food versus fuel an updated and expanded evidence abstract this paper replicates the study of zhang et al 2010 food versus fuel what do prices tell us energy policy 38 pp 445 451 we confirm the findings of the original paper that there was only a weak relationship between ethanol and food commodities in the period between march 1989 and july 2008 in addition we extend that study and examine the cointegration relationship between biofuels and related commodities for a considerably enlarged dataset 3 vs 1 market 26 vs 8 commodities analysis up till 2017 vs 2008 weekly vs monthly data frequency focusing on the biofuel markets of brazil the eu and the usa in the three separate periods before during and after the food crisis of 2007 and 2008 we show that studying the time variation of the relationships plays an essential role in their proper understanding our results help to clarify the wide extensive discussion about the role of biofuels prices in food shortages manifested particularly during the food crises in agreement with the original study we confirm that price series data do not support strong statements about biofuels uniformly serving as main leading source of high food prices and consequently the food shortages

bayesian estimation and selection of nonlinear vector error correction models the case of the sugar ethanol oil nexus in brazil nonlinear adjustment toward long run price equilibrium relationships in the sugar ethanol oil nexus in brazil is examined we develop generalized bivariate error correction models that allow for cointegration between sugar ethanol and oil prices where dynamic adjustments are potentially nonlinear functions of the disequilibrium errors a range of models are estimated using bayesian monte carlo markov chain algorithms and compared using bayesian model selection methods the results suggest that the long run drivers of brazilian sugar prices are oil prices and that there are nonlinearities in the adjustment processes of sugar and ethanol prices to oil price but linear adjustment between ethanol and sugar prices

assessing regional environmental efficiency in china with distinguishing weak and strong disposability of undesirable outputs abstract china has developed a remarkable economic growth in the past 30 years by accompanying with undesirable outputs the assumptions of weak and strong of undesirable outputs have become the focus discussion in data envelopment analysis dea models to have a comprehensive environmental efficiency measurement this paper proposes three dea models considering weak disposability strong disposability and distinguishing weak and strong disposability of undesirable outputs respectively we further combine with the malmquist luenberger productivity index to assess the environmental efficiency and the dynamic change trend of 30 provinces in china from 2005 to 2014 the results show that distinguishing technical features of undesirable outputs makes a significant difference to final environmental efficiency score at different regions the environmental efficiency of the whole nation however does not show any increasing trend during the ten years enhancing environmental efficiency of central and west area is an urgent task for chinese government the change trend of malmquist luenberger productivity index and technological change shows a similar shape technical progress is the main driving force to enhance the environmental efficiency relevant suggestions are presented for improving the regional environmental efficiency in china in the future

directional shadow price estimation of co2 so2 and nox in the united states coal power industry 1990 2010 abstract shadow prices also termed marginal abatement costs provide valuable guidelines to support environmental regulatory policies for co 2 so 2 and no x the key contributors to climate change this paper complements the existing models and describes a directional marginal productivity dmp approach to estimate directional shadow prices dsps which present substitutability among three emissions and are jointly estimated we apply the method to a case study of co 2 so 2 and no x produced by coal power plants operating between 1990 and 2010 in the united states we find that dsp shows 1 1 times the maximal shadow prices estimated in the current literature we conclude that estimating the shadow prices of each by product separately may lead to an overestimation of the marginal productivity and an underestimation of the shadow prices

nonparametric production technologies with weakly disposable inputs abstract in models of production theory and efficiency analysis the inputs and outputs are assumed to satisfy some form of disposability in this paper we consider the assumption of weak input disposability it states that any activity remains feasible if its inputs are simultaneously scaled up in the same proportion as suggested in the literature the shephard technology incorporating weak input disposability could be used to evaluate the effect of input congestion we show that the shephard technology is not convex and therefore introduces bias in evaluation of congestion to address this we develop an alternative convex technology whose use in the evaluation of congestion removes the noted bias we undertake a further axiomatic investigation and obtain a range of production technologies all of which exhibit weak input disposability but are based on different progressively relaxed convexity assumptions apart from the evaluation of input congestion such technologies should also be useful in applications in which some inputs are closely related or are overlapping and therefore satisfy only the weak input disposability assumption incorporated in the new models

