robust stochastic discount factors when the market is incomplete a new non redundant derivative security cannot be priced by no arbitrage arguments alone moreover there will be a multiplicity of stochastic discount factors and each of them may give a different price for the new derivative security this paper develops an approach to the selection of a stochastic discount factor for pricing a new derivative security the approach is based on the idea that the price of a derivative security should not vary too much when the payoff of the primitive security is slightly perturbed i e the price of the derivative should be robust to model misspecification the paper develops two metrics of robustness the first is based on robustness in expectation the second is based on robustness in probability and draws on tools from the theory of large deviations we show that in a stochastic volatility model the two metrics yield analytically tractable bounds for the derivative price as the underlying stochastic volatility model is perturbed the bounds can be readily used for numerical examination of the sensitivity of the price of the derivative to model misspecification

discrimination in the payment of full time wage premiums this study investigates how many hours must be worked per week in order for workers in different race and gender groups to receive a high hours full time wage premium an analysis of 1989 current population survey data shows that across occupations both white and black men received a full time wage premium for working at least 33 hours per week whereas white women had to work at least 37 hours and black women at least 39 hours to receive the premium controlling for occupation changes the threshold for black women to 33 hours but does not change the results for the other groups the authors find that the observed differences account for at most two percentage points of the wage differentials across race and gender

strong sustainability critical natural capital and the capability approach this article is an attempt to conceptually improve the notion of strong sustainability by creating a rapprochement between its core concept critical natural capital and the capability approach we first demonstrate that the capability approach constitutes a relevant framework for analysing the multiple links between human well being and critical natural capital second we demonstrate that the rapprochement between critical natural capital and the capability approach can form both the normative basis and the informational basis for a deliberative approach to human development which embraces a strong sustainability perspective this conceptual rapprochement as illustrated in our case study opens up avenues of research towards the practical implementation of human development projects from a strong sustainability perspective

optimal hedge ratio under a subjective re weighting of the original measure abstractin this article we study a risk minimizing hedge ratio with futures contracts where the risk of the hedged portfolio is measured through a spectral risk measure srm thus incorporating the degree of agent s risk aversion we empirically estimate the optimal hedge ratio ohr using a long time series of uk and us equity indices the eurusd and eurgbp exchange rates and four liquid commodities brent crude oil corn gold and copper to represent different asset classes comparing the results with common ohrs such as the minimum variance and the minimum expected shortfall we find that the agent s risk aversion has a material impact and should not be ignored in risk management

a search interpretation of male female wage differentials a general equilibrium search framework is used to examine the role of gender differences in labor market behavior patterns e g quit rates for personal reasons in determining gender wage differentials for samples of high school and college graduates from the national longitudinal survey of youth nlsy these behavioral patterns are found to be significantly different across the sexes and account for 20 30 of the wage differentials in particular they play a key role in explaining the male female wage differential that remains after controlling for the gender composition across occupations

the effect of asymmetries on optimal hedge ratios there is widespread evidence that the volatility of stock returns displays an asymmetric response to good and bad news this article considers the impact of asymmetry on time varying hedges for financial futures an asymmetric model that allows forecasts of cash and futures return volatility to respond differently to positive and negative return innovations gives superior in sample hedging performance however the simpler symmetric model is not inferior in a hold out sample a method for evaluating the models in a modern risk management framework is presented highlighting the importance of allowing optimal hedge ratios to be both time varying and asymmetric

managing exotic pests under uncertainty optimal control actions and bioeconomic investigations using a real options framework in continuous time we examine two problems associated with the management of exotic pests under uncertainty first we analyze the optimal timing of investing in a control action given fixed control costs we obtain a closed form solution for when to control an exotic pest whose density varies randomly second we define an analytical framework for finding the optimal expenditures for obtaining the relevant bioeconomic data our numerical results based on a wide range of bioeconomic parameters highlight the importance of accounting for uncertainty and irreversibility when developing simple rules to manage exotic pests

the place of the capability approach within sustainability economics the connections between the capability approach and sustainability economics have been explored recently i argue here that for engaging in a more substantive study of those connections we must first understand the place of the capability approach within the history of economic thought as a second stage of the revival of classical surplus theory once this is clear we can then use the capability approach in order to specify concepts such as well being surplus scarcity and sustainable reproduction which are essential for the development of sustainability economics

on arbitrage free pricing of interest rate contingent claims unlike most interest rate claim models the ho lee model utilizes full information on the current term structure unfortunately the model has a major deficiency in that negative interest rates can occur this article modifies the model such that interest rates are well behaved

bivariate garch estimation of the optimal commodity futures hedge six different commodities are examined using daily data over two futures contract periods cash and futures prices for all six commodities are found to be well described as martingales with near integrated garch innovations bivariate garch models of cash and futures prices are estimated for the same six commodities the optimal hedge ratio ohr is then calculated as a ratio of the conditional covariance between cash and futures to the conditional variance of futures the estimated ohrs reveal that the standard assumption of a time invariant ohr is inappropriate for each commodity the estimated ohr path appears non stationary which has important implications for hedging strategies

the relevance of epistemic analysis to sustainability economics and the capability approach abstract this paper considers how epistemic analyses birkin and polesie 2011 foucault 1970 foucault 1990a foucault 1990b may assist with the development of sustainability economics bartelmus 2010 baumgartner and quaas 2010a baumgartner and quaas 2010b and soderbaum 2011 and the capability approach ballet et al 2011 martins 2011 rauschmayer and lesmann 2011 scerri 2012 it was the french social theorist michel foucault 1926 1984 who coined the term episteme to refer to the possibility of knowledge that determines the development of thought and knowledge in a given period for foucault epistemes were the buried foundations of knowledge that his epistemic archaeology could unearth in 2007 foucault was identified as the most cited author of books in the humanities by thomson reuters isi web of science this paper begins with a brief definition and description of epistemic analyses a summary analysis of the modern episteme and neoclassical economics is then provided and this is followed by outline evidence for the emerging episteme finally the opportunity is considered for the emerging episteme to reinforce and enhance sustainability economics and the capability approach

