to the ce research hypothesis in da markets is a monopoly or monopsony equilibrium experimentalists have not reported statistical tests of the ce professor department of economics university of arizona assistant professor department of economics indiana university instructor department of economics university of arizona and sandia national laboratories albuquerque nm respectively we are indebted to the national science foundation for research support and to art denzau and mort kamien for helpful comments there is an early and recently growing body of experimental evidence for convergence to a competitive equilibrium under double auction rules the earliest evidence contained in experiments initiated in january 1956 is reported in smith 1962 1964 1965 1976 however these early experiments used between twenty and fifty or so participant buyers and sellers because in keeping with prevailing professional beliefs it was thought that a ce was unlikely to be approached unless numbers were quite large using large numbers was not unreasonable since it is a good beginning procedure to give a theory whatever is believed to be its best shot more recent evidence using six buyers six sellers and two traders in speculative da markets with cyclical demand is reported by r m miller charles plott and smith and williams 1979 for evidence from a comparison of oral and computerized da experiments with four buyers and four sellers see williams 1980 for further evidence in the context of the study of price controls see m isaac and plott 1981b and smith and williams 1981b in the context of a conspiracy study see isaac and plott 1981a in the context of comparisons between da and posted offer pricing see jon ketcham smith and williams in the context of a study of four variations on da rules see smith and williams 1980 all of these more recent papers report double auction experiments using no more than four buyers and four sellers 2as frederick mosteller once noted if you wanted to reject the inverse square law of attraction try tossing a sheet of paper out the window

existence of stationary equilibrium in an incomplete market model with endogenous labor supply in this article i first study an income fluctuation problem with endogenous labor supply let be the agent s time discount factor and r 0 be the constant gross rate of return on assets for r 1 i show that the agent s wealth either approaches infinity almost surely or converges to a finite level almost surely for r

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

random earnings differences lifetime liquidity constraints and altruistic intergenerational transfers abstract this paper develops a model of private savings behavior in which households care about their descendants cannot have negative net worth and have lifetime earnings depending on random draws from an exogenous distribution of abilities the elements interact very lucky parents are likely to leave large estates constrained children are unusually likely to receive intergenerational transfers the paper proves the existence of a stationary cross sectional distribution of wealth endogenously determines where liquidity constraints will bind and shows that the long term interest rate must be such that ricardian neutrality fails its last section generates several illustrative numerical simulations

saving and liquidity constraints this paper is concerned with the theory of saving when consumers are not permitted to borrow and with the ability of such a theory to account for some of the stylized facts of saving behavior the models presented in the paper seem to account for important aspects of reality that are not explained by traditional life cycle models copyright 1991 by the econometric society

auction design for composite goods the natural gas industry abstract experiments examine the price and efficiency performance of a simple production parallel transmission and wholesale consumption model of a natural gas pipeline system a center determines prices and allocations to buyers producers and transporters to maximize surplus based on the location specific bids of buyers producers and transporters efficiency tends to grow asymptotically to 100 in stationary environments prices stabilize quickly in the neighborhood of predicted competitive equilibrium levels over time agents settle into an equilibrium with elastic bid schedules and numerous tied bids and offers these strategies allow each agent class to protect itself from manipulation by the other classes

modeling expectations of bounded prices an application to the market for corn the presence of farm programs should directly affect the expectations of producers this paper analyzes the formation of price expectations when price supports constitute an effective lower bound on the distribution of the expectations we first investigate what the expected price would be if the usual rational expectations formula is used this leads to a relationship that is not estimable we suggest two alternatives one based on a tobit approximation and the other based on a perfect prediction of when the support is going to be effective using a simplified model of the u s corn market the methodology is demonstrated and compared to an alternative method of using futures prices as the expectation of harvest price the analysis of supply response for the major u s field crops is made difficult due to government intervention in these markets this intervention has been characterized by the use of price supports acreage diversion storage incentives etc during the last thirty years many studies have analyzed producer behavior in the presence of governmental involvement such studies have typically been concerned with modeling the effect of supports and diversions in an ex post sense rather than with how producers used the knowledge of farm programs to form their expectations if producers are rational economic agents their expectations of harvest prices should be conditioned both by free market forces and the type and degree of governmental intervention in the market of course farm programs have varied in nature and extent during the past thirty years and it is doubtful that any structural model could capture their complexities in this paper we attempt to introduce rational expectations in a simplified model of the u s corn market in essence we focus on the formation of price expectations when price supports constitute an effective lower bound on the distribution of the expectations we proceed by developing a theoretical model that connects the rational expectations model with a model of bounded price variation it is shown that one representation that may characterize the corn market is a triangular structural system with endogenous switching a full information maximum likelihood estimator is proposed for the system next an empirical model is specified and estimated the model is evaluated in comparison to an augmented model that contains a futures price so that some inferences may be made concerning the rational expectations model s success in summarizing relevant market information expectations under bounded prices consider a market that may be represented by a simple supply and demand system q a pt a2w el supply function pt b qt b2xt e2t demand function 1 where p and q represent market price and quantity w and x represent supply and demand shifters and p represents the rational expectation of product price at the time production decisions are made note that this system has a familiar recursive structure when the expected price variable is specified in terms of one or more lagged prices when the restricted reduced form of the structural system is solved for in terms of the expected price and this expression is used to replace pj wallis 1980 then models similar to those of goodwin and sheifrin 1982 and shonkwiler and emerson 1982