mixed strategy nash equilibrium in data envelopment analysis abstract in a typical productivity analysis the efficiency measure assumes a perfectly competitive market with an endogenous price and depends on a fixed orientation with respect to a specific firm such as an input oriented measure when an imperfectly competitive market affects the endogenous price however firms may take a mixed strategy approach to address uncertain competition this study proposes a mixed strategy measure msm we construct a model embedded with a data envelopment analysis dea framework that identifies the mixed strategy nash equilibrium in the first stage and considers a probabilistic and multi oriented efficiency measure in the second stage based on the environmental regulation and a typical nash measure we create two indices environmental consistency and strategic consistency to support the business roadmap development we validate the proposed msm with an empirical study of china s electric power industry the results find that the proposed msm complements the nash measure and the msm model successfully supports our two managerial strategies invest in capacity expansion or develop emission abatement technology

nonparametric productivity analysis with undesirable outputs reply hailu and veeman 2001 henceforth hv use both primal nonparametric dea and dual nonparametric frontiers that include undesirable outputs the dual frontier provides the tightest nonparametric outer bound to the unknown underlying technology while the dea frontier provides the tightest innerbound to the technology varian banker and maindiratta chavas and cox all previous nonparametric analyses incorporating undesirable outputs had been based on the dea model and hv highlighted the limitations of this one sided approach by confronting the results from the dea model with those from the dual model the dea model was found to be very poor in terms of discriminating between observations as indicated in hv this is a problem that has also been noted by several other researchers in the conventional productivity literature before i provide specific responses to some of the comments by fare and grosskopf fg i would like to make the following general remarks first hv use input based measures and a variable returns to scale formulation of the dea model however fg support their arguments using output possibility frontiers output based measures and constant returnsto scaleassumptionsthatwerenotusedinhv it is well known that a dea model with constant returns to scale has different characteristics and provides different results compared to those with variable returns second and more importantly it should be noted that the dea model with constant returns to scale does not qualify as the inner nonparametric bound that is the subject of hv s article third the major difference between the weakly disposable and hv dea frontiers becomes irrelevant for measures of efficiency that explicitly penalize extrabadoutput infg sfigure1 forexample the area east of line bc is irrelevant in the hv

shadow pricing of undesirable outputs in nonparametric analysis abstract for three decades a growing interest in the modeling of desirable and undesirable outputs has led to a theoretical and methodological debate in the nonparametric literature on production technology and efficiency the first main discussion is about the way of modeling bad undesirables as inputs or outputs or by transformation functions the second debate concerns the implications of the weak disposability assumption in the modeling of bad outputs in particular the possibility of assigning unexpected signs to shadow prices of bad outputs in addition we point out a current error in the modeling of weak disposability under a variable returns to scale technology in this paper we introduce a hybrid model to ensure the economically meaningful jointness of good and bad outputs while constraining shadow prices of bad outputs to their expected sign we argue that it is a sound compromise to model undesirable outputs with a meaningful primal dual economic interpretation finally we propose an extension to define shadow prices for undesirable outputs following the law of one price loop rule

oil prices and the rise and fall of the us real exchange rate abstract questions of the relative importance of real vs monetary shocks in explaining exchange rate movements still have no widely accepted answer despite their importance both for the research agenda and for policy questions we examine this issue using a variety of empirical techniques for the us effective exchange rate we find that a stable link exists between oil price shocks and the us real effective exchange rate over the post bretton woods period the results suggest that oil prices may have been the dominant source of persistent real exchange rate shocks and that energy prices may have important implications for future work on exchange rate behavior