a dynamic programming approach for pricing options embedded in bonds abstract we propose a dynamic programming dp approach for pricing options embedded in bonds the focus being on call and put options with advance notice an efficient procedure is developed for the cases where the interest rate process follows the vasicek cox ingersoll ross cir or generalized vasicek models our dp methodology uses the exact joint distribution of the interest rate and integrated interest rate at a future date conditional on the current value of the interest rate we provide numerical illustrations for the vasicek and cir models comparing our dp method with finite difference methods our procedure compares quite favorably in terms of both efficiency and accuracy an important advantage of the our dp approach is that it can be applied to more general models calibrated to capture the term structure of interest rates e g the generalized vasicek model

valuing managerial flexibility an application of real option theory to mining investments abstract the value of managerial flexibility is assessed using data on prices costs grades reserves ore extraction and metal output for a panel of canadian copper mines a real option model is estimated and solved for project and option values most empirical researchers i consider the initial investment decision but neglect flexible operation thereafter ii assume that price is stochastic but ignore cost and reserve uncertainty and iii model price as a nonstationary stochastic process the evolution of three state variables price cost and reserves is assessed here differences in assumptions compared to others are found to lead to large differences in estimated project and option values

a bivariate markov regime switching garch approach to estimate time varying minimum variance hedge ratios this article develops a new bivariate markov regime switching bekk generalized autoregressive conditional heteroscedasticity garch rs bekk garch model the model is a state dependent bivariate bekk garch model and an extension of gray s univariate generalized regime switching grs model to the bivariate case to solve the path dependency problem inherent in the bivariate regime switching bekk garch model we propose a recombining method for the covariance term in the conditional variance covariance matrix the model is applied to estimate time varying minimum variance hedge ratios for corn and nickel spot and futures prices out of sample point estimates of hedging portfolio variance show that compared to the state independent bekk garch model the rs bekk garch model improves out of sample hedging effectiveness for both corn and nickel data we perform white s 2000 data snooping reality check to test for predictive superiority of rs bekk garch over the benchmark model and find that the difference

the optimal value at risk hedging strategy under bivariate regime switching arch framework unlike the majority of other hedging literatures in which variance is taken as the risk indicator this article uses the value at risk var as the risk management tool of the hedged portfolio this article adopts a bivariate markov regime switching autoregressive conditional heteroscedastic swarch model to formulate the optimal var hedging strategy and then compares it with the other dynamic futures hedging strategies mentioned in the literature in hedging performance using taiwan stock exchange capitalization weighted stock index taiex futures data the in sample and out of sample results shows that when var is used as the criterion to measure the futures hedging effectiveness the performance of the dynamic hedging strategy is superior to that of the static hedging strategy and the performance of the optimal var hedging strategy is better than that of the minimum variance and mean variance hedging strategies besides from the standpoint that the volatility of hedge ratio and hedged portfolio var

the estimation of a joint wage hours labor supply model in this paper the standard cross sectional static model of labor supply is modified to make the wage endogenous and a joint wage hours model is estimated the econometric technique addresses the non linearity of the budget constraint by approximating the constraint by a series of discrete points the results show that the budget constraint is indeed nonlinear that hours affect the wage quadratically that true wage elasticities are lower as a result and that the model fits the hours distribution much better than the standard tobit model

hedging multiple price uncertainty in international grain trade commodity and freight futures contracts are analyzed for their effectiveness in reducing uncertainty for international traders a theoretical model is developed for a trader exposed to several types of risk ols hedge ratio estimation is compared to the sur and the multivariate garch methodologies explicit modeling of the time variation in hedge ratios via the multivariate garch methodology using all derivatives and taking into account dependencies between prices results in reductions in risk even after accounting for transaction costs results confirm that while the commodity futures contracts are important for hedging risk freight futures are a useful mechanism for reducing risk copyright 2000 oxford university press

insurance moral hazard and chemical use in agriculture this paper examines how crop insurance affects corn farmers fertilizer and pesticide use in the u s midwest crop insurance might be expected to affect chemical use because of moral hazard insured farmers may undertake riskier production than do uninsured farmers results suggest that insurance exerts considerable influence on corn farmers chemical use decisions those purchasing insurance applied significantly more nitrogen per acre 19 spent more on pesticides 21 and treated more acreage with both herbicides and insecticides 7 and 63 than did those not purchasing insurance these results suggest that both fertilizer and pesticides may be risk increasing inputs

crack spread hedging accounting for time varying volatility spillovers in the energy futures markets crude oil heating oil and unleaded gasoline futures contracts are simultaneously analysed for their effectiveness in reducing price volatility for an energy trader a conceptual model is developed for a trader hedging the crack spread various hedge ratio estimation techniques are compared to a multivariate garch model that directly incorporates the time to maturity effect often found in futures markets modelling of the time variation in hedge ratios via the multivariate garch methodology and thus taking into account volatility spillovers between markets is shown to result in significant reductions in uncertainty even while accounting for trading costs copyright 2002 john wiley sons ltd

on the evidence of a working spouse penalty in the managerial labor market this analysis of march 1993 current population survey data suggests that managers with working wives earn lower wages than their counterparts with non working wives the labor supply decisions of managers wives appear to be unaffected by that is exogenous with respect to their husbands wages in contrast there is evidence that the labor supply decisions of non managers wives are affected by their husbands wages and when the analysis takes account of that endogeneity it is found that non managers do not suffer a working spouse penalty the analysis also highlights some important issues related to the use of instrumental variables

