microstructure noise realized variance and optimal sampling a recent and extensive literature has pioneered the summing of squared observed intra daily returns realized variance to estimate the daily integrated variance of financial asset prices a traditional object of economic interest we show that in the presence of market microstructure noise realized variance does not identify the daily integrated variance of the frictionless equilibrium price however we demonstrate that the noise induced bias at very high sampling frequencies can be appropriately traded off with the variance reduction obtained by high frequency sampling and derive a mean squared error mse optimal sampling theory for the purpose of integrated variance estimation we show how our theory naturally leads to an identification procedure which allows us to recover the moments of the unobserved noise this procedure may be useful in other applications finally using the profits obtained by option traders on the basis of alternative variance forecasts as our economic metric we find that explicit optimization of realized variance s finite sample mse properties results in accurate forecasts and considerable economic gains copyright 2008 wiley blackwell

futures prices on yields forward prices and implied forward prices from term structure when futures contracts are settled with respect to underlying asset prices received theory suggests that the differences between futures prices and implied forward prices from the term structure are strictly due to marking to market ceteris paribus empirical evidence appears to indicate that such differences are small for contracts with short maturities what happens when the futures contract settles to yields implied by future prices of underlying assets the eurodollar futures contract which is the most actively traded futures contract in the united states settles to yield as opposed to prices this unique settlement feature is shown to imply that the implied forward prices from the libor term structure should differ from the futures prices even in the absence of marking to market differences due to marking to market effect are small they are shown to vary between 2 to 45 basis points less than one half percent of futures prices on the other hand differences between implied forward prices and futures prices are shown to be relatively large

option pricing when the variance changes randomly theory estimation and an application in this paper we examine the pricing of european call options on stocks that have vari ance rates that change randomly we study continuous time diffusion processes for the stock return and the standard deviation parameter and we find that one must use the stock and two options to form a riskless hedge the riskless hedge does not lead to a unique option pricing function because the random standard deviation is not a traded security one must appeal to an equilibrium asset pricing model to derive a unique option pricing function in general the option price depends on the risk premium associated with the random standard deviation we find that the problem can be simplified by assuming that volatility risk can be diversified away and that changes in volatility are uncorrelated with the stock return the resulting solution is an integral ofthe black scholes formula and the distribution function for the variance of the stock price we show that accurate option prices can be computed via monte carlo simulations and we apply the model to a set of actual prices

answering the skeptics yes standard volatility models do provide accurate forecasts a voluminous literature has emerged for modeling the temporal dependencies in financial market volatility using arch and stochastic volatility models while most of these studies have documented highly significant in sample parameter estimates and pronounced intertemporal volatility persistence traditional ex post forecast evaluation criteria suggest that the models provide seemingly poor volatility forecasts contrary to this contention we show that volatility models produce strikingly accurate interdaily forecasts for the latent volatility factor that would be of interest in most financial applications new methods for improved ex post interdaily volatility measurements based on high frequency intradaily data are also discussed

bargaining and the timing of investment the joint determination of the timing of investment and wage bargaining is modelled two cases are considered a there is an alternating offer bargaining game over binding wage contracts and production is possible only when agreement is reached b there are no binding contracts so revenue is divided in period by period bargaining post investment investment can occur earlier in case b than in case a and the equilibrium in case b can pareto dominate the equilibrium with binding contracts these conclusions depend on players discount factors