on the existence and uniqueness of stationary equilibrium in bewley economies with production abstract i prove existence of stationary recursive competitive equilibrium in bewley economies with production under specifications in which i the utility function is allowed to be unbounded and ii the underlying discrete idiosyncratic productivity process can take any form aside from mild restrictions some of the intermediate results provide theoretical basis for assumptions often made in the quantitative macroeconomics literature by providing an example i illustrate that the equilibrium is not necessarily unique even under typical specifications of the model and discuss the underlying reasons for multiplicity

non existence of recursive equilibria on compact state spaces when markets are incomplete abstract this paper analyzes one good exchange economies with two infinitely lived agents and incomplete markets it is shown that there are no recursive markov equilibria for which borrowing debt constraints never bind if the state space of exogenous and endogenous variables is a compact subset of r n moreover for large enough but finite borrowing limits no recursive equilibrium with compact state space exists these non existence results hold for any economy satisfying the following standard assumptions preferences are additively separable across time and states the one period utility function is time and state independent and unbounded from below endowments are bounded and follow a markov chain with stationary transition matrix there is some idiosyncratic risk and no aggregate risk

the expectations hypothesis of the term structure when interest rates are close to zero abstract in an economy where cash can be stored costlessly in nominal terms the nominal interest rate is bounded below by zero this paper derives the implications of this non negativity constraint for the term structure and shows that it induces a nonlinear and convex relation between short and long term interest rates the long term rate responds asymmetrically to changes in the short term rate and by less than that is predicted by the benchmark linear model in particular a decrease in the short term rate produces a smaller response in the long term rate than an increase of the same magnitude the empirical predictions of the model are examined using data from japan

incomplete markets labor supply and capital accumulation we explore the accumulation of capital in the presence of limited insurance against idiosyncratic shocks borrowing constraints and endogenous labor supply in the exogenous labor supply case e g aiyagari 1994 huggett 1997 the presence of limited insurance increases the demand for savings for precautionary reasons as a consequence capital and output are higher under incomplete markets we show that if labor hours are endogenous labor supply is likely to be lower under incomplete markets because those agents who experience a high shock to productivity are ex post richer and they work fewer hours in some cases this wealth effect can overcome the aggregate precautionary savings and give rise to lower savings and output under incomplete

allocating uncertain and unresponsive resources an experimental approach we identify an important class of economic problems that arise naturally in several applications the allocation of multiple resources when there are uncertainties in demand or supply unresponsive supplies no inventories and fixed capacities and significant demand indivisibilities rigidities examples of such problems include scheduling job shops airports or supercomputers zero inventory planning and the allocation and pricing of nasa s planned space station using experimental methods we show that the two most common organizations used to deal with this problem markets and administrative procedures can perform at very low efficiencies 60 65 efficiency in a seemingly robust example thus there is a need to design new mechanisms that more efficiently allocate resources in these environments we develop and analyze two mechanisms that arise naturally from auctions used to allocate single dimensional goods these new mechanisms involve computer assisted coordination made possible by the existence of networked computers both mechanisms significantly improve on the performance of administrative and market procedures

huggett economies with multiple stationary equilibria abstract i obtain a closed form solution to a huggett economy with constant absolute risk aversion cara utility when the vector of individual state variables follows a var 1 process with an arbitrary shock distribution the stationary equilibrium is unique if the income process is ar 1 but not necessarily so otherwise with gaussian shocks i provide general sufficient conditions for the existence of at least three equilibria when the income process is either arma 1 1 ar 2 or has a persistent transitory pt representation with negatively correlated shocks the possibility of multiple equilibria calls for caution in comparative statics exercises and policy analyses using heterogeneous agent models as an illustration i provide an example in which the welfare implication of changing the income risk goes in opposite directions depending on the choice of equilibrium