food energy nexus in europe price volatility approach abstract the literature on food biofuel price volatility spillovers is growing published articles so far have widely ignored nonlinearities and the influence of exogenous variables on volatility patterns this article allows for these issues when characterizing eu biodiesel industry price dynamics while brazilian and us ethanol markets have been thoroughly investigated less attention has been paid to eu biodiesel markets pure eu biodiesel and rapeseed oil prices are the object of our research two different methods are applied to model these data a parametric approach and long et al s 2011 semiparametric approach empirical results suggest significant asymmetries in volatility spillovers between pure biodiesel and rapeseed oil prices rapeseed stock levels and euro dollar exchange rates are found to play a significant role in reducing food and biofuel price volatilities

cointegration and threshold adjustment this article proposes an extension to the engle granger testing strategy by permitting asymmetry in the adjustment toward equilibrium in two different ways we demonstrate that our test has good power and size properties over the engle granger test when there are asymmetric departures from equilibrium we consider an application namely whether there exists cointegration among interest rates for instruments with different maturities this issue has been widely tested with mixed results we argue that either cautious policy or possibly opportunistic behavior on the part of the federal reserve implies that an equilibrium relationship between short and long term interest rates exists but that adjustments from disequilibrium are asymmetric in nature empirical tests using u s yields confirm the asymmetric nature of error correction among interest rates of different maturities

meta data envelopment analysis finding a direction towards marginal profit maximization abstract this paper discusses a new meta dea approach to solve the problem of choosing direction vectors when estimating the directional distance function the proposed model emphasizes finding the direction for productivity improvement rather than estimating the score of efficiency focusing on planning over evaluation in fact the direction towards marginal profit maximization implies a step by step improvement and wait and see decision process which is more consistent with the practical decision making process an empirical study of u s coal fired power plants operating in 2011 validates the proposed model the results show that the efficiency measure using the proposed direction is consistent with all other indices with the exception of the direction towards the profit maximized benchmark we conclude that the marginal profit maximization is a useful guide for determining direction in the directional distance function

alternative measures of environmental technology structure in dea an application abstract the nonparametric data envelopment analysis dea literature on environmental efficiency ee considers handling undesirable outputs in two alternative ways either in their original forms with the assumption that these are weakly disposable or in various translated forms with the assumption that these are strongly disposable choosing a particular approach implies adoption of a particular distinct treatment of undesirable outputs and hence yields a distinct set of ee estimates to explore the effects of the interplay between choice of ee measure and specific treatment of undesirable outputs this paper attempts to generate all possible output oriented ee measures based on these two alternative approaches furthermore guided by the argument that slacks are important in identifying properly the efficiency behavior of firms it proposes two new alternative slacks based formulations of ee one based on the range directional model and the other on the generalized proportional distance function model using a confected data set of ten firms and a real life data set of 22 oecd countries our empirical analysis reveals that first ee scores are influenced not only by the choice of disposability assumption for undesirable outputs but also by the way these are treated in various translated forms second the choice of any particular treatment of undesirable outputs plays no role in influencing the rankings of firms and third our two new alternative ee formulations are at the least viable alternatives to existing ee measures in ranking firms according to their eco efficiency behavior

fdi transfer pricing and the measurement of r d intensity abstract an important determinant of a region s attractiveness to foreign investors is its rate of corporation tax besides stimulating real economic activity low corporation tax rates also induce multinational corporations to shift profits into the jurisdiction frequently through the manipulation of transfer prices this practice can lead to a substantial distortion of output figures since national or sectoral r d intensities are usually measured relative to output transfer pricing also therefore distorts these measurements the present paper proposes a simple alternative measure of r d intensity implementation on irish data shows that the two approaches yield substantially different results

