from shadow to green linking environmental fiscal reforms and the informal economy in the past few decades many papers have analysed in some depth different environmental tax reforms and the double dividend hypothesis i e the possibility of improving not only the environment but also the economy through the reduction of distortions in the tax system recently more stress has been placed on testing empirically what effects a reduction in labour taxes may have on unemployment when accompanied by a carbon or other environmental tax however such studies have not modelled the effects of the presence of a shadow economy even though informal markets account for a significant and growing part of gdp in many developed economies this paper analyses this link using an applied general equilibrium model for the case of spain which has one of the highest unemployment rates in the world and one of the biggest informal economies of any wealthy country we conclude that our analysis strengthens the case for an environmental tax reform in spain if revenues from a co2 tax are recycled via a labour tax reduction

a real options approach to the valuation of a forestry investment abstract the theory of real options is used to model the optimal tree harvesting decision the value of the option to harvest is estimated using a dynamic programming approach and a general numerical solution technique suitable for any type of stochastic process for prices the conditions under which the optimal harvest time is independent of price are examined in addition the impact of assuming future lumber prices are mean reverting is considered it is found that option value and optimal cutting time are significantly different under the mean reversion assumption compared to geometric brownian motion

the tree cutting problem in a stochastic environment the case of age dependent growth abstract harvest policies are derived for growing biological assets e g forests livestock subject to stochastic age dependent growth and price uncertainty the task posed is analyzed as a continuous time optimal stopping problem for diffusion processes both single and ongoing rotation problems are considered qualitative comparative static and numerical results are provided

pre announcement and timing the effects of a government expenditure shock abstract an econometric strategy to identify a pre announced fiscal policy shock is proposed i show that the reduced form innovations can be recovered by estimating a vector moving average model using the kalman filter the structural effects are identified exploiting the shock s pre announced nature which leads to potentially different signs of the responses of some endogenous variables during the announcement and after the realization of the shock i illustrate my strategy by identifying a pre announced shock to government consumption expenditures i find that the response of private consumption is significantly negative on impact rises and becomes significantly positive two quarters after the realization of the policy shock

carbon subsidies taxes and optimal forest management we consider the effect of carbon credit payment schemes on forest owners land use and harvest decisions we study two possible credit allocation regimes one where credits are allocated according to the actual amount of carbon sequestered by the trees on a piece of land and another where credits are allocated according to the long run potential to sequester carbon on the land using a real options model with uncertain future timber prices we examine the effect on the timing of harvests and the replanting abandonment decision we show that both schemes discourage deforestation compensating growers for actual carbon sequestration leads to longer rotation periods between harvests while basing compensation only on the long run potential level of sequestration induces shorter rotation periods the former scheme leads to greater benefits of carbon sequestration at lower cost than the latter scheme although inducing moderate levels of sequestration is expensive under both schemes the cost falls dramatically when the level of payments climbs above some threshold indeed providing the payments are sufficiently generous carbon credit payment schemes offer an effective means of increasing carbon sequestration

environmental policy public finance and the labour market in a second best world abstract environmental and tax policies and the optimal provision of clean and dirty public goods are analysed within the context of a second best framework of optimal taxation households consume both clean and dirty commodities degradation of the natural environment occurs due to the consumption of dirty private and public goods but can be offset when the government engages in abatement activities increased environmental concern implies a higher dirt tax a lower tax on labour less employment more public abatement and a cleaner environment if the elasticity of substitution between private consumption commodities and leisure is large and that between clean and dirty goods is small public consumption may expand while private consumption contracts otherwise public consumption falls

forest valuation under the new zealand emissions trading scheme a real options binomial tree with stochastic carbon and timber prices under the new zealand emissions trading scheme forests planted on or after january 1 1990 earn carbon credits these credits have to be repaid when the forest is harvested this paper analyses the effects of this scheme on the value of bareland on which radiata pine is to be planted a real options method is developed and applied assuming stochastic carbon and timber prices we find that land value increases by about 73 with the optimal rotation age substantially lengthened the derived optimal harvest price thresholds are useful in deciding whether to harvest or to wait jel q23 q28

should high tax countries pursue revenue neutral ecological tax reforms abstract a politically intriguing question concerning the effects of a revenue neutral ecological tax reform is whether such a political measure may succeed in providing a double dividend to improve environmental quality and increase employment simultaneously theoretical studies reveal that for a competitive labor market a green tax reform hardly yields a positive employment effect whereas for a non competitive market such an effect may well be obtained however little attention has focused on whether the ecological dividend remains attainable when an employment dividend accrues we show for three different non competitive labor market scenarios that a positive employment effect can be expected but that for high tax countries environmental quality plausibly deteriorates when a revenue neutral ecological tax reform is implemented