market volatility and the dynamic hedging of multi commodity price risk commodity cash and futures prices experienced a severe boom and bust cycle between 2006 and 2009 increases in commodity price volatility have raised concerns about the usefulness of commodity futures and options as risk management tools dynamic hedging strategies have the potential to improve risk management when conditional co variances depart significantly from their unconditional long run counterparts and may be useful to decision makers despite their greater complexity and higher transaction costs we propose a nonparametric copula based generalized autoregressive conditional heteroscedastic npc garch approach to estimate time varying hedge ratios and evaluate the benefits of dynamic hedging during four sub periods between 2000 and 2011 using a stylized texas cattle feedlot management problem the npc garch approach allows for a flexible nonlinear and asymmetric dependence structure between cash and futures prices for different commodities we find that npc garch dynamic hedging performs bette

continuous time methods in finance a review and an assessment i survey and assess the development of continuous time methods in finance during the last 30 years the subperiod 1969 to 1980 saw a dizzying pace of development with seminal ideas in derivatives securities pricing term structure theory asset pricing and optimal consumption and portfolio choices during the period 1981 to 1999 the theory has been extended and modified to better explain empirical regularities in various subfields of finance this latter subperiod has seen significant progress in econometric theory computational and estimation methods to test and implement continuous time models capital market frictions and bargaining issues are being increasingly incorporated in continuous time theory the roots of modern continuous time methods in finance can be traced back to the seminal contributions of merton 1969 1971 1973b in the late 1960s and early 1970s merton 1969 pioneered the use of continuous time modeling in financial economics by formulating the intertemporal consumption and portfolio choice problem of an investor in a stochastic dynamic programming setting merton 1973b also showed how such a framework can be used to develop equilibrium asset pricing implications thereby significantly extending the asset pricing theory to richer dynamic settings and expanding the scope of applications of continuous time methods to study problems in financial economics 1 within a span of about 30 years from the publication of merton s inf luential papers continuous time methods have become an integral part of financial economics indeed in certain core areas in finance such as e g asset pricing derivatives valuation term structure theory and portfolio selection continuoustime methods have proved to be the most attractive way to conduct research and gain economic intuition the continuous time approach in these areas has produced models with a rich variety of testable implications the econometric theory for testing continuous time models has made rapid strides in the last decade and has thus kept pace with the impressive progress on the theoretical front one hopes that the actual empirical investigations and estimation using the new procedures will follow suit soon

an intertemporal general equilibrium model of asset prices this paper develops a continuous time general equilibrium model of a simple but complete economy and uses it to examine the behavior of asset prices in this model asset prices and their stochastic properties are determined endogenously one principal result is a partial differential equation which asset prices must satisfy the solution of this equation gives the equilibrium price of any asset in terms of the underlying real variables in the economy in this paper we develop a general equilibrium asset pricing model for use in applied research an important feature of the model is its integration of real and financial markets among other things the model endogenously determines the stochastic process followed by the equilibrium price of any financial asset and shows how this process depends on the underlying real variables the model is fully consistent with rational expectations and maximizing behavior on the part of all agents our framework is general enough to include many of the fundamental forces affecting asset markets yet it is tractable enough to be specialized easily to produce specific testable results furthermore the model can be extended in a number of straightforward ways consequently it is well suited to a wide variety of applications for example in a companion paper cox ingersoll and ross 7 we use the model to develop a theory of the term structure of interest rates many studies have been concerned with various aspects of asset pricing under uncertainty the most relevant to our work are the important papers on intertemporal asset pricing by merton 19 and lucas 16 working in a continuous time framework merton derives a relationship among the equilibrium expected rates of return on assets he shows that when investment opportunities are changing randomly over time this relationship will include effects which have no analogue in a static one period model lucas considers an economy with homogeneous individuals and a single consumption good which is produced by a number of processes the random output of these processes is exogenously determined and perishable assets are defined as claims to all or a part of the output of a process and the equilibrium determines the asset prices our theory draws on some elements of both of these papers like merton we formulate our model in continuous time and make full use of the analytical tractability that this affords the economic structure of our model is somewhat similar to that of lucas however we include both endogenous production and

time varying risk aversion an application to energy hedging abstract risk aversion is a key element of utility maximizing hedge strategies however it has typically been assigned an arbitrary value in the literature this paper instead applies a garch in mean garch m model to estimate a time varying measure of risk aversion that is based on the observed risk preferences of energy hedging market participants the resulting estimates are applied to derive explicit risk aversion based optimal hedge strategies for both short and long hedgers out of sample results are also presented based on a unique approach that allows us to forecast risk aversion thereby estimating hedge strategies that address the potential future needs of energy hedgers we find that the risk aversion based hedges differ significantly from simpler ols hedges when implemented in sample risk aversion hedges for short hedgers outperform the ols hedge ratio in a utility based comparison

a continuous time equilibrium model of forward prices and futures prices in a multigood economy abstract this paper is a theoretical investigation of equilibrium forward and futures prices we construct a rational expectations model in continuous time of a multigood identical consumer economy with constant stochastic returns to scale production using this model we find three main results first we find formulas for equilibrium forward futures discount bond commodity bond and commodity option prices second we show that a futures price is actually a forward price for the delivery of a random number of units of a good the random number is the return earned from continuous reinvestment in instantaneously riskless bonds until maturity of the futures contract third we find and interpret conditions under which normal backwardation or contango is found in forward or futures prices these conditions reflect the usefulness of forward and futures contracts as consumption hedges