income and wealth heterogeneity in the macroeconomy how do movements in the distribution of income and wealth affect the macroeconomy we analyze this question using a calibrated version of the stochastic growth model with partially uninsurable idiosyncratic risk and movements in aggregate productivity our main finding is that in the stationary stochastic equilibrium the behavior of the macroeconomic aggregates can be almost perfectly described using only the mean of the wealth distribution this result is robust to substantial changes in both parameter values and model specification our benchmark model whose only difference from the representative agent framework is the existence of uninsurable idiosyncratic risk displays far less cross sectional dispersion and skewness in wealth than u s data however an extension that relies on a small amount of heterogeneity in thrift does succeed in replicating the key features of the wealth data furthermore this extension features aggregate time series that depart significantly from permanent income behavior

the effect of interest rates on consumption in an income fluctuation problem abstract we examine the effect of a change in interest rates on an agent s consumption and savings decisions when her income is fluctuating in each period a long lived agent decides how much to save i e invest in a risky bond and how much to consume while her income and the rate of return on her savings are uncertain and depend on the state of the economy we show that under the concavity of the consumption function a condition that ensures that the substitution effect dominates the income effect lower interest rates encourage the agent s consumption across all states

on income fluctuations and capital gains abstract we consider the infinite time horizon problem of asymptotically maximizing the expected accumulated discounted utility in a one good production economy the available capital in a given period is given by the production of the previous period plus a random variable the product of the discount and interest factors is either 1 greater than or 2 equal to one under 1 the optimal policy exists under certain conditions and always under 2 the optimal capital sequence almost surely goes to infinity under 1 with conditions on the utility one almost surely reaches a capital level above which the sequence is increasing

consumption liquidity constraints and asset accumulation in the presence of random income fluctuations recent empirical research flavin 1981 hagashi 1982 has rejected the certainty equivalent formulation of permanent income hypothesis hall 1978 these findings are often attributed to households inability to borrow completely against expected future labor income this paper is a theoretical investigation of optimal consumption behavior under risk aversion random income fluctuations and borrowing restrictions our principle objective is to establish the existence and to investigate the properties of the stationary probability distribution which characterizes the asymptotic behavior of consumption under these conditions this abstract was borrowed from another version of this item

the wealth distribution in bewley economies with capital income risk abstract we study the wealth distribution in bewley economies with idiosyncratic capital income risk we show analytically that under rather general conditions on the stochastic structure of the economy a unique ergodic distribution of wealth displays a fat tail

testing the expectations hypothesis when interest rates are near integrated nominal interest rates are unlikely to be generated by unit root processes using data on short and long interest rates from eight developed and six emerging economies we test the expectations hypothesis using cointegration methods under the assumption that interest rates are near integrated if the null hypothesis of no cointegration is rejected we then test whether the estimated cointegrating vector is consistent with that suggested by the expectations hypothesis the results show support for cointegration in 10 of the 14 countries we consider and the cointegrating vector is similar across countries however the parameters differ from those suggested by theory we relate our findings to existing literature on the failure of the expectations hypothesis and to the role of term premia

endogenous partial insurance and inequality in this paper we propose a model of endogenous partial insurance and we investigate its implications for macroeconomic outcomes such as wealth inequality asset accumulation interest rate and consumption smoothing to this end we include participation costs to state contingent asset markets into an otherwise standard aiyagari 1994 model we highlight the resulting nonmonotonic relationship between wealth and insurance market participation when insurance is costly poor households remain uninsured middle class households participate in the insurance market whereas rich households decide to self insure by only purchasing risk free assets after theoretically characterizing the endogenous partial insurance equilibrium we quantify its effect emphasizing the roles of a participation channel and an interest rate channel

subprime mortgage default abstract this paper constructs a reduced form credit risk model of mortgage default the data used is of privately securitized subprime arms adjustable rate mortgages originated between 1997 and 2008 and observed between 2000 and 2009 the period studied thus encompasses the beginning of the subprime crisis given the estimated model contractual properties of the loans are then used to infer the market price of default risk for the various quarters of origination it is empirically determined that a change in the inherent nature of borrowers led to a deterioration in their default performance a change which can be first detected in late 2004 on the other hand the evidence also indicates that the secondary mortgage market became aware of this change at about this same time the large rise in defaults in 2007 cannot therefore be attributed to any surprise other than the unexpectedly large fall in housing prices

