effects of economic shocks on children s employment and schooling in brazil abstract this paper uses longitudinal employment survey data to analyze the impact of household economic shocks on the schooling and employment transitions of young people in metropolitan brazil the paper uses data on over 100 000 children ages 10 16 from brazil s monthly employment survey pme from 1982 to 1999 taking advantage of the rotating panels in the pme we compare households in which the male household head becomes unemployed during a four month period with households in which the head is continuously employed probit regressions indicate that an unemployment shock significantly increases the probability that a child enters the labor force drops out of school and fails to advance in school the effects can be large implying increases of as much as 50 in the probability of entering employment for 16 year old girls in contrast shocks occurring after the school year do not have significant effects suggesting that these results are not due to unobserved characteristics of households that experience unemployment shocks the results suggest that some households are not able to absorb short run economic shocks with negative consequences for children

banking technology and the existence of a consistent output aggregate abstract this paper addresses the question of the existence of a consistent output aggregate in banking specific necessary and sufficient conditions for output aggregation are developed and tested in the context of a second order approximation to any arbitrary multi product bank cost function the analysis provides evidence that a composite aggregate measure of output fails to provide a proper representation of banking technology and therefore previous studies that used aggregate output measures may well be subject to specification errors

technology adoption under production uncertainty theory and application to irrigation technology we propose a theoretical framework to analyze the conditions under which a farmer facing production uncertainty due to a possible water shortage and incomplete information will adopt a more efficient irrigation technology a reduced form of this model is empirically estimated using a sample of 265 farms located in crete greece the empirical results suggest that farmers choose to adopt the new technology in order to hedge against production risk in addition we show that the farmer s human capital also plays a significant role in the decision to adopt modern more efficient irrigation equipment

industrial structure and child labor evidence from the brazilian population census abstractthis paper uses micro data from the 1980 1991 and 2000 population censuses to investigate the role of changes in the industry mix in accounting for the differential trends in the incidence of child work ages 10 15 across brazilian states we find that exogenous compositional changes account for around 20 of the observed fall in child employment in rural areas

the nonparametric risk adjusted efficiency measurement an application to taiwan s major rural financial intermediaries in this article a nonparametric approach is used to incorporate risk into the measurement of technical efficiencies of the major financial intermediaries in rural taiwan risk is treated as a joint but undesirable output given the fact that various regulatory actions may prevent its free disposability three risk indicators nonperforming loans allowance for loan losses and risky assets are employed alternatively in the empirical work results suggest that all three risk constraints are binding regulations on controlling risky assets and loan loss reserves are effective but more burdensome than those on controlling loan quality

does child labor decline with improving economic status between 1993 and 1997 child labor in vietnam declined by nearly 30 percent while the country s gdp grew by nearly 9 percent per year on average using a simple nonparametric decomposition i investigate the relationship between improvements in per capita expenditure and child labor with a panel data set that spans this episode of growth in vietnam improvements in per capita expenditure can explain 80 percent of the decline in child labor that occurs in households whose expenditures improve enough to move out of poverty this finding suggests a previously undocumented role for economic growth in the amelioration of child labor

weak disposability in nonparametric production analysis reply to fare and grosskopf fare and grosskopf this issue claim that a single abatement factor suffices for modeling weak disposability in nonparametric production models and that the kuosmanen 2005 technology that uses multiple abatement factors is larger than necessary this article demonstrates by a numerical example that a single abatement factor does not suffice to capture all feasible production plans and that its use leads to the violation of convexity one of the maintained assumptions of the model we also prove that the kuosmanen technology is the correct minimum extrapolation technology under the stated axioms