european natural gas seasonal effects on futures hedging abstract this paper is the first to discuss the design of futures hedging strategies in european natural gas markets nbp ttf and zeebrugge a common feature of energy prices is that conditional mean and volatility are driven by seasonal trends due to weather demand and storage level seasonalities this paper follows and extends the ederington and salas 2008 framework and considers seasonalities in mean and volatility when minimum variance hedge ratios are computed our results show that hedging effectiveness is much higher when the seasonal pattern in spot price changes is approximated with lagged values of the basis futures price minus spot price this fact remains true for short a week and long one three and six months hedging periods furthermore volatility of weekly price changes also has a seasonal pattern and is higher in winter than in summer a simple volatility seasonal model that is based on sinusoidal functions on the basis improves the risk reduction obtained by strategies in which hedging ratios are estimated with linear regressions seasonal hedging strategies linear regression based strategies or even a naive position perform better than more sophisticated statistical methods

inequality sustainability and piketty s capital abstract in this article i address the implications of thomas piketty s book capital in the twenty first century for our understanding of inequality and sustainability drawing upon amartya sen s capability approach and the revival of classical political economy it brings i argue that piketty s contribution is a significant one which has the potential to lead economic analysis in a more fruitful direction but its potential becomes much greater if its empirical analysis is combined with the revival of classical political economy undertaken by sen and other authors rather than with marginalist theory

ecosystems strong sustainability and the classical circular economy abstract in this article i argue that notions such as ecosystem services and strong sustainability can be best understood and developed within the theoretical framework advanced by the classical political economists in which a circular conception of the economy is provided i also argue that the development of notions such as ecosystem services and strong sustainability has been constrained by the dominance of neoclassical economics which provides a linear conception of the economy and leads to an emphasis on weak sustainability which in turn springs from an emphasis on substitutability and aggregate capital when assessing the relevance of classical political economy for studying ecosystem services and strong sustainability i consider not only the contributions of the classical political economists but also more recent contributions which draw upon the classical perspective such as piero sraffa s and amartya sen s

spatial temporal model of insect growth diffusion and derivative pricing insect derivatives represent an important innovation in specialty crop risk management an active over the counter market in insect derivatives will require a transparent pricing method this paper develops an econometric model of the spatio temporal process underlying a particular insect population and develops a pricing model based on this process we show that insect derivatives can play an important risk management role in mitigating b tabaci whitefly damage in cotton beyond developing a new risk management instrument the key methodological contribution of this paper lies in pricing derivatives with stochastic properties in both space and time dimensions copyright 2008 oxford university press

basis convergence and long memory in volatility when dynamic hedging with futures abstractwhen market returns follow a long memory volatility process standard approaches to estimating dynamic minimum variance hedge ratios mvhrs are misspecified simulation results and an application to the s p 500 index document the magnitude of the misspecification that results from failure to account for basis convergence and long memory in volatility these results have important implications for the estimation of mvhrs in the s p 500 example and other markets as well

a utility based approach to energy hedging abstract a key issue in the estimation of energy hedges is the hedgers attitude towards risk which is encapsulated in the form of the hedgers utility function however the literature typically uses only one form of utility function such as the quadratic when estimating hedges this paper addresses this issue by estimating and applying energy market based risk aversion to commonly applied utility functions including log exponential and quadratic and we incorporate these in our hedging frameworks we find significant differences in the optimal hedge strategies based on the utility function chosen

employment contracts job search theory and labour turnover preliminary empirical results summary the empirical implications of a model in which a worker participates in a labour market in which a job offer consists of a wage hour pair are examined here hours are not freely adjustable and the wage rate is typically different from the marginal value of leisure a theoretical model is proposed some natural conjectures on effects of wage changes are shown not to hold and a preliminary empirical investigation based on denver income maintenance experiment data is undertaken the persistence of business cycles has led economists to consider explicitly potential sources of stickiness in wage and price adjustments particularly stickiness of nominal wages one explanation of slow adjustments of wages to shocks is that information arrives too rapidly with too much volatility or too much asymmetry for workers wages and hours to adjust so that the worker s wage is always equal to the value of his marginal product of labour and simultaneously to his marginal value of leisure time to avoid continuous adjustment workers and firms engage in implicit or explicit employment contracts azariadis 1975 modelled underemployment equilibria in a model with contracts baily 1977 studied a model in which certain fixed costs induce layoffs as firms respond to demand fluctuations more recent work by burdett and mortensen 1980 has considered the terms of equilibrium contracts in the labour market hart 1983 reviews the theory of optimal employment contracts emphasizing the role of asymmetric information fischer 1977a and implicitly phelps and taylor 1977 considered the effects of multiperiod contracts in dynamic macroeconomic models and found that certain policy neutrality results of the new classical macroeconomics could be invalidated under certain conditions it is worth mentioning at this point that keynes clearly recognized that the link between the real wage paid to workers and the value of their leisure time had to be broken before macropolicy of the keynesian type would be effective indeed keynesian macroeconomic problems arise because this link is broken keynes repeatedly refers to nominal wage bargains as providing the rigidity he wanted to model the importance of implicit or explicit employment agreements in economic theory has led to a small number of empirical studies which explicitly allow for divergence between the wage keynes 1936 ch 2 and 18 malinvaud 1977 provides a related discussion in some models contracts serve only to introduce a somewhat arbitrary rigidity barro 1977 notes that rational agents are unlikely to write contracts the provisions of which make all parties worse off see also the comment by fischer 1977b

public infrastructure investment interstate spatial spillovers and manufacturing costs effects of public infrastructure investment on the costs and productivity of private enterprises have proven difficult to quantify empirically one piece of this puzzle that has received little attention is spatial spillovers we apply a cost function model to 1982 1996 state level u s manufacturing data to untangle the private cost saving effects of inter and intrastate public infrastructure investment we implement two spatial adaptations including a spatial spillover index in the theoretical model and allowing for spatial autocorrelation in the stochastic structure recognizing such spillovers both increases the estimated magnitude and significance of cost savings from intrastate public infrastructure and augments these productive effects