the value of adaption climate change and timberland management abstract adaptation to exogenous change occurs on both intensive and extensive margins whether and how one accounts for human adaptation directly affects estimates of the economic consequences of environmental change estimates that are both critical in informing policy decisions and notoriously difficult to value this paper introduces and applies an analytical framework for placing an economic value on adaptation we explore the issue first in a stylized model that facilitates making concrete generalizations about the kinds of adaptations that generate high or low economic value we then test the soundness of our insights by incorporating learning and adaptive decision making into a structural dynamic forestry model where climate change is imposed exogenously and agents respond optimally using downscaled climate projections integrated with site and species specific timber productivity data we estimate the economic value of adaptation to climate change within the california timber industry we find on the intensive margin changing the rotation intervals will yield a low value of adaptation but on the extensive margin replanting more suitable tree species can yield significant value

measuring the impact of fiscal policy in the face of anticipation a structural var approach empirical estimates of the impact of government spending shocks disagree on central issues such as the size of output multipliers and the responses of consumption and the real wage one explanation for the disagreement is that fiscal shocks are often anticipated due to misspecification of the information set anticipation effects may invalidate svar estimates of impulse responses we use economic theory to derive a fiscal svar estimator that is applicable when fiscal shocks are anticipated we study its properties and apply it to us data we fail to find evidence that anticipation effects overturn the existing findings from the fiscal svar literature despite years of intensive research the empirical literature on fiscal policy has yet to reach consensus on the macroeconomic impact of fiscal policy shocks disagreements concern central issues such as the size of output multipliers and the impact of government spending shocks on consumption and the real wage clearly such level of disagreement constrains our ability to give simple guidelines for the operation of one of the most important stabilisation policies a key empirical obstacle is the measurement of innovations to fiscal policy one strand of the literature employs structural vector autoregressive svar methods and achieves identification based on the presence of decision lags or sign restrictions

optimal adaptive price search consider the problem of a consumer desiring to buy a good which is sold at a variety of prices such a buyer will be able to obtain a sequence of price quotations from various sellers when should the buyer stop searching for a lower price if he continues he may obtain a lower price but he incurs additional time effort and expense in searching the optimal price search decision is one of balancing the expectation of a possibly lower price obtained by continued search against cumulative costs from search when the prices arise from a known probability distribution the optimal search strategy has certain well defined and desirable properties in the more realistic case that the buyer has only partial information about the price distribution and must update his beliefs after observing prices in the marketplace the problem becomes more complex and search strategies become less well behaved the major purpose of this article is to determine new conditions under which optimal policies have these desirable characteristics in the case where the consumer possesses only incomplete information about the distribution of prices price quotations he receives in addition to providing him with price possibilities provide him with information about that distribution rothschild 151 in citing an unpublished paper of gastwirth has noted that small specification errors for an assumed distribution can lead to substantial changes in expected number of searches and expected cost consequently the assumption of a known distribution of prices can have a profound effect on total cost 1 0022 053 l 8 l 040001 20 02 00 o

the reaction of household consumption to predictable changes in social security taxes the key implication of rational expectations and the basic life cycle permanent income hypothesis that predictable changes in income have no effect on the growth rate of consumption expenditures is examined this implication is important for understanding the effectiveness and optimal timing of fiscal policy the causes and propagation of business cycles and the effects of income fluctuations on the growth rate of the economy using household level consumption data from the consumer expenditure survey whether expenditures on nondurable goods increase contemporaneously with predictable changes in social security tax withholding is tested it is found that households do change their consumption expenditures in response to the predictable fluctuations in income induced by the social security tax system

the decision to conserve or harvest old growth forest abstract the decision to harvest or conserve old growth forest is formulated as a stochastic decision problem in continuous time uncertainty in future amenity values for standing forest and in future timber revenues for harvested forest are included in the model along with the risk of catastrophic destruction by fire pest infestation etc it is shown how the decision problem can be expressed as an optimal stopping problem which can be solved analytically the optimal decision rule is shown to depend on how the ratio of current timber value to the current expected present value of amenity benefits foregone through harvesting compares with some critical level the effects of changes in uncertainty and other parameters on the optimal rule are discussed also it is shown how the cost benefit analysis and certainty equivalence procedures lead to premature harvesting and the expected loss in survival time for these sub optimal procedures is calculated