comparison among u s industrial sectors by dea environmental assessment equipped with analytical capability to handle zero or negative in production factors abstract a green image is recently an important component of corporate sustainability in modern business by extending the two previous works i e wang et al 2014 sueyoshi and wang 2014a this study discusses a new use of data envelopment analysis dea for environmental assessment by incorporating an analytical capability to handle zero and or negative in a data set the proposed approach provides us with not only new quantitative assessment on unified operational and environmental performance of firms but also information regarding how to invest for eco technology innovation for abating an amount of their industrial pollutions according to the previous studies the energy industry is an attractive investment target if desirable outputs are measured by return on assets roa as a short term concern and an amount of co 2 emission reduction the selection on a desirable output combination is important in understanding the corporate sustainability of the energy industry because it is the largest emitter among seven industry sectors examined in the previous studies however if the roa is replaced by a corporate value measured by tobin s q ratio as a long term concern the energy industry is not so attractive because it uses a very large production process so that green investment does not immediately increase the corporate value an empirical problem of these previous studies is that they have investigated only successful companies with positive roa or tobin s q ratios the analytical feature clearly indicates a methodological drawback of their studies in contrast this study pays attention to both successful companies with positive net incomes and unsuccessful companies with negative net incomes so being able to measure all aspects of their performance in a short term concern this study finds that the energy industry exhibits a high level of potential on green investment however the energy industry may be not attractive even in the short term concern i e net income partly because governmental regulations on their operation and pollution prevention efforts are stricter than the other industrial sectors this result may be seemingly inconsistent with wang et al 2014 rather the result indicates that successful energy firms can attain the corporate sustainability by investing eco technology innovation but unsuccessful ones cannot attain the sustainability even in the short term concern because they do not have large capital accumulation for eco technology investment whose importance has been first discussed by sueyoshi and goto 2010a in other words the eco technology investment for enhancing a high level of corporate sustainability depends upon an amount of net income generated by each energy firm

what went wrong the erosion of relative earnings and employment among young black men in the 1980s this paper shows a widening in black white earnings and employment gaps among young men from the mid 1970s through the 1980s earnings gaps increased most among college graduates and in the midwest while gaps in employment population rates grew most among dropouts we attribute the differential widening to shifts in demand for subgroups due to shifting industry and regional employment the falling real minimum wage and deunionization the growing supply of black to white workers that was marked among college graduates and to increased crime among dropouts the different factors affecting subgroups highlight the economic diversity of black americans

environmental efficiency with multiple environmentally detrimental variables estimated with sfa and dea abstract the objective of this paper is to estimate comprehensive environmental efficiency measures for dutch dairy farms the environmental efficiency scores are based on the nitrogen surplus phosphate surplus and the total direct and indirect energy use of an unbalanced panel of dairy farms we define environmental efficiency as the ratio of minimum feasible to observed use of multiple environmentally detrimental inputs conditional on observed levels of output and the conventional inputs we compare two methods for the calculation of efficiency namely stochastic frontier analysis sfa and data envelopment analysis dea this paper reveals the strengths and weaknesses for estimating environmental efficiency of the methods applied both sfa and dea can estimate environmental efficiency scores the mean technical efficiency scores output oriented sfa 89 dea 78 and the mean comprehensive environmental efficiency scores sfa 80 dea 52 differ between the two methods sfa allows hypothesis testing and the monotonicity hypothesis is rejected for the specification including phosphate surplus dea can calculate environmental efficiency scores for all specifications because regularity is imposed in this method

ecological modernization in the electrical utility industry an application of a bads goods dea model of ecological and technical efficiency abstract newly developed data envelopment analysis techniques permit simultaneous consideration of good and bad outputs in evaluating efficiency we use these techniques to determine joint ecological and technical efficiencies of the 437 largest fossil fueled electricity generating plants in the united states utilizing the epa s e grid and clean air markets databases and drawing on ecological modernization theory we evaluate whether innovations in organizational practices and technological solutions help achieve joint technical and environmental performance efficiencies