estimation of the optimal futures hedge standard approaches to designing a futures hedge often suffer from two major problems first they focus only on minimizing risk so no account is taken of the impact on expected return second in estima ting the hedge ratio no allowance is made for time variation in the distribution of cash and futures price changes this paper describes a technique for estimating the optimal futures hedge that corrects these problems and illustrates its use in hedging treasury bonds with t bond futures copyright 1988 by mit press

parameter based decision making under estimation risk an application to futures trading this study shows how the standard portfolio model of futures trading should be modified when there is less than perfect information about the relevant parameters estimation risk the standard and the optimal decision rules for futures trading in the presence of estimation risk are compared and discussed an operational model of futures trading for use under estimation risk is advanced in the presence of relevant prior and sample information the model can be used to optimally blend both types of information many of the contributions of economic theory to the study of financial markets involve the use of parameters that are assumed known or estimable by the economic agents examples include the risk premium coefficient 18 and the security market lines that underlie the capital asset pricing model the volatility measures required for option pricing and the minimum variance hedge ratio and expected basis used to construct portfolios of futures contracts and cash positions generally it is left to practitioners to provide estimates of these parameters which are then directly substituted for the actual parameter values of the theoretical model whenever textbooks demonstrate how these parameters can be estimated there is usually a cookbook formula provided that requires some relatively straightforward analysis of the relevant data e g marshall 1989 chapters 6 and 7 cox and rubinstein 1985 chapter 6 the problems with the procedure described above are twofold first the theory has been slow to acknowledge that the practical application of the model almost always involves parameter estimates generally the additional risk of not knowing the true parameters is completely neglected second practitioners or the market participants will often have some type of nonsample information such as insider information or subjective priors that seems relevant for decision making however this potentially important information is ignored altogether when only sample data are used to obtain the parameter estimates

time horizon and the discount rate abstract we consider an economy a la lucas 1978 econometrica46 1429 1446 with a risk averse representative agent the exogenous growth rate of the economy follows a random walk we characterize the set of utility functions for which it is efficient to discount more distant cash flows at a lower rate the benchmark result is that when the growth rate is almost surely nonnegative the yield curve is decreasing if and only if relative risk aversion is decreasing with wealth relaxing the assumption on the absence of recession requires more restrictions on preferences such as increasing relative prudence journal of economic literature classification numbers d81 d91 q25 q28

issues of paradigm ideology and democracy in sustainability assessment does the challenge of sustainable development sd have implications for our approches to decision making and evaluation do we need specific sustainability assessment models sams and if so what

pricing weather derivatives this article presents a general method for pricing weather derivatives specification tests find that a temperature series for fresno ca follows a mean reverting brownian motion process with discrete jumps and autoregressive conditional heteroscedastic errors based on this process we define an equilibrium pricing model for cooling degree day weather options comparing option prices estimated with three methods a traditional burn rate approach a black scholes merton approximation and an equilibrium monte carlo simulation reveals significant differences equilibrium prices are preferred on theoretical grounds so are used to demonstrate the usefulness of weather derivatives as risk management tools for california specialty crop growers

the de merits of minimum variance hedging application to the crack spread we study the empirical performance of the classical minimum variance hedging strategy comparing several econometric models for estimating hedge ratios of crude oil gasoline and heating oil crack spreads given the great variability and large jumps in both spot and futures prices considerable care is required when processing the relevant data and accounting for the costs of maintaining and re balancing the hedge position we find that the variance reduction produced by all models is statistically and economically indistinguishable from the one for one naive hedge however minimum variance hedging models especially those based on garch generate much greater margin and transaction costs than the naive hedge therefore we encourage hedgers to use a naive hedging strategy on the crack spread bundles now offered by the exchange this strategy is the cheapest and easiest to implement our conclusion contradicts the majority of the existing literature which favours the implementation of garch based hedging strategies

3 d sustainability an approach for priority setting in situation of conflicting interests towards a sustainable development abstract this paper aims to provide a new approach to objectively assess hierarchies and priority setting in the relationship between environmental social and economic sustainability within sustainable development after a literature review several widely used conceptual figures diagrams describing this relationship were assessed using swot analyses in order to identify the major weaknesses in these pictorial descriptions based on the findings a new concept called 3 d sustainability has been developed and is presented visually as well as is described in the text this concept introduces and ranks criteria for the assessment of hierarchies within and conflicts of interests between social environmental and economic sustainability the three dimensions of sustainability these criteria are applied to several existing hierarchies and solutions to conflicts of interests based on the swot analyses the main shortcomings of the widely used conceptual figures were identified as 1 misinterpretation of embeddings 2 misjudgement of equity between the three dimensions of sustainability 3 a lack of expression of limitations and 4 lack of adequate decision support these shortcomings are overcome theoretically and in practice by 3 d sustainability a slightly more complex but conceptually richer figure than the widely used conceptual figures assessed in particular the shift of the burden of proof within the three sustainability dimensions is argued as a main solution the application of the criteria of 3 d sustainability to several real examples indicates its usefulness in decision support while justifying more sustainable hierarchies and solutions in the settlement of conflicts of interests within the three sustainability dimensions

pure martingale and joint normality tests for energy futures contracts abstract in this study we empirically analyze to see if the pure martingale hypothesis holds for three energy related commodities crude oil heating oil and natural gas we also test this hypothesis for five different hedging horizons 1 day 1 week 4 week 8 week and 12 week our empirical results show that the pure martingale hypothesis holds for all three commodities and all five horizons this implies that the expected return on futures contract can be ignored in determining the optimal hedge ratio we also test to see if the joint normality between futures and spot returns holds for the same three commodities and five hedging horizons we reject the joint normality hypothesis for all three commodities and five hedging horizons this implies that hedgers with different utility function have different optimal hedge ratios thus in general one needs to take into account of hedger s utility function when deriving optimal hedge ratio our results are robust to pre and post financial crisis as well as some other specifications considered in the paper