environmental policy tax incidence and the cost of public funds this paper studies under what conditions a double dividend may occur in the sense that both environmental quality and employment rise a simple static general equilibrium model is employed in which tax policy faces the dual task of internalising a negative environmental externality and raising revenue to finance public consumption the model features a clearing labour market with both labour demand and supply and a fixed factor of production e g capital hence we can study tax incidence and its effect on employment environmental quality and the marginal cost of public funds it is shown for the case of an upward sloping labour supply curve and less than full tax shifting by employers that a shift towards greener preferences cannot yield a double dividend even if the fixed factor is important however if labour supply curve bends backwards more environmental concern confers a double dividend

options uncertainty and sunk costs an empirical analysis of land use change abstract in a real option model of land conversion incorporating return uncertainty and sunk costs optimal conversion thresholds are significantly higher than those from expected net present value models not accounting for these factors empirical tests of conversion from agriculture to forest suggest that landowners value the option to convert when making conversion decisions higher uncertainty in returns to all potential uses and lower correlation between shocks to agricultural and forest returns decreases the likelihood of conversion estimates indicate a significant impact on conversion decisions with approximations of option values ranging from 7 to 81 of the expected value of the land asset

estimating the influence of u s ethanol policy on plant investment decisions a real options analysis with two stochastic variables abstract u s ethanol policies have contributed to changes in the levels and the volatilities of revenues and costs facing ethanol firms the implications of these policies for optimal investment behavior are investigated through an extension of the real options framework that allows for the consideration of volatility in both revenue and cost components as well as the correlation between them the effects of policy affecting plant revenues dominate the effects of those policies affecting production costs in the absence of these policies much of the recent expansionary periods would have not existed and market conditions in the late 1990s would have led to some plant closures we also show that regardless of plant size u s ethanol policy has narrowed the distance between the optimal entry and exit curves implying a more narrow range of inactivity and indicative of a more volatile evolution for the industry than would have existed otherwise

the optimal production of an exhaustible resource when price is exogenous and stochastic this paper examines the optimal production of a resource such as oil when its price is determined exogenously e g by a cartel such as opec and is subject to stochastic fluctuations away from an expected growth path we first examine the dependence of production on extraction cost and show that the conventional exponential decline curve is indeed optimal if marginal cost is constant with respect to the rate of extraction but is a hyperbolic function of the reserve level we next show that uncertainty about future price affects the optimal production rate in two ways first if marginal cost is a convex concave function of the rate of production stochastic fluctuations in price raise lower average cost over time so that there is an incentive to speed up slow down production second the option value of the reserve i e the ability to withhold production indefinitely and never incur the cost of extraction provides an incentive to slow down the rate of production

asset retirement with infinitely repeated alternative replacements harvest age and species choice in forestry abstract at what age should productive assets be retired how should replacements be chosen when they differ in their uncertain ability to generate future incomes as a particular version of that problem we study the tree harvesting decision with two possible replacement species whose values as timber are stochastic and whose growth functions are deterministic in the single rotation wicksell problem starting with a bare piece of land an empty shop it is optimal to choose and plant one species immediately if its current value is sufficiently high relative to that of the other species the alternative equipment however if the species are insufficiently price differentiated it is preferable to leave the land vacant the shop empty despite the opportunity cost of doing so in the repeated version of the problem it is never optimal to leave the land bare provided the cost of replacement is null furthermore the optimal harvest tree retirement age not only depends on the price and current productivity of the trees in place but also on the price and productivity of the other species because it may replace the current one the harvest age reaches a peak at some critical threshold of the relative price that signals the necessity to switch to the alternative species indeed this is when the opportunity cost of choosing one alternative replacement over the other is the highest the land value and also the value of the firm is similar to an american option with free boundary infinite expiry period and endogenous payoff the paper highlights the opportunity cost of alternative replacement options and the central role of their volatility in both asset retirement and replacement choice decisions all results are derived analytically a numerical treatment by the penalty method completes the resolution

wicksellian theory of forest rotation under interest rate variability abstract we apply the wicksellian single rotation framework to cover the unexplored case of variable and stochastic interest rate we provide a mathematical characterization of the two dimensional optimal stopping problem and show in the presence of amenity valuation that increased interest rate volatility lengthens the optimal rotation period and increases the value of the optimal policy by modelling the interest rate as a mean reverting process and forest value as a geometric brownian motion and abstracting from amenity valuation we present an explicit solution for the problem numerical illustrations indicate that interest rate volatility has a significant and non linear impact on optimal rotation