aggregate precautionary savings when is the third derivative irrelevant abstract when are aggregate precautionary savings positive we address this question in the context of a general equilibrium model where infinitely lived agents receive idiosyncratic labor endowment shocks hold a risk free asset to smooth consumption and face a liquidity constraint we prove that 1 the steady state capital stock is always larger in any equilibrium with idiosyncratic shocks and a liquidity constraint than without idiosyncratic shocks i e aggregate precautionary savings are positive as long as consumers are risk averse and 2 aggregate precautionary savings occurs if and only if the liquidity constraint binds for some agents

the risk free rate in heterogeneous agent incomplete insurance economies abstract why has the average real risk free interest rate been less than one percent the question is motivated by the failure of a class of calibrated representative agent economies to explain the average return to equity and risk free debt i construct an economy where agents experience uninsurable idiosyncratic endowment shocks and smooth consumption by holding a risk free asset i calibrate the economy and characterize equilibria computationally with a borrowing constraint of one year s income the resulting risk free rate is more than one percent below the rate in the comparable representative agent economy

a realistic model for official interest rate movements and their consequences this article extends the vector autoregression var methodology to examine the consequences of monetary policy decisions by considering two types of nonlinearities in the determination of official interest rates 1 the asymmetry related to the different nature of the discrete and infrequent positive and negative interest rate movements determined by central bankers and 2 the convexity in the transmission of policy shocks induced by the nonnegativity constraint in interest rates for the uk we find some evidence of both types of asymmetries in the us responses to unexpected interest rate shocks are far more symmetric results highlight the importance of considering all types of asymmetries when studying monetary transmission

analysis of exchange rate target zones using a limited dependent rational expectations model with jumps this article examines the exchange rate determination in a target zone regime when the bounds can be fixed for an extended period but are subject to occasional jumps in this case the behavior of the endogenous variable is affected by the agents expectations about both the occurrence and the size of the jump empirical results using data for the franc mark exchange rate provide support for the nonlinear model with time varying realignment probability and indicate that the agents correctly anticipated most of the observed changes in the central parity

when do borrowing constraints bind some new results on the income fluctuation problem abstract the empirical failure of the permanent income hypothesis has prompted researchers to investigate models in which consumers are liquidity constrained as shown in deaton econometrica 59 5 1991 1221 liquidity constrained consumers might choose to exhaust their borrowing capacity from time to time yet due to technical limitations the conditions under which this behavior arises have not been investigated the present paper extends the class of solvable models in a way that allows this issue to be dealt with it turns out that under the loosest sustainable borrowing constraint the agent might systematically avoid exhausting his borrowing capacity

international lending and borrowing in a stochastic stationary equilibrium this paper develops a simple general equilibrium model of international borrowing and lending in which national products are subject to random fluctuations international capital flows arise from the efforts of risk averse households in different countries to self insure against random income fluctuations by accumulating foreign claims that can be used to finance a less variable profile of consumption relative to national income in the absence of aggregate uncertainty a stationary rational expectations equilibrium is shown to exist despite the fact that rates of time preference differ among countries a number of results many of which enrich those in the existing literature are obtained copyright 1990 by economics department of the university of pennsylvania and the osaka university institute of social and economic research association

precautionary saving in the small and in the large the theory of precautionary saving is shown to be isomorphic to the arrow pratt theory of risk aversion making possible the application of a large body of knowledge about risk aversion to precautionary saving and more generally to the theory of optimal choice under risk in particular a measure of the strength of the precautionary saving motive analogous to the arrow pratt measure of risk aversion is used to establish a number of new propositions about precautionary saving and to give a new interpretation of the dreze modigliani substitution effect copyright 1990 by the econometric society

recursive equilibria in an aiyagari style economy with permanent income shocks in this paper we prove the existence of a recursive competitive equilibrium rce for an aiyagari style economy with permanent income shocks and perpetual youth structure we show that there exist equilibria where borrowing constraints are never binding this allows us to establish a non trivial lower bound on the equilibrium interest rate to solve the individual s problem we present a new approach that uses lattices of consumption functions to deal with the non compact state space and the unbounded utility function the approach uses only the first order conditions of the problem euler equations the proof is constructive and it serves as a theoretical foundation for the convergence of a policy function iteration procedure