dynamic multiproduct optimal hedging in the soybean complex do time varying correlations provide hedging improvements optimal multiproduct time varying hedge ratios are determined for a soybean complex and their risk mitigating impact is contrasted over single commodity time varying and naive hedge ratios a parsimonious regime switching dynamic correlation model is employed with the estimated dynamic correlation matrix among prices varying between two different levels and the time varying correlations being applied to the multiproduct setting findings obtained are three fold first there is significant evidence that estimated simultaneous correlations among different commodities prices e g soybean spot and soybean meal futures attain different values along the time series second there is a substantial reduction in margin variance provided by the optimal multiproduct time varying hedge ratios over single time varying and naive hedge ratios for both in and out of sample data third average optimal multiproduct time varying hedge ratios for soybean and soybean meal 0 82 and 0 74 respectively for out of

a decomposition of profit loss under output price uncertainty in this paper firm profit loss is decomposed as the sum of two terms related to the output price uncertainty price expectation error and risk preference plus one extra term expressing technical inefficiency we then describe the implementation of our theoretical model in a robust data envelopment analysis dea framework which allows an effective and separate estimation of each term of the decomposition in addition we offer an operational tool to reveal producers risk preferences a 2009 database of french fattening pig farms is used as an illustration our results indicate that risk preference and technical inefficiency are the main sources of profit loss

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

testing the stochastic structure of production a flexible moment based approach conventional production function specifications are shown to impose restrictions on the probability distribution of output that cannot be tested with the conventional models these restrictions have important implications for firm behavior under uncertainty a flexible representation of a firm s stochastic technology is developed based on the moments of the probability distribution of output these moments are a unique representation of the technology and are functions of inputs large sample estimators are developed for a linear moment model that is sufficiently flexible to test the restrictions implied by conventional production function specifications the flexible moment based approach is applied to milk production data the first three moments of output are statistically significant functions of inputs the cross moment restrictions implied by conventional models are rejected

fungicide use under risk in swiss wheat production abstract the short run effects of fungicide application on economic risk and the effects of risk on fungicide use in swiss wheat production are empirically explored a quadratic production function model is developed with the help of the moment based approach marginal contributions of fungicides representing controlled inputs and of rain representing uncontrolled inputs to the variances of yield and revenue are analyzed it is not possible to show risk reducing effects of fungicides on yield or revenue at low rain quantities during the vegetation period fungicides have a statistically significant risk increasing effect on revenue increasing risk leads swiss wheat growers to use more fungicide this increase is statistically significant at higher levels of revenue for example when risk is doubled fungicide inputs are raised by 44 at the highest revenue quartile

the economics of child labor if child labor as a mass phenomenon occurs not because of parental selfishness but because of the parents concern for the household s survival the popular argument for banning child labor loses much of its force however this assumption about parental decision making coupled with the assumption of substitutability in production between child and adult labor could result in multiple equilibria in the labor market with one equilibrium where children work and another where adult wage is high and children do not work the paper establishes this result and discusses its policy implications copyright 1998 by american economic association

productivity change in taiwan s farmers credit unions a nonparametric risk adjusted malmquist approach this article proposes an extended three stage dea methodology similar to fried et al 2002 to improve the measurement of productivity growth when the assumption of free disposability of undesirable output does not apply a directional distance function is used to construct adjusted malmquist luenberger productivity indexes which simultaneously account for the impacts of undesirable outputs environmental variables and statistical noise panel data for 263 farmers credit unions fcus in taiwan covering the 1998 2000 periods are employed to illustrate the advantages of this method on average the productivity of taiwan s fcus is found to have deteriorated over the 1998 2000 period although an improvement in efficiency has been observed the major reason for the deterioration is found to be due to the regression of technology