the pricing of options on assets with stochastic volatilities one option pricing problem that has hitherto been unsolved is the pricing of a european call on an asset that has a stochastic volatility this paper examines this problem the option price is determined in series form for the case in which the stochastic volatility is independent of the stock price numerical solutions are also produced for the case in which the volatility is correlated with the stock price it is found that the black scholes price frequently overprices options and that the degree of overpricing increases with the time to maturity one option pricing problem that has hitherto remained unsolved is the pricing of a european call on a stock that has a stochastic volatility from the work of merton 12 garman 6 and cox ingersoll and ross 3 the differential equation that the option must satisfy is known the solution of this differential equation is independent of risk preferences if a the volatility is a traded asset or b the volatility is uncorrelated with aggregate consumption if either of these conditions holds the risk neutral valuation arguments of cox and ross 4 can be used in a straightfoward way this paper produces a solution in series form for the situation in which the stock price is instantaneously uncorrelated with the volatility we do not assume that the volatility is a traded asset also a constant correlation between the instantaneous rate of change of the volatility and the rate of change of aggregate consumption can be accommodated the option price is lower than the blackscholes b s 1 price when the option is close to being at the money and higher when it is deep in or deep out of the money the exercise prices for which overpricing by b s takes place are within about ten percent of the security price this is the range of exercise prices over which most option trading takes place so we may in general expect the b s price to overprice options this effect is exaggerated as the time to maturity increases one of the most surprising implications of this is that if the b s equation is used to determine the implied volatility of a near the money option the longer the time to maturity the lower the implied volatility numerical solutions for the case in which the volatility is correlated with the stock price are also examined the stochastic volatility problem has been examined by merton 13 geske 7 johnson 10 johnson and shanno 11 eisenberg 5 wiggins 16 and

a joint framework for consistently pricing interest rates and interest rate derivatives dynamic term structure models explain the yield curve variation well but perform poorly in pricing and hedging interest rate options most existing option pricing practices take the yield curve as given thus having little to say about the fair valuation of the underlying interest rates this paper proposes an m n model structure that bridges the gap in the literature by successfully pricing both interest rates and interest rate options the first m factors capture the yield curve variation whereas the latter n factors capture the interest rate options movements that cannot be effectively identified from the yield curve we propose a sequential estimation procedure that identifies the m yield curve factors from the libor and swap rates in the first step and the n options factors from interest rate caps in the second step the three yield curve factors explain over 99 of the variation in the yield curve but account for less than 50 of the implied volatility variation for the caps incorporating three additional options factors improves the explained variation in implied volatilities to over 99

price discovery in the u s treasury market the impact of orderflow and liquidity on the yield curve we examine the role of price discovery in the u s treasury market through the empirical relationship between orderflow liquidity and the yield curve we find that orderflow imbalances excess buying or selling pressure can account for as much as 26 percent of the day to day variation in yields on days without major macroeconomic announcements the effect of orderflow on yields is permanent and strongest when liquidity is low all of the evidence points toward an important role of price discovery in understanding the behavior of the yield curve

a welfare analysis of employment contracts with and without asymmetric information this paper provides a complete characterization of the welfare economics of employment contracts when workers are immobile in the ex post period necessary and sufficient conditions for constrained pareto optimality are derived for economies with incomplete risk markets two consumption goods and random production technologies in which a workers can cannot observe realizations of their employers revenue function symmetric vs asymmetric information and in which b employment contracts allow preclude contingent wages and or employment levels flexible vs rigid contracts this taxonomic approach serves to identify the welfare implications of exogenous and endogenous contractual rigidities and to isolate a class of externalities that is unique to economies with asymmetric information the latter market failure is also present with indexed contracts when workers alone can observe realizations of their consumption goods prices another form of asymmetric information

getting implicit shadow prices right for the estimation of the malmquist index the case of agricultural total factor productivity in developing countries abstract the malmquist index has become extensively used in international comparisons of agricultural productivity since it does not require prices for its estimation which are normally not available however the dea approach used to estimate this index still uses implicit price information this entails potential problems because these methods are susceptible to the effect of data noise and shadow prices can prove to be inconsistent with prior knowledge on cost shares in this paper we analyze implicit input shadow shares used in the dea approach to estimate agricultural productivity using the malmquist index for 72 developing countries we then set bounds to the implicit input shares introducing information on their likely value and compare constrained and unconstrained input shares we conclude that the incidence of zero shadow prices justifies the introduction of constraints in the estimation of the malmquist index the paper also presents detailed results of tfp growth in developing countries using constrained shadow shares for their estimation we find that agricultural tfp has been growing steadily in the past 20 years even if countries like china brazil and india are not considered remarkably we find a clear improvement in the performance of sub saharan africa since the mid 1980s key words malmquist shadow prices total factor productivity jel codes d2