non parametric productivity analysis with undesirable outputs an application to the canadian pulp and paper industry this article extends the chavas cox approach to non parametric analysis by incorporating undesirable outputs to provide a more complete representation of the production technology inner and outer non parametric technology bounds are constructed the methods are illustrated with application to time series data for the canadian pulp and paper industry conventional measures that ignore changes in pollutant outputs underestimate true productivity growth further there is a large gap between estimates generated with reference to inner and outer bounds to the technology suggesting that researchers need to be aware of the limitations of results derived from analyses relying only on dea methods copyright 2001 oxford university press

technical efficiency and impact of environmental regulations in farrow to finish swine production in taiwan this article demonstrates how technical efficiency and the impact of environmental regulations of taiwanese farrow to finish swine production can be estimated in the presence of undesirable outputs the issue of measuring technical efficiencies while considering undesirable outputs has been addressed by past studies but the proper method of including undesirable outputs has always been a subject of debate this article develops a data envelopment analysis dea based model that includes undesirable outputs the technologies of desirable output production and undesirable output control are considered simultaneously this allows one to transform undesirable output into desirable output whereby a traditional shephard distance function can be used to measure technical efficiencies an approach to measuring the impacts due to environmental regulations is then derived empirical results show that larger farms are more technically efficient than small sized farms but no clear conclusions can be reached for the measures of regulatory impact among farms with different sizes on average the sample farms incurred an opportunity cost due to environmental regulations equivalent to 9 8 of market value opportunity costs rise with efficiency

nerlovian revenue inefficiency in a bank production context evidence from shinkin banks the paper further advances the contemporary methodological and empirical research on bank efficiency we introduce a bank two stage network revenue decomposition analysis based on the slack based directional inefficiency measurement framework by building upon the approaches of epure and lafuente 2015 fukuyama and weber 2009 2010 fukuyama and matousek 2017 and fare fukuyama grosskopf and zelenyuk 2015 2016 we apply the model on the segment of japanese financial institutions shinkin banks we examine the efficiency performance of shinkin banks during the period from march 2007 to march 2015 this covers the recent years after the turmoil in the us subprime residential mortgage market which started early 2007 the applied innovative framework is particularly suitable for this type of banks since the financing of their business activities is mainly dependent on the different types of deposits that the proposed model takes into consideration

impact of food price volatility on the us restaurant sector although fluctuations in agricultural commodity prices appear to be a source of risk to the us restaurant sector the effect that volatility of food price has on the performance returns of that s

biofuel related price transmission literature a review abstract in this article an extensive review of the rapidly growing biofuel related time series literature is carried out the data used the modeling techniques and the main findings of this literature are discussed providing a review of this flourishing research area is relevant as a guidepost for future research this literature concludes that energy prices drive long run agricultural price levels and that instability in energy markets is transferred to food markets

distinguishing operational performance in power production a new measure of effectiveness by dea measuring the efficiency of power plant systems requires capturing fluctuations in the level of sales to customers as well as accounting for the effects of regulatory caps on emissions this study proposes a novel effectiveness measure considering desirable outputs and undesirable outputs via data envelopment analysis dea the new measure complements typical efficiency measures we test the validity of the proposed measure with an empirical case study of the fifty u s states and the district of columbia we find that the current interregional electricity transmission plan increases 8 56 in effectiveness for the emissions control we suggest a 9 8 reduction in electricity generation towards an effective production frontier we conclude that the proposed effectiveness measure s ability to distinguish sales and regulation effects from typical productive efficiency eliminates the bias often found in currently used measures

price formation in the german biodiesel supply chain a markov switching vector error correction modeling approach changing linkages between agricultural and energy markets have attracted considerable attention in research and policy discussions during recent years as one of the largest biofuel markets worldwide the german biodiesel market is of particular interest it has grown rapidly since the beginning of the new millennium with this growth being driven mainly by political interventions vertical price transmission channels along the biodiesel supply chain are analyzed in this study we examine the relationship between diesel and biodiesel prices and between rapeseed oil soy oil and biodiesel prices between 2002 and 2008 due to pronounced changes in market conditions and the policy framework a regime dependent markov switching vector error correction model is used the regimes are characterized by markedly different price adjustment behaviors before 2005 and from late 2007 onward a regime characterized by the strong orientation of biodiesel prices toward diesel prices dominates between 2005 and 2007 biodiesel and rapeseed oil prices are mutually interdependent frequent switches between the regimes of the price dynamics during this period indicate a high extent of uncertainty and instability in the market