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

a literature study for dea applied to energy and environment abstract this study systematically summarizes previous research efforts on data envelopment analysis dea applied to energy and environment in the past four decades including concepts and methodologies on dea environmental assessment industrial developments are very important for all nations in terms of their economic prosperities a problem is that the development produces various pollutions on air water and other types of contaminations all of which are usually associated with our health problems and climate changes thus it is necessary for us to consider how to make a balance between economic success and pollution mitigation to maintain a high level of social sustainability in the world it is widely considered that dea is one of the methodologies to examine the level of sustainability this study examines a recent research trend on dea applications from 1980s to 2010s nowadays many researchers have paid serious attention on how to combat various difficulties in the areas of energy and environment as a result the number of articles on dea applications on energy and environment has dramatically increased particularly after 2000s however it is true that dea has strengths and drawbacks in the applications therefore it is very important for us to carefully use dea for guiding large policy issues and business strategies such as the global warming and climate change an underlying premise of this study is that technology innovation in engineering and natural science may solve various problems by linking it with political and managerial efforts the use of dea provides a methodological linkage among them so enhancing the practicality in mitigating problems due to climate change and environmental pollutions this literature study along with a summary on conceptual and methodological developments provides us with guidelines for our future research works on dea on energy and environment issues

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

the dominance of inefficiencies over scale and product mix economies in banking abstract this study measures and analyzes inefficiencies for all u s banks in 1984 inefficiencies are measured relative to a thick frontier cost function and are found to dominate measured scale and product mix economies most inefficiencies are operational in nature involving the overuse of physical inputs rather than financial involving overpayment of interest also technical inefficiencies proportionate overuse of all inputs dominate allocative inefficiencies improper mix of inputs these results suggest that competitive pressures in banking from deregulation will be focused primarily on banks that do not control costs rather than on those of a particular size or product mix

co2 and energy efficiency of different heating technologies in the dutch glasshouse industry this paper uses data envelopment analysis tocompute input based technical efficiencymeasures and co2 and energy technicalefficiency of specialised vegetable firms inthe netherlands over the period 1991 1995 input based scale efficiency is also calculatedfor each firm these efficiency measures aregenerated for firms with different heatingtechnologies the empirical results indicatethat firms use energy quite efficiently and areless efficient in terms of co2 emissions differences in co2 energy efficiencyacross different technologies are not statistically significant in particular firms using traditional heating technologiesare less efficient in terms of co2 scaleadjustments can provide an importantcontribution to further efficiencyimprovements

is child labor inefficient we build a model of child labor and study its implications for welfare we assume that there is a trade off between child labor and the accumulation of human capital even if parents are altruistic and child labor is socially inefficient it may arise in equilibrium because parents fail to fully internalize its negative effects this occurs when bequests are zero or when capital markets are imperfect we also study the effects of a simple ban on child labor and derive conditions under which it may be pareto improving in general equilibrium we show that the implications of child labor for fertility are ambiguous

the technical efficiency of us banks abstract the paper uses a non parametric frontier approach to measure the technical efficiency of a sample of u s banks the results indicate that these banks could have produced the same level of output with only 70 of the inputs actually used in addition most of this inefficiency is due to pure technical inefficiency wasting inputs rather than scale inefficiency operating at non constant returns to scale finally regression analysis indicates that the technical efficiency of the banks is positively related to size negatively related to product diversity and not at all related to the extent to which branch banking is allowed

asymmetry partial moments and production risk partial moment functions are proposed as a flexible way to characterize and estimate asymmetric effects of inputs on output distributions methods for econometric estimation of partial moment functions and tests for input symmetry and location scale distributions are presented a monte carlo study demonstrates properties of proposed tests a study of ecuadorian potato production illustrates the methods hypotheses of input symmetry and location scale are rejected a risk value model based on partial moments implies that fertilizer is risk increasing and fungicides and labor are risk reducing in potato production whereas an expected utility model based on full moments has the opposite implications

multilateral productivity comparisons when some outputs are undesirable a nonparametric approach multilateral productivity comparisons of firms producing multiple outputs some of which are undesirable are obtained by making two modifications to the standard farrell approach to efficiency measurement the restriction that production technology satisfy strong disposability of outputs is relaxed to allow for the fact that undesirable outputs may be freely disposable and the efficiency measures are modified to allow for an asymmetric treatment of desirable and undesirable outputs performance measures that satisfy these requirements are calculated as solutions to programming problems the methodology is applied to a sample of mills producing paper and pollutants