a stochastic analysis of the tree paradigm abstract the tree paradigm which is a problem in optimal stopping has important ramifications for human capital acquisition search behavior firm entry and in the theory of renewable resources our paper extends previous work in the stochastic literature on several fronts we exhibit a tractable solution to the rotation problem for the stochastic model analyze the effects of inputs which control the growth process and illustrate our results with a multi stage learning problem

taxation and rotation age under stochastic forest stand value abstract the paper uses both the single rotation and ongoing rotation framework to study the impact of yield tax lump sum tax and tax on interest rate earnings on the privately optimal rotation period when forest stand value is stochastic and forest owners are risk averse or risk neutral under risk aversion the optimal harvesting threshold is lower and therefore the expected rotation period shorter than under risk neutrality both in the single and ongoing rotation cases whether the forest owner is risk averse or risk neutral a higher yield tax a higher lump sum tax or a higher tax on interest rate earnings raise the optimal harvesting threshold numerical results indicate that the optimal harvesting threshold increases less rapidly under risk aversion than under risk neutrality with an increase in either a yield tax or the volatility of forest stand value

non renewability in forest rotations implications for economic and ecosystem sustainability abstract the forest rotations problem has been considered by generations of economists fisher 1930 boulding 1966 samuelson 1976 traditionally the forest resource across all future harvest periods is assumed to grow without memory of past harvest periods this paper integrates economic theory and intertemporal ecological mechanics linking current harvest decisions with future forest growth financial value and ecosystem health results and implications of a non renewable forest resource and the influence of rotation length and number on forest recovery are reported cost estimates of moving from short term economic rotations to long term ecological rotations suggest the level of incentive required for one aspect of ecosystem management a net private cost of maintaining ecosystem health emerges and for public policy purposes can be compared with measures of non timber amenity values and social benefits exhibiting increasing returns to rotation length

good timing the economics of optimal stopping abstract this paper presents an economic interpretation of the optimal stopping of perpetual project opportunities under both certainty and uncertainty prior to stopping the expected rate of return from delay exceeds the rate of interest the expected rate of return from delay is the sum of the expected rate of change in project value and the expected rate of change in the option premium associated with waiting at stopping the expected rate of return from delay has fallen to the rate of interest viewing stopping in this way unifies the theoretical and practical insights of the theory of stopping under certainty and uncertainty

are consumers forward looking evidence from fiscal experiments how changes in current and future income affect consumer spending is a perennial question in macroeconomics and public finance theoretical constructs such as the permanent income hypothesis are of limited assistance in resolving this issue because they neglect borrowing constraints and other market imperfections that can significantly affect the marginal propensity to spend out of current income recent empirical work has also proven inconclusive since whether consumption responds to income fluctuations by more or less than the permanent income hypothesis predicts turns critically upon whether disposable income follows a random walk or is stationary around a longrun trend see john campbell and angus deaton 1987 this controversy is unlikely to be resolved conclusively because it is notoriously difficult to distinguish a stationary but highly persistent time series from one that is nonstationary these difficulties suggest the importance of searching for natural experiments income shocks with predictable and well understood effects on future income to test models of consumer behavior changes in federal tax and transfer policy during the last two decades provide several episodes of this type analyzing the effects of these tax changes is also central to understanding the role of fiscal policy in affecting national saving this paper examines two aspects of consumer response to tax changes section i argues that consumption responds to temporary income tax shocks by more than the permanent income hypothesis would suggest results from the 1975 tax rebate in particular suggest that a 1 increase in transitory income raises spending by about 20 cents section ii examines consumption responses to tax announcements although the results are not conclusive they suggest that some consumers do not adjust consumption in anticipation of tax changes the final section sketches some implications for analyzing fiscal policy

regime switching in stochastic models of commodity prices an application to an optimal tree harvesting problem abstract this paper investigates whether a regime switching model of stochastic lumber prices is better for the analysis of optimal harvesting problems in forestry than a more traditional single regime model prices of lumber derivatives are used to calibrate a regime switching model with each of two regimes characterized by a different mean reverting process a single regime mean reverting process is also calibrated the value of a representative stand of trees and optimal harvesting prices are determined by specifying a hamilton jacobi bellman variational inequality which is solved for both pricing models using a implicit finite difference approach the regime switching model is found to more closely match the behavior of futures prices than the single regime model in addition analysis of a tree harvesting problem indicates significant differences in terms of land value and optimal harvest thresholds between the regime switching and single regime models