the dependence structure across oil wheat and corn a wavelet based copula approach using implied volatility indexes abstract this paper examines the dependence structure between three commodities implied volatility indexes oil wheat and corn during bear normal and bull markets and at different scales for this purpose we combine wavelet and copula methods to analyse the changes of the tail dependence at different scales or investment horizons the results support evidence of time varying asymmetric tail dependence between the pair of cereals as well as between oil and the two cereals at different time horizons short term horizon medium term horizon and long term horizon suggesting that the dependence structure is sensitive to time horizons these results have important implications for the analysis of portfolio risk management

accounting for externalities and disposability a directional economic environmental distance function abstract the existence of positive and negative externalities ought to be considered in a productivity analysis in order to obtain unbiased measures of efficiency in this research we present an additive style data envelopment analysis model that considers the production of both negative and positive externalities and permits a limited increase in input utilisation where relevant the directional economic environmental distance deed function is a unified approach based on a linear program that evaluates the relative inefficiency of the units under examination with respect to a unique reference technology we discuss the impact of disposability assumptions in depth and demonstrate how different versions of the deed model improve on models presented in the literature to date

a conditional directional distance function approach for measuring regional environmental efficiency evidence from uk regions abstract this paper by using conditional directional distance functions as introduced by simar and vanhems j econometrics 166 2012 342 354 modifies the model by fare and grosskopf eur j operat res 157 2004 242 245 and examines the link between regional environmental efficiency and economic growth the proposed model using conditional directional distance functions incorporates the effect of regional economic growth on regions environmental efficiency levels the results from uk regional data reveal a negative relationship between regions gdp per capita and environmental inefficiency up to a certain gdp per capita level after that level it appears that the relationship becomes positive as an overall result the regional environmental inefficiency gdp per capita relationship appears to have a u shape form

time frequency causality and connectedness between international prices of energy food industry agriculture and metals abstract this study analyzes the lead lag relationship between the price indices of energy fuels and each of food industrial inputs agriculture raw materials metals and beverages in the time frequency domain to this end we first use the wavelet coherency and phase differences next we use the diebold and yilmaz 2012 and barunik and krehlik 2017 spillover indices to analyse the connectedness among the set of the price indices under consideration the period of the study is 1990m1 to 2017m5 the wavelet coherency results reveal that there are important and significant relations between the fuel and food prices the fuel and industrial prices and the fuel and metal prices these results also show that there are phase relationships between those paired prices the volatility spillover results indicate that the agricultural sector is the most affected by shocks from the other markets the return series of the industrial input prices at all frequencies appears to be the main source of volatility transmission to the prices of the other commodities over the whole period this finding underlines the relevance of the industrial inputs to policy makers particularly when they design policies to provide incentives related to industrial production

non parametric frontier approach to modelling the relationships among population gdp energy consumption and co2 emissions abstract in this paper a non parametric approach based in data envelopment analysis dea is proposed as an alternative to the kaya identity a k a impact this frontier method identifies and extends existing best practices population and gdp are considered as input and output respectively both primary energy consumption and greenhouse gas ghg emissions are considered as undesirable outputs several linear programming models are formulated with different aims namely a determine efficiency levels b estimate maximum gdp compatible with given levels of population energy intensity and carbonization intensity and c estimate the minimum level of ghg emissions compatible with given levels of population gdp energy intensity or carbonization index the united states of america case is used as illustration of the proposed approach