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

econometric estimation of producers risk attitudes general methods are proposed for the identification and econometric estimation of the parameters of the distribution of risk attitudes in a producer population the proposed methods also provide the basis for the development of statistical tests of model specification and of behavioral hypotheses econometric risk attitude estimation is shown to be possible under less restrictive conditions than previously believed a moment based version of the general model is applied to indian data and the econometrically estimated risk attitudes are presented and compared to experimental results for a similar group of producers

malmquist indices of productivity growth during the deregulation of norwegian banking 1980 89 productivity growth during the deregulation of the norwegian banking industry is studied within the framework of data envelopment analysis which explicitly allows for multiple outputs introducing malmquist indices for productivity growth total growth can be decomposed into frontier growth and change in each bank s distance to the frontier both the total growth index and its components can be consistently chained over time we find productivity regress at the average bank prior to the deregulation but rapid growth when deregulation took place deregulation also led to less dispersion of productivity levels within the industry

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

handling uncertainty in agricultural supply chain management a state of the art given the evolution in the agricultural sector and the new challenges it faces managing agricultural supply chains efficiently has become an attractive topic for researchers and practitioners against this background the integration of uncertain aspects has continuously gained importance for managerial decision making since it can lead to an increase in efficiency responsiveness business integration and ultimately in market competitiveness in order to capture appropriately the uncertain conjuncture of most agricultural real life applications an increasing amount of research effort is especially dedicated to treating uncertainty in particular quantitative modeling approaches have found extensive use in agricultural supply chain management this paper provides an overview of the latest advances and developments in the application of operations research methodologies to handling uncertainty occurring in the agricultural supply chain management problems it seeks to i offer a representative overview of the predominant research topics ii highlight the most pertinent and widely used frameworks and iii discuss the emergence of new operations research advances in the agricultural sector the broad spectrum of reviewed contributions is classified and presented with respect to three most relevant discerned features uncertainty modeling types programming approaches and functional application areas ultimately main review findings are pointed out and future research directions which emerge are suggested

generalized optimal hedge ratio estimation a generalized approach to estimating optimal hedge ratios on futures markets is developed the generalized approach is not difficult to apply and provides a framework for evaluating the appropriateness of conventional simple regression approaches to optimal hedge ratio estimation in an application to storage hedging of corn soybeans and wheat it is found that simple regression using price levels or returns leads to errors in optimal hedge ratio estimation but that simple regression using price changes provides reasonably accurate estimates

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

total factor productivity growth technological progress and technical efficiency change dimensions of productivity change in yugoslavia 1965 1978 this article total factor productivity growth technological progress and technical efficiency change dimensions of productivity change in yugoslavia 1965 78 was reprinted with permission from the december 1982 issue of the economic journal this article proposes a methodology that decomposes total factor productivity change into two distinct elements technological progress and changes in technical efficiency technological progress is defined as the change in the best practice production frontier all other productivity change is attributed to technical efficiency change the article provides a theoretical framework for decomposing total factor productivity growth as well as a specification and estimation of the deterministic frontier production function it employs a programming technique to estimate a flexible functional form of the production frontier the paper then applies this technique to empirical data from yugoslavia of the period from 1965 to 1978 it concludes that for yugoslavia improvements to technical efficiency comprise the dominant contribution to total factor productivity change this agrees with accumulating evidence that in many developing economies productivity gain due to technological mastery of imported technology is substantial