hedging effectiveness of the hedged portfolio the expected utility maximization subject to the value at risk approach multivariate volatilities and distribution play an important role in portfolio selection and can be used to calculate the value at risk var of a multiple asset financial position this study proposes a new expected utility maximization eum model that accounts for var eum model with a var constraint eum var additionally using the eum var model this study investigates the hedging effectiveness of short and long hedged portfolios constructed with multivariate generalized autoregressive conditional heteroscedasticity garch type models that feature level effects and multivariate normal and skewed distributions for stock indexes and their corresponding futures in the greater china region it is found that all else equal portfolios constructed using the multivariate skewed distribution are far more effective in hedging than those that rely on the other distributions and the effectiveness of hedged portfolios from the multivariate garch type models with level effects outperform those without level

optimal hedge ratios at the winnipeg commodity exchange multivariate garch models are employed to estimate time varying hedge ratios for three commodities traded on the winnipeg commodity exchange garch hedge ratios are shown to be superior to those based on the traditional regression approach to calculating the optimal hedge les ratios optimaux de comptant par rapport aux contrats a terme a la bourse de denrees de winnipeg l auteur emploie des modeles multivaries de type garch pour calibrer les ratios optimaux de comptant par rapport aux contrats a terme pour trois denrees transigees a la bourse des denrees de winnipeg ces ratios s averent superieurs a ceux qu on obtient par les methodes de regression traditionnelles

marital status and productivity evidence from personnel data although a robust wage premium for married men has been documented extensively in the labor economics literature prior studies have been hampered in testing competing explanations of the premium by a lack of data on worker productivity this study exploits a unique data set that contains job performance measures for employees of a large hierarchical organization the quasi longitudinal data track the marital status and job productivity including performance reviews and promotions of male naval officers in technical and managerial jobs compared with single men married men receive significantly higher performance ratings and are more likely to be promoted in estimates that control for selection arising from quit decisions the size of the marriage productivity effect falls but in most cases remains robust also based on supplementary tests selectivity arising from the decision to marry appears to explain only a small portion of the unadjusted marriage premium for navy officers although the existence of a wage premium for married men has been documented extensively in the labor economics literature the source of the premium has remained controversial one hypothesis attributes the wage differential to economies of scale and specialization within the household which provides incentives for additional investment in specific human capital by married men becker 1981 alternative hypotheses are that the marriage premium stems from employer favoritism or that more productive or higher earning men are selected into marriage the extensive empirical literature that has attempted to test the competing explanations has produced conflicting conclusions however one research approach to assess the effect of marital status that seldom has been implemented in the prior literature is to use data on the realized productivity of employees of a single firm this study uses administrative data on male employees of a large hierarchical organization to explore the effect of marital status on selected job performance measures the personnel database covers male u s naval officers and contains relatively detailed information on career performance including promotion outcomes and annual performance reviews the article seeks to shed light on the existence and magnitude of job productivity differentials between married and single males and to assess competing explanations for marriage related performance differentials navy personnel data are especially fertile for analyzing the effect of marital status on employee job productivity several performance measures are available for each individual and the indicators capture performance throughout an employee s tenure rather than at a single career point the design

do men whose wives work really earn less it is common knowledge among empirical labor economists that household status variables can enter significantly in wage equations in particular a substantial marital wage premium for men has been noted recently a series of articles in the management literature has argued that an even larger premium accrues to those married men whose wives do not work for pay single earner husbands our current study arises in response to perceived deficiencies in the conceptual framework and statistical methods used in these studies

on jump processes in the foreign exchange and stock markets exchange rates exhibit systematic discontinuities even after allowingfor conditional heteroskedasticity in the diffusion process the results are much more significant in theforeign exchange market than in the stock market which suggests differences in the structure of these markets finally this jump component is shown to explain some of the empirically observed mispricings in the currency options market the objective of this article is to analyze and compare the empirical distribution of returns in the stock market and in the foreign exchange market there are a number of reasons why a better understanding of the stochastic processes driving prices in these markets would be useful many financial models rely heavily on the assumption of a particular stochastic process while relatively little attention is paid to the empirical fit of the postulated distribution as a result models like option pricing models are applied indiscriminately to various markets such as the stock market and the foreign exchange market when the underlying processes may be fundamentally different the foreign exchange market for instance is characterized by active exchange rate man

the economic threshold with a stochastic pest population a real options approach using real options this paper formulates an optimal stopping model for applying pest control measures when the density of a pest population varies randomly a delay between successive pesticide applications is introduced to analyze the farmer s expected marginal cost of reentry this model is applied to the control of a foliar pest of apples via a pesticide and solved numerically a sensitivity analysis shows that the pest density that should trigger pesticide use can vary significantly with the pest density volatility incorporating pest randomness into simple decision rules may thus help better manage the chemicals applied to soils and crops

a note on sustainability economics and the capability approach sustainability economics attempts to reconcile efficiency criteria with those of social justice in a context of environmental concern this article aims at highlighting the fact that the capability approach offers an interesting perspective for the foundation of sustainability in economics it primarily focuses on the major role that freedom brings as a normative basis for well being and adds new insights for our understanding of human and environment relationship through the study of the constraints and opportunities that affect the individual the final section of this article asks us to reconsider our nature conservation choices by acknowledging the restrictive impact that they have on individual freedoms

an examination of dynamic hedging abstract i compare garch modeled dynamic hedging strategies with traditional ols modeled strategies to determine which perform better i find that dynamic hedging reduces risk more than static hedging but only slightly this is consistent with some previous findings that more complex hedging methods may not improve the performance much briys and solnik s 1992 static comparison of the macroeconomic and asset specific components of the hedge ratio is extended to a dynamic setting to examine how the relative importance of these two components evolves through time cointegrating relationship between the spot and forward rates in the macroeconomic component is also considered but its effect is minimal the asset specific component has effect in the out of sample period especially under dynamic strategies and under short term hedging horizons