volatility spillovers between food and energy markets a semiparametric approach previous literature on volatility links between food and energy prices is scarce and mainly based on parametric approaches this article examines these links by using a semiparametric garch model recently proposed by long et al 2011 which is essentially a nonparametric correction of the parametric conditional covariance function the analysis focuses on price links between crude oil ethanol and sugar prices in brazil results suggest strong volatility links between the prices studied parametric approximations of the conditional covariance matrix may lead to misleading results that can be improved upon by using nonparametric techniques

congestion measurement in nonparametric analysis under the weakly disposable technology abstract congestion is a widely observed economic phenomenon where outputs are reduced due to excessive amount of inputs the previous approaches to identify congestion in nonparametric analysis only consider desirable outputs in the production process undesirable outputs are usually jointly produced with desirable outputs in this paper we propose an approach for measuring congestion in the presence of desirable and undesirable outputs simultaneously the proposed approach can discriminate between the congested dmus and the truly efficient dmus which are all efficient according to the scores calculated by the directional distance function finally an empirical example is used to illustrate the approach

estimating the shadow prices of so2 and nox for u s coal power plants a convex nonparametric least squares approach abstract weak disposability between outputs and pollutants defined as a simultaneous proportional reduction of both outputs and pollutants assumes that pollutants are byproducts of the output generation process and that a firm can freely dispose of both by scaling down production levels leaving some inputs idle based on the production axioms of monotonicity convexity and weak disposability we formulate a convex nonparametric least squares cnls quadratic optimization problem to estimate a frontier production function assuming either a deterministic disturbance term consisting only of inefficiency or a composite disturbance term composed of both inefficiency and noise the suggested methodology extends the stochastic semi nonparametric envelopment of data stoned described in kuosmanen and kortelainen 2011 applying the method to estimate the shadow prices of so 2 and no x generated by u s coal power plants we conclude that the weak disposability stoned method provides more consistent estimates of market prices

nonlinearities in the u s corn ethanol oil gasoline price system we use a smooth transition vector error correction model to assess price relationships within the u s ethanol industry monthly ethanol corn oil and gasoline prices from 1990 to 2008 are used in the analysis results indicate the existence of long run relationships among the prices analyzed strong links between energy and food prices are identified

price relationships in the petroleum market an analysis of crude oil and refined product prices in this paper the relationships between crude oil and refined product prices are investigated in a multivariate framework this allows us to test several partly competing assumptions of earlier studies in particular we find that the crude oil price is weakly exogenous and that the spread is constant in some but not all relationships moreover the multivariate analysis shows that the link between crude oil prices and several refined product prices implies market integration for these refined products this is an example of supply driven market integration and producers will change the output mix in response to price changes

a critique of non parametric efficiency analysis in energy economics studies abstract the paper reexamines non additive environmental efficiency models with weakly disposable undesirable outputs appeared in the literature of energy economics these efficiency models are used in numerous studies published in this journal and other energy related outlets recent studies however have found key limitations of the weak disposability assumption in its application to environmental efficiency analysis it is found that efficiency scores obtained from non additive efficiency models can be non monotonic in pollution quantities under the weak disposability assumption which is against common intuition and the principle of environmental economics in this paper i present taxonomy of efficiency models found in the energy economics literature and illustrate the above limitations and discuss implications of monotonicity from a practical viewpoint finally i review the formulations for a variable returns to scale technology with weakly disposable undesirable outputs which has been misused in a number of papers in the energy economics literature an application to evaluating the energy efficiencies of 23 european union states is presented to illustrate the problem

multi output efficiency with good and bad outputs abstract cherchye de rock dierynck roodhooft and sabbe 2013 introduced a dea methodology that is specially tailored for multi output efficiency measurement the methodology accounts for jointly used inputs and incorporates information on how inputs are allocated to outputs in this paper we present extensions that render the methodology useful to deal with undesirable or bad outputs in addition to desirable or good outputs interestingly these extensions deal in a natural way with several limitations of existing dea approaches to treat undesirable outputs we also demonstrate the practical usefulness of our methodological extensions through an application to us electric utilities