cost efficiency measurement with price uncertainty a dea application to bank branch assessments this paper enhances cost efficiency measurement methods to account for different scenarios relating to input price information these consist of situations where prices are known exactly at each decision making unit dmu and situations with incomplete price information the main contribution of this paper consists of the development of a method for the estimation of upper and lower bounds for the cost efficiency ce measure in situations of price uncertainty where only the maximal and minimal bounds of input prices can be estimated for each dmu the bounds of the ce measure are obtained from assessments in the light of the most favourable price scenario optimistic perspective and the least favourable price scenario pessimistic perspective the assessments under price uncertainty are based on extensions to the data envelopment analysis dea model that incorporate weight restrictions of the form of input cone assurance regions the applicability of the models developed is illustrated in the context of the analysis of bank branch performance the results obtained in the case study showed that the dea models can provide robust estimates of cost efficiency even in situations of price uncertainty

technical scale and allocative efficiencies in u s banking an empirical investigation a nonparametric frontier approach is used to calculate the overall technical pure technical allocative and scale efficiencies for a sample of 322 independent banks the sample was drawn from the federal deposit insurance corporation tapes on the reports of condition and reports of income call reports for the year 1986 the results indicated a low level of overall efficiency the main source of inefficiency was technical in nature rather than allocative separate efficiency frontiers were constructed to test the effect of branching however the distributions of efficiency measures for branching and non branching banks were not found to be different

risk aversion and price risk in duality models of production a linear mean variance approach a duality model of production is developed that permits risk aversion and price uncertainty the linear mean variance framework employed is tractable for empirical research in contrast to duality models of risk based on a generalized expected utility function the framework is more general than in standard price certainty models while retaining the simplicity needed for empirical research

risk aversion and yield uncertainty in duality models of production a mean variance approach a duality model of production is developed that endogenizes stochastic output decisions under risk aversion the model incorporates both yield and price uncertainty and nonlinear mean variance risk preferences this permits modeling of the firm s expected output supply and input demand decisions under risk and also in principle the firm s output variance decisions the duality model is tractable for empirical research

a note on efficiency and productivity growth in the korean banking industry 1992 2002 abstract in this paper we present estimates of korean bank inefficiency and productivity change for the period 1992 2002 that are derived from the directional technology distance function our method controls for loan losses that are an undesirable by product arising from the production of loans and allows the aggregation of individual bank inefficiency and productivity growth to the industry level our findings indicate that technical progress during the period was more than enough to offset efficiency declines so that the banking industry experienced productivity growth

the economics and econometrics of damage control concern for the potentially harmful side effects of agricultural chemical inputs especially pesticides highlights the need to accurately determine the economic levels of their use we consider three model specification issues interaction of direct production inputs with damage control inputs in damage abatement justification for a priori exclusion of production inputs from the abatement function and the motivations and consequences of alternative stochastic specifications empirical analysis using farm level data shows that misspecification of the stochastic element in the production function can overestimate the marginal physical productivity of pesticides and grossly underestimate the responsiveness of demand to increases in pesticide prices

technological change and risk management an application to the economics of corn production the paper investigates the linkages between technological change and production risk with an application to corn the effects of technology on risk exposure are analyzed we define technological progress to be risk increasing risk decreasing if it increases decreases the relative risk premium the analysis is applied to panel data from wisconsin research stations conditional moments including mean variance and skewness of corn yield grain moisture and corn profit are estimated for different sites we investigate how the trade off between expected return and the risk premium varies over time and over space the empirical results indicate that technological progress contributes to reducing the exposure to risk as well as downside risk in corn production although this effect varies across sites they also stress the role of the relative maturity of corn hybrids as a means of managing risk

joint estimation of risk preferences and technology flexible utility or futility a thought experiment is designed to investigate whether the structure of risk aversion i e the changes in absolute or relative risk aversion associated with changes in wealth can be estimated with reasonable precision from agricultural production data findings strongly suggest that typical production data are unlikely to allow identification of the structure of risk aversion a flexible utility parameterization is found to slightly worsen technology parameter estimates results also indicate that even under a restricted utility specification utility parameter estimates are biased further their quality is much worse when shocks are not large or samples are small