pricing european currency options a comparison of the modified black scholes model and a random variance model we use the modified black scholes model and a random variance option pricing model to study prices of european currency options traded in geneva the options which cannot be exercised early include calls and puts on the dollar swiss franc exchange rate in the empirical analysis we examine the model fit and the biases with respect to the strike price time to maturity and volatility there is some evidence of mispricing and there are small gains available by trading with the random variance model

simulating weights restrictions in data envelopment analysis by means of unobserved dmus data envelopment analysis dea is a method for assessing the comparative efficiencies of decision making units e g banks and schools by relating their output to their input levels restrictions are often imposed in these assessments to reflect prior judgments on the values of input and or output variables this paper introduces a new approach to capturing and using value judgments in dea based on unobserved decision making units in so doing it opens up a whole new approach for reflecting value judgments in dea assessments which can offer advantages in certain situations

unspanned stochastic volatility and fixed income derivatives pricing we propose a parsimonious unspanned stochastic volatility model of the term structure and study its implications for fixed income option prices the drift and quadratic variation of the short rate are affine in three state variables the short rate its long term mean and variance which follow a joint markov vector process yet bond prices are exponential affine functions of only two state variables independent of the current interest rate volatility level because this result holds for an arbitrary volatility process such a process can be calibrated to match fixed income derivative prices furthermore this model can be extended by relaxing the time homogeneity to fit any arbitrary term structure in its hjm form this model nests the analogous stochastic equity volatility model of heston 190 heston s l 1993 a closed form solution for options with stochastic volatility review of financial studies 6 327 343 in particular if the volatility process is specified to be affine closed form solutions for interest rate options obtain we propose an efficient algorithm to compute these prices an application using data on caps and floors shows that the model can capture very well the implied black spot volatility surface while simultaneously fitting the observed term structure c 2005 elsevier b v all rights reserved

the price of a smile hedging and spanning in option markets the volatility smile changed drastically around the crash of 1987 and new option pricing models have been proposed to accommodate that change deterministic volatility models allow for more flexible volatility surfaces but refrain from introducing additional risk factors thus options are still redundant securities alternatively stochastic models introduce additional risk factors and options are then needed for spanning of the pricing kernel we develop a statistical test based on this difference in spanning using daily s p 500 index options data from 1986 95 our tests suggest that both in and out of the money options are needed for spanning the findings are inconsistent with deterministic volatility models but are consistent with stochastic models that incorporate additional priced risk factors such as stochastic volatility interest rates or jumps article published by oxford university press on behalf of the society for financial studies in its journal the review of financial studies

can interest rate volatility be extracted from the cross section of bond yields most affine models of the term structure with stochastic volatility predict that the variance of the short rate should play a dual role in that it should also equal a linear combination of yields however we find that estimation of a standard affine three factor model results in a variance state variable that while instrumental in explaining the shape of the yield curve is essentially unrelated to garch estimates of the quadratic variation of the spot rate process or to implied variances from options we then investigate four factor affine models of the models tested only the model that exhibits unspanned stochastic volatility usv generates both realistic short rate volatility estimates and a good cross sectional fit our findings suggest that short rate volatility cannot be extracted from the cross section of bond prices in particular short rate volatility and convexity are only weakly correlated c 2009 elsevier b v all rights reserved

forecasting stock return variance toward an understanding of stochastic implied volatilities we examine the behavior of measured variances from the options market and the underlying stock market under the joint hypotheses that markets are informationally efficient and that option prices are explained by a particular asset pricing model forecasts from time series models of the stockreturn process should not have predictive content given the market forecast as embodied in option prices both in sample and out of sample tests suggest that this hypothesis can be rejected using simulations we show that biases inherent in the procedure we use to imply variances cannot explain this result thus we provide evidence inconsistent with the orthogonality restrictions of option pricing models that assume that variance risk is unpriced these results also have implicationsfor optimal variance forecast rules

testing the heath jarrow morton ho lee model of interest rate contingent claims pricing this paper presents empirical tests of the constant volatility version of the heath jarrow and morton model which is also the continuous time limit of the ho and lee model using a generalized method of moments gmm test on three years of daily data for eurodollar futures and futures options the model can be rejected for most subperiods various biases in the fitted option prices relative to the market prices are documented through a regression study the small sample properties and power of the gmm framework to this setting are also studied through simulations