banks efficiency and credit risk analysis using by production approach the case of iranian banks abstractthis article uses a by production approach that integrates credit risk to monitor bank efficiency the method overcomes the possible misspecification issues of the commonly assumed weak disposability wda of undesirable outputs in addition our measure extends the classic by production approach by including statistical aspects through subsampling techniques we have also provided an algorithm to correct related infeasibilities using this approach we investigate the performance of iranian banks and credit risk management in the sector for the period 1998 2012 non performing loans npls have been used as an undesirable output and proxy for credit risk in our models based on our empirical results although the banks generally exhibited efficiency improvements over time their credit risk performance deteriorated considerably after the regulatory changes introduced in 2005 these findings confirm that credit quality can be monitored more actively across iranian banks

speculation and volatility spillover in the crude oil and agricultural commodity markets a bayesian analysis this paper assesses factors that potentially influence the volatility of crude oil prices and the possible linkage between this volatility and agricultural commodity markets stochastic volatility models are applied to weekly crude oil corn and wheat futures prices from november 1998 to january 2009 model parameters are estimated using bayesian markov chain monte carlo methods speculation scalping and petroleum inventories are found to be important in explaining the volatility of crude oil prices several properties of crude oil price dynamics are established including mean reversion an asymmetry between returns and volatility volatility clustering and infrequent compound jumps we find evidence of volatility spillover among crude oil corn and wheat markets after the fall of 2006 this can be largely explained by tightened interdependence between crude oil and these commodity markets induced by ethanol production

price transmission and asymmetric adjustment in the spanish dairy sector asymmetric threshold vector error correction models are applied to monthly price data to analyse price relationships and patterns of transmission among farm and retail markets for a variety of dairy products in spain the results suggest that asymmetries affect a conspicuous part of the raw milk processed in spain implications for the organizational structure of spanish dairy markets are offered

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

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

the impacts of biofuel targets on land use change and food supply a global cge assessment this study analyzes the long term impacts of large scale expansion of biofuels on land use change food supply and prices and the overall economy in various countries or regions using a global computable general equilibrium model augmented by a land use module and detailed representation of biofuel sectors the study finds that an expansion of global biofuel production to meet currently articulated or even higher national targets in various countries for biofuel use would reduce gross domestic product at the global level however the gross domestic product impacts are mixed across countries or regions the expansion of biofuels would cause significant land re allocation with notable decreases in forest and pasture lands in a few countries the results also suggest that the expansion of biofuels would cause a reduction in food supply although the magnitude of the impact on food supply at the global level is not as large as perceived earlier it would be significant in developing countries like india and those in sub saharan africa agricultural commodities such as sugar corn and oil seeds which serve as the main biofuel feedstocks would experience significant increases in their prices in 2020 compared with the prices at baseline due to the expansion of biofuels to meet the existing targets

non parametric and parametric modeling of biodiesel sunflower oil and crude oil price relationships abstract multivariate local linear regression and parametric error correction models are applied to assess price linkages and price transmission patterns between food and energy prices in spain weekly biodiesel sunflower and crude oil prices observed from november 2006 to october 2010 are used in the empirical analysis results suggest the existence of a long run equilibrium relationship between the three prices studied biodiesel is the only variable that adjusts to deviations from this long run relationship local linear regression techniques show that the speed of adjustment of biodiesel prices is faster when biodiesel is relatively cheap than when it is expensive energy prices are also found to influence sunflower oil prices through short run price dynamics