meteor showers or heat waves heteroskedastic intra daily volatility in the foreign exchange market this paper seeks to explain the causes of volatility clustering in exchange rates careful examination of intra daily exchange rates provides a test of two hypotheses heat waves and meteor showers the heat wave hypothesis is that the volatility has only country specific autocorrelation alternatively the meteor shower is a phenomenon of intra daily volatility spillovers from one market to the next using the garch model to specify the heteroskedasticity across intra daily market segments we find that the empirical evidence is generally against the null hypothesis of the heat wave using a volatility type of vector autoregression we examine the impact of news in one market on the time path of per hour volatility in other markets

the hedging performance of electricity futures on the nordic power exchange the nordic power exchange nord pool the first multinational exchange for electricity trading has existed since january 1996 spot and futures contracts are traded on this exchange and its typical characteristics are very high volatilities as well as non normally distributed returns this article looks at electricity futures and how they can be used for short term hedging of positions taken in the spot market it studies the minimum variance hedge ratio and how it can be estimated in different ways the traditional naive hedge and the ols hedge are compared out of sample to more elaborate moving average and garch hedges and the empirical results indicate some gains from hedging with futures despite the lack of straight forward arbitrage possibilities in the electricity market furthermore we find a slightly better performance of the simple ols hedge compared to the conditional hedges

school attendance child labor and local labor market fluctuations in urban brazil abstract while the income poverty effect on child labor is long established as a main determinant of child labor there is a growing body of literature considering the pull of the labor market this paper demonstrates that after controlling for household characteristics employment rates for 14 16 year old boys and girls in urban brazil increase as local labor market opportunities improve children are also more likely to leave school as local labor market conditions become more favorable the relationship between children s schooling and work and local labor market conditions changes in years of crisis compared to other years the effects of macroeconomic fluctuations on children s school and work behavior are examined with particular focus on whether the income effect or substitution effect dominates as macroeconomic conditions change over time the study uses data from the pesquisa nacional amostra de domicilios a large household survey that is conducted almost annually by the ibge we use variation in the urban areas of 25 states over 12 years to identify the aggregate effects

the effects of deregulation on the performance of financial institutions the case of spanish savings banks this paper examines the impact of regulatory reform on the performance of spanish savings banks the focus is whether increased competition brought on by deregulation affected performance of banks over time output technical efficiency which is defined in terms of the production possibility frontier is also examined empirical results show declining levels of output technical efficiency along with a significantly high rate of technical progress in spite of declining technical efficiency during this period evidence of an increasing trend in productivity growth is found

diversity productivity and temporal stability in the economies of humans and nature abstract recent advances in ecology are of great potential relevance to economists here we present two ecological models of mechanisms of competition and coexistence and use these to derive how the primary productivity of ecosystems the amount of carbon dioxide removed from the atmosphere and stored by plants the efficiency of resource use and the spatial and temporal variability of productivity and resource use should depend on diversity we then discuss the relevance of these results to 1 ecosystem services and the economic value of diversity and 2 the functioning of any competitive system including the economy

measuring environmental efficiency of industry a case study of thermal power generation in india technical and environmental efficiency of some coal fired thermal power plants in india is estimated using a methodology that accounts for firm s efforts to increase the production of good output and reduce pollution with the given resources and technology the methodology used is directional output distance function estimates of firm specific shadow prices of pollutants bad outputs and elasticity of substitution between good and bad outputs are also obtained the technical and environmental inefficiency of a representative firm is estimated as 0 06 implying that the thermal power generating industry in andhra pradesh state of india could increase production of electricity by 6 while decreasing generation of pollution by 6 this result shows that there are incentives or win win opportunities for the firms to voluntarily comply with the environmental regulation it is found that there is a significant variation in marginal cost of pollution abatement or shadow prices of bad outputs across the firms and an increasing marginal cost of pollution abatement with respect to pollution reduction by the firms this result calls for the use of economic instruments like pollution taxes instead of command and control regulation used currently in india to reduce air pollution