estimation methods for stochastic volatility models a survey abstract although stochastic volatility sv models have an intuitive appeal their empirical application has been limited mainly due to difficulties involved in their estimation the main problem is that the likelihood function is hard to evaluate however recently several new estimation methods have been introduced and the literature on sv models has grown substantially in this article we review this literature we describe the main estimators of the parameters and the underlying volatilities focusing on their advantages and limitations both from the theoretical and empirical point of view we complete the survey with an application of the most important procedures to the s p 500 stock price index

statistical inference for random variance option pricing this article deals with the estimation of continuous time stochastic volatility models of option pricing we argue that option prices are much more informative about the parameters than are asset prices this is confirmed in a monte carlo experiment that compares two very simple strategies based on the different information sets both approaches are based on indirect inference and avoid any discretization bias by simulating the continuous time model we assume an ornstein uhlenbeck process for the log of the volatility a zero volatility risk premium and no leverage effect we do not pursue asymptotic efficiency or specification issues rather we stick to a framework with no overidentifying restrictions and show that given our option pricing model estimation based on option prices is much more precise in samples of typical size without increasing the computational burden

do bonds span the fixed income markets theory and evidence for unspanned stochastic volatility most term structure models assume bond markets are complete that is that all fixed income derivatives can be perfectly replicated using solely bonds however we find that in practice swap rates have limited explanatory power for returns on at the money straddles portfolios mainly exposed to volatility risk we term this empirical feature unspanned stochastic volatility usv while usv can be captured within an hjm framework we demonstrate that bivariate models cannot exhibit usv we determine necessary and sufficient conditions for trivariate markov affine systems to exhibit usv for such usv models bonds alone may not be sufficient to identify all parameters rather derivatives are needed

analysis of the term structure of implied volatilities from various empirical work it is well known that the volatility of asset returns changes over time this might be one of the reasons that implied volatilities differ for options that only differ in time to maturity we construct models for the relation between short and long term implied volatilities based on three different assumptions of stock return volatility behavior i e mean reverting garch and egarch models we test these relations on option price data and conclude that egarch gives the best description of asset prices and the term structure of options implied volatilities

effects of tractor ownership on returns to scale in agriculture evidence from maize in ghana abstract agricultural transformation process around the world has often accompanied the rise in returns to scale rts while tractor ownership is often associated with greater rts in agriculture whether the tractor ownership actually causes such increase in rts has not been formally tested in the literature we bridge this knowledge gap using a unique survey data of tractor owning farm households in ghana we find that owning tractors significantly increases the rts in maize production on the households largest mono cropped plot and weakens inverse relationship between land productivity and farm size this is partly achieved through the rise in the rts in tillage production the amount of tillage conducted rather than the rts in maize production given a fixed amount of tillage produced these sets of evidence are obtained by addressing jointly the multiple sources of endogeneity of tractor ownership tractor values tillage production and other inputs used

total factor productivity growth in agriculture a malmquist index analysis of 93 countries 1980 2000 in this paper we examine levels and trends in agricultural output and productivity in 93 developed and developing countries that account for a major portion of the world population and agricultural output we make use of data drawn from the food and agriculture organization of the united nations and our study covers the period 1980 2000 due to the non availability of reliable input price data the study uses data envelopment analysis dea to derive malmquist productivity indexes the study examines trends in agricultural productivity over the period issues of catch up and convergence or in some cases possible divergence in productivity in agriculture are examined within a global framework the paper also derives the shadow prices and value shares that are implicit in the dea based malmquist productivity indices and examines the plausibility of their levels and trends over the study period

the law of one price in data envelopment analysis restricting weight flexibility across firms abstract the law of one price loop states that all firms face the same prices for their inputs and outputs under market equilibrium taken here as a normative condition for efficiency prices this law has powerful implications for productive efficiency analysis which have remained unexploited thus far this paper shows how loop based weight restrictions can be incorporated in data envelopment analysis dea utilizing the relation between industry level and firm level cost efficiency measures we propose to apply a set of input prices that is common for all firms and that maximizes the cost efficiency of the industry our framework allows for firm specific output weights and for variable returns to scale and preserves the linear programming structure of the standard dea we apply the proposed methodology to the evaluation of the research efficiency of economics departments of dutch universities this application shows that the methodology is computationally tractable for practical efficiency analysis and that it helps in deepening the dea analysis