tax credits labor supply and child care we explore the impact of the child care tax credit in the u s income tax system on the labor supply decisions of married women with young children by incorporating the cost of child care into a st

the definition of part time employment a switching regression model with unknown sample selection rejecting the standard less than thirty five hours per week categorization of part time workers this paper offers an empirically justified definition of the part time employed the definition is based on the distinction through wage payments that employers make between a high hours full time and a low hours part time group of workers a switching regression model of wage equations with deterministic but unknown sample selection is estimated resulting in a significant split between high hours and low hours workers that is higher than the standard definition wage differentials are calculated and decomposed and estimates from the structural choice model are presented copyright 1991 by economics department of the university of pennsylvania and the osaka university institute of social and economic research association

optimal hedge ratio estimation and hedge effectiveness with multivariate skew distributions this article proposes to use the three multivariate skew distributions generalized hyperbolic distribution multivariate skew normal distribution and multivariate skew student t distribution for estimating the minimum variance hedge ratio in a dynamic setting three criteria for measuring hedge effectiveness are employed hedging instrument effectiveness overall hedge effectiveness and relative to optimal hedge ratio effectiveness rhre three portfolios of spot and futures series are formed for empirical analysis the outcomes confirm that the three multivariate skew distributions are more helpful in deciding the minimum variance hedge ratio especially the generalized hyperbolic distribution than the symmetrical normal and student t distributions this outperformance is significant especially at critical market moments and it is indicated by three hedge effectiveness measures this advantage is held without the cost of lowering portfolio return in addition there is speculation possibility exist

single factor heath jarrow morton term structure models based on markov spot interest rate dynamics this paper considers the class of heath jarrow morton term structure models where the spot interest rate is markov and the term structure at time t is a function of time maturity and the spot interest rate at time t a representation for this class of models is derived and i show that the functional forms of the forward rate volatility structure and the initial forward rate curve cannot be arbitrarily chosen i provide necessary and sufficient conditions indicating which combinations of these functional forms are allowable i also derive a partial differential equation representation of the term structure dynamics that does not require explicit modeling of both the market price of risk and the drift term for the spot interest rate process using the analysis presented in this paper a class of intertemporal term structure models is derived

futures cross hedging with a stationary basis when managing risk frequently only imperfect hedging instruments are at hand we show how to optimally cross hedge risk when the spread between the hedging instrument and the risk is stationary for linear risk positions we derive explicit formulas for the hedge error and for nonlinear positions we show how to obtain numerically efficient estimates finally we demonstrate that even in cases with no clear cut decision concerning the stationarity of the spread it is better to allow for mean reversion of the spread rather than to neglect it

estimating the optimal hedge ratio in the presence of potential unknown structural breaks we propose a new approach in the estimation of the optimal hedge ratio that allows the hedge ratio to vary over time but without the necessity of frequently rebalancing the portfolio we apply this in the context of the us and uk equity markets using weekly spot share prices and future share prices during the period 5 january 1999 to 29 september 2009 our method is to test for cointegration in the presence of two potentially unknown structural breaks by determining the timing of each via the underlying data the empirical findings reveal that the spot and future prices are strongly cointegrated in each market the estimated parameters disclose that the optimal hedge ratio is not constant in case of the us and the uk we find one negative and one positive shift in the optimal hedge ratio in the us however we find only one significant and positive shift in the optimal hedge ratio in the uk the implication of these findings from the perspective of both investors as well as policy makers is elaborated on

optimal dynamic hedging portfolios and the currency composition of external debt abstract we present a model which shows that the currency composition of a country s external debt can serve as a hedging instrument against changes in exchange rates and commodity prices because our model permits the second moments to change through time we get a sequence of optimal dynamic hedging portfolios which can be estimated with a multivariate generalized autoregressive conditional heteroskedasticity garch model to illustrate the usefulness of the technique we apply it to indonesia and it is found as expected that indonesia s optimal debt portfolio consists of a much larger proportion of us dollars and a much smaller proportion of japanese yen than they have in their current debt portoflio

labor supply preferences hours constraints and hours wage tradeoffs in a labor market with tied hours wage packages and wage dispersion for a particular type of job constrained workers may be willing to sacrifice wage gains for better hours when changing jobs likewise workers may accept jobs offering undesirable hours only if the associated wage gains are large we investigate this issue empirically by examining whether overemployment and underemployment on the initial and new job affects the relation between hours changes and wage changes for quitters our results generally support the view that an individual requires compensation to work in a job that given the individual s particular preferences offers unattractive hours

a markov model of switching regime arch in this article i present a new approach to model more realistically the variability of financial time series i develop a markov arch model that incorporates the features of both hamilton s switching regime model and engle s autoregressive conditional heteroscedasticity arch model to examine the issue of volatility persistence in the monthly excess returns of the three month treasury bill the issue can be resolved by taking into account occasional shifts in the asymptotic variance of the markov arch process that cause the spurious persistence of the volatility process i identify two periods during which there is a regime shift the 1974 2 1974 8 period associated with the oil shock and the 1979 9 1982 8 period associated with the federal reserve s policy change the variance approached asymptotically in these two episodes is more than 10 times as high as the asymptotic variance for the remainder of the sample i conclude that regime shifts have a greater impact on the properties of the data and i ca