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

a multiplicative environmental dea approach to measure efficiency changes in the world s major polluters we propose a multiplicative environmental data envelopment analysis me dea approach to measure the performance of 46 countries that generate most of the world s carbon dioxide co2 emissions in the model we combine economic labour and capital environmental freshwater and energy inputs with a desirable output gdp and three undesirable outputs co2 methane and nitrous oxide emissions we rank each country according to the optimum use of its resources employing a multiplicative extension of environmental dea models by computing partial efficiency scores for each input and output separately we thus identify major sources of inefficiency for all sample countries based on the partial efficiency scores obtained from the model we define aggregate economic energy and environmental efficiency indexes for 2002 2007 and 2011 reflecting points in time before and after the official enactment of the kyoto protocol we find that for most countries efficiency scores increase over this period in addition there exists a positive relationship between economic and environmental efficiency although at the same time our results suggest that environmental efficiency cannot be realized without first reaching a certain threshold of economic efficiency we also find support for the paradox of plenty whereby an abundance of natural and energy resources results in their inefficient use

measuring environmentally sensitive productivity growth an application to the urban water sector the energy use and greenhouse gas emissions in the provision of urban water and sewerage services have become an increasingly important issue in recent times however the impact of negative externalities such as greenhouse gas emissions on the productivity of urban water provision has received less attention in the literature this paper applies the global malmquist luenberger gml productivity index which accounts for undesirable outputs in order to evaluate the productivity trends in the australian urban water sector results indicate that the inclusion of greenhouse gas emissions significantly influences the productivity measurement findings also indicate that the conventional index which disregards undesirable outputs over states the productivity growth despite a declining trend in greenhouse emissions over the period the overall productivity trend of the urban water sector experienced a downward trend while accounting for bad output this productivity decline occurs in a period of prolonged drought water security concerns and increased reliance on desalinization and water recycling

fossil fuel price uncertainty and feedstock edible oil prices evidence from mgarch m and virf analysis abstract this paper focuses on examining the impact of crude oil price volatility on the price changes of major edible oils rapeseed soybean and sunflower which are the main feedstock for the biodiesel industry in the european union for this purpose a four variate version of non diagonal garch in mean model that allows for asymmetry in the variance covariance matrix is used an important conclusion that emerges from this study is that the crude oil price uncertainty appears to be responsible for a significant decline in price returns of major feedstock edible oils considered in this study the volatility impulse response analyses support the conclusion that the conditional variances of both edible and crude oil and covariances between them are generally highly responsive to historical shock however the size of the impacts is mainly commodity specific finally we investigate the causality from crude oil price volatility to edible oil prices and the effects of oil price shocks on edible oil prices by using the granger causality test and generalized impulse response function analysis respectively the empirical results show that there is strong evidence of causality from crude oil price volatility to all edible oil prices under study and generalized impulse response analysis shows that the edible oil markets significantly respond to the shocks in oil prices

economic value of greenhouse gases and nitrogen surpluses society vs farmers valuation abstract livestock supply must challenge the growth of final demand in the developing countries this challenge has to take into account its ecological effects since the dairy and livestock sectors are clearly pointed out as human activities which contribute significantly to environmental deterioration therefore livestock activity models have to include desirable and undesirable outputs simultaneously using this perspective we implement a data envelopment analysis model to evaluate shadow prices of outputs under contradictory objectives between the society and the farmers we show that farmers are able to reduce pollution significantly if society accepts to balance farmers opportunity cost finally we observe that initial levels of the co 2 tax implemented in european countries are in line with farmers valuation while the current level of the co 2 tax tends to reach the value of pollution targeted by the society

modeling asymmetric comovements of asset returns existing time varying covariance models usually impose strong restrictions on how past shocks affect the forecasted covariance matrix in this article we compare the restrictions imposed by the four most popular multivariate garch models and introduce a set of robust conditional moment tests to detect misspecification we demonstrate that the choice of a multivariate volatility model can lead to substantially different conclusions in any application that involves forecasting dynamic covariance matrices like estimating the optimal hedge ratio or deriving the risk minimizing portfolio we therefore introduce a general model which nests these four models and their natural asymmetric extensions the new model is applied to study the dynamic relation between large and small firm returns article published by oxford university press on behalf of the society for financial studies in its journal the review of financial studies