dynamic labor market competition and wage seniority abstract we design an overlapping generations model of the labor market experienced workers bear costs of switching employers whereas the segment for junior workers is horizontally differentiated the literature typically explains wage seniority premia with reference to productivity gains generated by the accumulation of worker experience or mechanisms associated with incomplete information in contrast this paper characterizes how the wage seniority premium depends on the relative intensities of competition in the markets for junior and senior workers in particular we show that a wage seniority premium may prevail even under circumstances where senior workers are less productive than junior workers

a test of dual labor market theory despite substantial differences in their views of the appropriate policy response to the existence of poverty neither the proponents of dual market theory nor its critics have proposed potentially conclusive tests of the dual market hypothesis this paper presents a test of the two central propositions of dual market theory 1 the existence of two distinct labor markets with different wage setting mechanisms and 2 the existence of barriers to mobility between the labor markets we find considerable support for both hypothesis estimation of a switching model of wage determination with unknown regimes yields two distinct wage equations the one which most workers are associated with closely resembles the standard human capital regression with significant returns to education and experience the other equation is flat with no returns to human capital these two equations resemble the predictions of dual market theory for the primary and secondary markets respectively further we present evidence that at least some non white workers are involuntarily confined to the secondary market this crowding of minority workers into the low wage labor market accounts for a substantial portion of white non white wage differences we interpret these results as providing empirical support for the dual market hypothesis and for recent theoretical work on efficiency wagemodels in addition combining the efficiency wage argument with the observation that much of the white non white wage difference is explained by the exclusion of non whites from the primary sector suggests an explanation for the persistance of wage differences this abstract was borrowed from another version of this item

improving envelopment in data envelopment analysis data envelopment analysis defines the relative efficiency of a decision making unit dmu as the ratio of the sum of its weighted outputs to the sum of its weighted inputs allowing the dmus to freely allocate weights to their inputs outputs however this measure may not reflect a dmu s true efficiency as some inputs outputs may not contribute reasonably to the efficiency measure traditionally to overcome this problem weights restrictions have been imposed this paper offers a new approach to this problem where dmus operate a constant returns to scale technology in a single input multi output context the approach is based on introducing unobserved dmus created by adjusting the output levels of certain observed relatively efficient dmus reflecting a combination of technical information of feasible production levels and the dm s value judgments its main advantage is that the information conveyed by the dm is local with reference to a specific observed dmu the approach is illustrated on a real life application 2003 elsevier b v all rights reserved

unspanned stochastic volatility and the pricing of commodity derivatives commodity derivatives are becoming an increasingly important part of the global derivatives market here we develop a tractable stochastic volatility model for pricing commodity derivatives the model features unspanned stochastic volatility quasi analytical prices of options on futures contracts and dynamics of the futures curve in terms of a low dimensional affine state vector we estimate the model on nymex crude oil derivatives using an extensive panel data set of 45 517 futures prices and 233 104 option prices spanning 4082 business days we find strong evidence for two predominantly unspanned volatility factors jel g13

affine model of inflation indexed derivatives and inflation risk premium abstract this paper proposes an affine based approach which jointly captures the nominal interest rate the real interest rate and the inflation risk premium to price inflation indexed derivatives including zero coupon inflation indexed swaps year on year inflation indexed swaps inflation indexed swaptions and inflation indexed caps and floors we provide an example and explain how to use traded zero coupon inflation indexed swap rates to estimate inflation risk premiums

the behavior of interest rates implied by the term structure of eurodollar futures this paper considers an equilibrium model of the term structure that is determined by two stochastic factors a short term interest rate and a target level to which the short rate is expected to revert a kalman filter technique that uses a time series cross section of eurodollar futures prices is developed to estimate the parameters of the model the term structures of spot libor and eurodollar futures volatility are compared to that predicted by the model the empirical results indicate that the two factor specification represents a significant improvement over its one factor version copyright 1996 by ohio state university press