moment based estimation of stochastic volatility abstract this paper makes use of the distributional information contained in high frequency data to test for the specification of the functional form of the volatility process within the class of stochastic volatility models it s calculus is implemented in order to obtain the first and second conditional moment of the driving stochastic differential equation for the volatility process these analytical expressions are augmented by their lag and lag squared and are used to form the corresponding gmm estimator the base case stochastic volatility model is extended to allow for the leverage effect and jumps in returns empirical estimation confirms the presence of fast mean reversion in volatility and jumps in returns for the 5 min s p 500 stock market index further estimation results also seem to indicate the presence of jumps in the volatility process that are correlated to the jumps in returns

ends in view the capabilities approach in ecological sustainability economics while traditional scientific endeavor seeks to avoid the problem ecological economics and the broader emergent field of sustainability economics e se are explicitly grounded in a particular ethico moral assertion one that defines sustainability as a normative notion about the way how humans should act towards nature and how they are responsible towards one another and future generations baumgartner and quaas 2010 p 445 thus e se is neither a purely positive science nor is it a purely normative endeavor but it is what has been called relevant science baumgartner and quaas 2010 p 447 a key objective of e se is therefore said to be to study how ecosystems and human activity interrelate in terms that extend beyond functional and descriptive analysis of this interrelationship and towards explicitly incorporating this normative vision the result that is aimed for is a discipline that is constituted as the best possible approach to the science and management of sustainability

the classical circular economy sraffian ecological economics and the capabilities approach abstract here i provide some further elaborations on the idea of a classical circular economy and its articulation with the capabilities approach this enables addressing some important questions raised by yoann verger 2017 when commenting on the idea of a classical circular economy as outlined in martins 2016 while advancing the basis for a sraffian ecological economics to understand the connections between sraffa s economic theory and the classical circular economy discussed by verger 2017 an essential aspect to be addressed here is sraffa s interpretation of the classical conception of the wage which can be fruitfully addressed in terms of the capabilities approach as suggested by vivian walsh 2000

another look at models of the short term interest rate the short term rate of interest is fundamental to much of theoretical and empirical finance yet no consensus has emerged on the dynamics of its volatility we show that models which parameterize volatility only as a function of interest rate levels tend to over emphasize the sensitivity of volatility to levels and fail to model adequately the serial correlation in condi tional variances on the other hand serial correlation based models like garch models fail to capture adequately the relationship between interest rate levels and volatility we introduce and test a new class of models for the dynamics of short term interest rate volatility which allows volatility to depend on both interest rate levels and information shocks two important conclusions emerge first the sensitivity of interest rate volatility to interest rate levels has been overstated in the literature while this relationship is important adequately modeling volatility as a function of unexpected information shocks is also important sec ond we conclude that the volatility processes in many existing theoretical models of interest rates are misspecified and suggest new paths toward improving the theory

general equilibrium pricing of options on the market portfolio with discontinuous returns when the price process for a long lived asset is of a mixed jump diffusion type pricing of options on that asset by arbitrage is not possible if trading is allowed only in the underlaying asset and a risk less bond using a general equilibrium framework we derive and analyze option prices when the underlying asset is the market portfolio with discontinuous returns the premium for the risk of jumps and the diffusion risks forms a significant part of the prices of the options in this economy an attempted replication of call and put options by the black scholes type of trading strategies may require substantial infusion of funds when jumps occur we study the cost and risk implications of such dynamic hedging plans article published by oxford university press on behalf of the society for financial studies in its journal the review of financial studies

the effect of barge and ocean freight price volatility in international grain markets this paper looks at the potential role of time varying volatility of mississippi river barge and ocean freight prices on commodity prices in illinois at the us gulf and in rotterdam using a vector error correction garch in mean model the model is used to infer the extent to which transportation price risk affects price dynamics in international grain markets results from a simulation exercise indicate that both barge and ocean price volatility influence grain prices but barge price volatility tends to have a greater impact on grain prices and marketing margins than that arising from ocean price volatility consistent with most studies that evaluate the role of risk in marketing channels results here suggest that a reduction in barge rate risk would reduce marketing margins between illinois and the us gulf and between the us gulf and rotterdam the existence of an ocean freight futures contract coupled with the lack of a futures contract for barge rates may be partially responsible for the finding that barge rates have a significant influence on grain prices and contribute most to wide marketing margins found throughout the international grain marketing system

managing economic risk in value based marketing of fed cattle this research investigates optimal price risk management strategies for fed cattle producers engaged in grid pricing stochastic simulation is used to determine optimal hedge ratios for fed cattle priced on a live weight basis or on a series of grids that vary in terms of premium discount structure as well as base price results indicate that the optimal hedging strategy is greatly affected by the base price used in a particular grid this has significant implications for pricing efficiency in the cattle market base prices that are linked more closely with downstream markets offer the potential to improve pricing efficiency however the risk associated with these prices is difficult to manage effectively with existing futures instruments

comparative dynamics of an equilibrium intertemporal asset pricing model this paper uses recursive competitive theory to develop a general equilibrium asset pricing model in this framework all prices and rates of return are endogenously determined thus enabling us to analyze the effects of changes in preferences technological uncertainty and expectations on the structure of security prices in particular we focus on how the market risk premium varies with changes in the underlying economic environment an issue which other asset pricing models have chosen not to address

unraveling the veil of fuzziness a thick description of sustainability economics this article provides a thick description geertz 1973 of sustainability economics baumgartner and quaas 2010a b have proposed as an alternative to ecological economics the new field of sustainability economics which has triggered various replies the purpose here is to order and to review these contributions building upon a literature review of sustainability economics the paper argues that the concept currently has more of a fuzzy and declamatory character the rhetoric mccloskey 1998 of sustainability economics contains general issues of sustainability economics externalities and the capability approach the article argues that it is currently not clear how the solutions for science and policy proposed by sustainability economics differ from those of ecological economics efforts should be directed towards further development of the theory and the operationalization of sustainability principles the systemic view of co evolutionary development social learning and sustainability economics normative underpinning merits more consideration in the debate about sustainability economics