measuring technical efficiency in the presence of pesticide spillovers and production uncertainty the case of dutch arable farms pesticides dynamic effects and production uncertainty play an important role in farmers production decisions pesticides have a current production impact through reducing crop damage in the current period and a future impact through impacting the farm biodiversity which alters the future production environment this study presents the difference in inefficiency arising from models that ignore the dynamic effects of pesticides in production decisions and the impact of production uncertainty a dynamic data envelopment analysis dea model is applied to outputs inputs and undesirables of dutch arable farms over the period 2003 2007 a bootstrap approach is used to explain farmers performance providing empirical representations of the impact of stochastic elements on production these empirical representations are used to adjust firms inefficiency scores to incorporate production uncertainty in efficiency evaluation we find that efficiency increased dramatically when a production technology representation that considers both pesticides dynamic impacts and production uncertainty is adopted

weak disposability in nonparametric production analysis with undesirable outputs environmental economics and natural resources group at wageningen university in the netherlands weak disposability of outputs means that firms can abate harmful emissions by decreasing the activity level modeling weak disposability in nonparametric production analysis has caused some confusion this article identifies a dilemma in these approaches conventional formulations implicitly and unintentionally assume all firms apply uniform abatement factors however it is usually cost effective to abate emissions in those firms where the marginal abatement costs are lowest this article presents a simple formulation of weak disposability that allows for non uniform abatement factors and preserves the linear structure of the model

an activity analysis model of the environmental performance of firms application to fossil fuel fired electric utilities the productivity of firms when some outputs pollution are undesirable has been studied in the literature for some time in this paper we introduce an environmental performance indicator based on the decomposition of overall factor productivity into a pollution index and an input output efficiency index this indicator is compared to the more conventional jaggi and freedman 1992 model results are given for illustrative purposes using data from u s fossil fuel fired electric utilities the rankings of the utilities obtained with the two models show significant divergence which is due to the different ways in which the undesirable outputs are dealt with as well as due to the different possible tradeoffs between the pollutants released into the atmosphere and the resources used as inputs

pesticide use environmental spillovers and efficiency a dea risk adjusted efficiency approach applied to dutch arable farming pesticides are widely used by crop producers in developed countries to combat risk associated with pests and diseases however their indiscriminate use can lead to various environmental spillovers that may alter the agricultural production environment thus contributing to production risk this study utilises a data envelopment analysis dea approach to measure performance of arable farms incorporating pesticides environmental spillovers and output variance as undesirable outputs in the efficiency analysis and taking explicitly into account the effect of pesticides and other inputs on production risk the application focuses on panel data from dutch arable farms over the period 2003 2007 a moment approach is used to compute output variance providing empirical representations of the risk increasing or decreasing nature of the used inputs finally shadow values of risk adjusted inputs are computed we find that pesticides are overused in dutch arable farming and there is a considerable evidence of the need for decreasing pesticides environmental spillovers

optimal hedging in the us natural gas market the effect of maturity and cointegration abstract we use the us natural gas market as the rich experimental context to test multiple features of hedging performances first we compare the hedging effectiveness of a single futures contract i e henry hub used for hedging six different physical price positions second we examine the performance of hedging when one uses a futures contract with time to maturity beyond the hedging horizon i e a non matching hedging strategy finally we quantify the effect of accounting for cointegration and also the time varying volatility in the calculation of optimal hedge ratios as a robustness check we conduct our analysis using both ex ante out of sample and ex post in sample methods our findings suggest that using longer maturity contracts may improve the hedging effectiveness we also find that accounting for cointegration and time varying prices has minimal effect on the hedge ratio and hedging effectiveness for almost all physical prices our findings can inform businesses exposed to commodity price risks in on making better risk management decisions