expectation puzzles time varying risk premia and dynamic models of the term structure abstract linear projections of returns on the slope of the yield curve have contradicted the implications of the traditional expectations theory this paper shows that these findings are not puzzling relative to a large class of richer dynamic term structure models specifically we match all the key empirical findings reported by fama and bliss 1987 american economic review 77 4 680 692 and campbell and shiller 1991 review of economic studies 58 495 514 among others within large subclasses of affine and quadratic gaussian term structure models additionally we show that certain risk premium adjusted projections of changes in yields on the slope of the yield curve recover the coefficients of unity predicted by the models key to this matching are parameterizations of the market prices of risk that let the risk factors affect the market prices of risk directly and not only through factor volatilities the risk premiums have a simple form consistent with fama s findings on the predictability of forward rates and are also shown to be consistent with interest rate feedback rules used by a monetary authority in setting monetary policy

the importance of lifetime jobs in the u s economy though the u s labor market is justly notorious for high turnover and consequent high unemployment it also provides stable near lifetime employment to an important fraction of the labor force this paper investigates patterns of job duration by age race and sex with the following major conclusions 1 the typical worker today is holding a job which has lasted or will last about eight years over a quarter of all workers are holding jobs which will last twenty years or more sixty percent hold jobs which will last five years or more 2 the jobs held by middle aged workers with more than ten years of tenure are extremely stable over the span of a decade only twenty to thirty percent come to an end 3 among workers aged thirty and above about forty percent are currently working in jobs which eventually will last twenty years or more three quarters are in jobs which will last five years or more 4 the duration of employment among blacks is just as long as among whites even though the jobs held by blacks are worse in almost every other dimension they are no more unstable than those held by whites 5 women s jobs are substantially shorter than men s on the average only about a quarter of all women over the age of thirty are employed in jobs which will last over twenty years whereas over half of men over thirty are holding these near lifetime jobs this abstract was borrowed from another version of this item

incentive compatible long term contracts and job rationing this article presents a model in which markets for long term contractual employment coexist with spot markets for labor assuming the absence of third party enforcement wage contracts are required to be incentive compatible as a consequence contract wages yield higher expected utility to the worker than spot market wages so that in equilibrium contractual long term jobs are rationed

a non structural investigation of vix risk neutral density abstract we propose a non structural method to retrieve the risk neutral density rnd implied by options on the cboe volatility index vix the methodology is based on orthogonal polynomial expansions around a kernel density and yields the rnd of the underlying asset without the need for a parametric specification the classic family of laguerre expansions is extended to include the gig and the generalized weibull kernels we show that orthogonal polynomial expansions yield accurate approximations of the rnd of vix and they generally outperform commonly used non parametric methods when controlling for accuracy based on a panel of observed vix options we retrieve the variance swap term structure the time series of vvix the vix risk neutral moments and the volatility at risk which reveal a number of stylized facts on the rnd of vix

option values under stochastic volatility theory and empirical estimates abstract this paper numerically solves the call option valuation problem given a fairly general continuous stochastic process for return volatility statistical estimators for volatility process parameters are derived and parameter estimates are calculated for several individual stocks and indices the resulting estimated option values do not differ dramatically from black scholes values in most cases although there is some evidence that for longer maturity index options black scholes overvalues out of the money calls in relation to in the money calls

unspanned stochastic volatility in affine models evidence from eurodollar futures and options unspanned stochastic volatility usv refers to the inability of bonds to replicate volatility sensitive derivative securities affine term structure models require special restrictions on the parameters to exhibit usv we use a joint eurodollar futures and options data set to estimate affine three factor models with and without usv restrictions the unrestricted model captures prices of futures and options well option pricing errors are much larger in the usv model the usv model is rejected in favor of the unrestricted model based on the likelihood ratio and wald tests we use the implications of the unrestricted model as a benchmark for understanding the extant evidence that favors usv specifically we replicate extant tests in samples simulated from the unrestricted model we show that none of the existing findings contradict the model without usv restrictions

efficiency wage models of unemployment keynesian economists hold it to be self evident that business cycles are characterized by involuntary unemployment but construction of a model of the cycle with involuntary unemployment faces the obvious difficulty of explaining why the labor market does not clear involuntarily unemployed people by definition want to work at less than the going wage rate why don t firms cut wages thereby increasing profits

a parametric nonlinear model of term structure dynamics recent nonparametric estimation studies pioneered by ait sahalia document that the diffusion of the short rate is similar to the parametric function r superscript 1 5 estimated by chan et al whereas the drift is substantially nonlinear in the short rate these empirical properties call into question the efficacy of the existing affine term structure models and beg for alternative models which admit the observed behavior this article presents such a model our model delivers closed form solutions for bond prices and a concave relationship between the interest rate and the yields we show that in empirical analyses our model outperforms the one factor affine models in both time series as well as cross sectional tests article published by oxford university press on behalf of the society for financial studies in its journal the review of financial studies

a note on overemployment underemployment in labor contracts under asymmetric information abstract models of labor contracts under asymmetric information may predict either overemployment or underemployment this paper shows that this result depends crucially on whether or not leisure is a normal good if firms are risk neutral

monetary policy uncertainty and economic fluctuations uncertainty associated with the monetary policy transmission mechanism is a key driving force of business cycles to investigate this link we propose a new term structure model that allows the volatility of the yield curve to interact with macroeconomic indicators the data favors a model with two volatility factors that capture shortterm and long term monetary policy uncertainty increases in either of them lead higher unemployment rates but they interact with ination in opposite directions

productivity growth technical progress and efficiency change in industrialized countries this paper analyzes productivity growth in 17 oecd countries over the period 1979 1988 a nonparametric programming method activity analysis is used to compute malmquist productivity indexes these are decomposed into two component measures namely technical change and efficiency change we find that u s productivity growth is slightly higher than average all of which is due to technical change japan s productivity growth is the highest in the sample with almost half due to efficiency change jel c43 d24 in this paper we apply recently developed

implicit contracts incentive compatibility and involuntary unemployment this paper considers the enforceability of employment contracts when employees performance cannot be verified in court so that piece rate contracts are not legally enforceable part i shows that there exists a variety of self enforcing implicit contracts modelled as perfect equilibria in a repeated game and characterizes all the wage and performance outcomes that can be implemented implementation requires a strictly positive surplus from employment the form of the contract depending on how this surplus is divided between firm and employee piece rate contracts and contracts with an informally agreed bonus can be made self enforcing but the use of severance pay and bonding does not extend the set of implementable allocations the resulting contracts resemble actual labor contracts more than do the contracts in standard principal agent models part ii analyses market equilibrium with these contracts also modelled as perfect equilibria in a repeated game and shows that many such equilibria exist unfilled vacancies and unemployed workers can co exist despite the existence of contracts that are potentially mutually beneficial for those jobs that are filled any division of the potential surplus is possible so that the market can have at the same time involuntary unemployment and vacancies that are unfilled despite filled jobs earning positive profits as a criterion for selecting equilibria a notion of renegotiation proofness is applied then either all workers are employed or all jobs filled but any division of the potential surplus is still possible the paper explores what further restrictions on beliefs give rise to a walrasian outcome in which all the potential surplus goes to the short side of the market and to an efficiency wage type outcome in which the potential surplus goes to the long side

pricing interest rate derivatives a general approach the relationship between affine stochastic processes and bond pricing equations in exponential term structure models has been well established we connect this result to the pricing of interest rate derivatives if the term structure model is exponential affine then there is a linkage between the bond pricing solution and the prices of many widely traded interest rate derivative securities our results apply to m factor processes with n diffusions and l jump processes the pricing solutions require at most a single numerical integral making the model easy to implement we discuss many options that yield solutions using the methods of the article

unspanned stochastic volatility evidence from hedging interest rate derivatives most existing dynamic term structure models assume that interest rate derivatives are redundant securities and can be perfectly hedged using solely bonds we find that the quadratic term structure models have serious difficulties in hedging caps and cap straddles even though they capture bond yields well furthermore at the money straddle hedging errors are highly correlated with cap implied volatilities and can explain a large fraction of hedging errors of all caps and straddles across moneyness and maturities our results strongly suggest the existence of systematic unspanned factors related to stochastic volatility in interest rate derivatives markets