tax interaction effects environmental regulation and rule of thumb adjustments to social cost preexisting distortions in factor markets complicate the estimation of the social welfare effects of regulatory interventions the existence of these tax interaction effects ties suggests that general equilibrium ge approaches should be used to evaluate regulatory policies however formal ge analysis is not always feasible for the numerous environmental regulations proposed by federal state and local agencies the question addressed in this paper is whether an empirically based rule of thumb upward adjustment factor is appropriate to properly scale social cost estimates in environmental policy we argue that such rule of thumb adjustments are significantly less reliable than estimates based on a detailed general equilibrium analysis because of the uncertainty about both the magnitude and sign of the social cost distortion in addition to addressing this question the paper gives an overview of ties and their relevance to environmental policy

optimal forest rotation and land values under a borrowing constraint abstract this study relaxes the assumption of perfect capital markets in the classical faustmann forest rotation model a constraint on borrowing changes all the basic properties of optimal forest harvesting instead of a constant rotation period an infinite chain of rotations is determined by a nonlinear difference equation the rotation period evolves over time and approaches a stationary rotation in finite or infinite time the length of optimal rotation timber supply and the value of forest land depend on forest owner specific factors that are normally nonexistent in rotation problems the model explains several empirical findings that cause problems for the classical versions of the faustmann model

harvesting a renewable resource under uncertainty abstract this paper presents a theory of harvesting that allows for partial harvests and accounts for the risk of extinction for biological assets with size dependent stochastic growth the harvesting decision is formulated as a disinvestment problem in continuous time and generalized faustmann formulas are derived the probability of extinction is then analyzed for a wide class of growth functions an illustration based on the logistic brownian motion shows that both optimal biomass at harvest and harvest size do not vary monotonically with uncertainty more generally this paper illustrates the importance of properly accounting for barriers in stochastic investment problems

principles of stochastic dynamic optimization in resource management the continuous time case abstract a wide range of problems in economics agriculture and natural resource management have been analyzed using continuous time optimal control models where the state variables change over time in a stochastic manner using a firm level investment model and a model of environmental degradation this paper provides a concise introduction to continuous time stochastic control techniques the process used to derive the differential of a stochastic process is stressed and in turn is used to explain ito s lemma bellman s equation the hamilton jacobi equation the maximum principle and the expected dynamics of choice variables a basic extension of the dynamic duality literature is also provided where the hamilton jacobi equation is used to derive a stochastic and dynamic analogue of hotelling s lemma

informational efficiency of markets for stumpage comment in a study of the information efficiency of markets for stumpage in the southern united states washburn and binkley found that time series data on stumpage price if given on annual or quarterly bases reveal weak form information efficiency for stumpage markets from this they conclude that there can be no gain from using past price movements to play the market in timing timber harvests p 403 specifically they infer that the reservation price rules derived for optimal forest harvesting by norstrom lohmander and brazee and mendelsohn are not applicable to the management of southern pine timberlands

involuntary unemployment and environmental policy the double dividend hypothesis an environmental tax reform might bring about gains over and above improved environmental quality in particular if tax revenues from environmental taxes are used to reduce the tax on wage income positive employment effects can result in second best economies an efficiency wage model is used to analyze the impact of an ecological tax reform on involuntary unemployment the government controls emissions by selling emission permits employment of labor and wages are determined endogenously conditions are identified under which an environmental tax reform reduces unemployment and increases welfare

on the elasticities of harvesting rules abstract in this paper we rank the relative importance of the exogenous parameters upon the optimal harvesting size in a stochastic rotation problem we show that when the tree growth follows geometric brownian motion the harvesting size is most elastic to the harvesting cost followed by the interest rate and is least elastic to the parameters of tree growth similar ranking holds for the linear growth case in both cases the harvesting size is increasing and concave in the harvesting cost bounded between two parallel lines the harvesting decision is made according to a stochastic extension of the faustmann formula

harvest decisions and asset valuation for biological resources exhibiting size dependent stochastic growth optimal harvest rules and preharvest valuation procedures are derived for biological assets with stochastic size dependent growth in a stochastic price environment these issues are analyzed as continuous time optimal stopping problems both the single rotation and ongoing rotations problems are addressed the sensitivity of harvest and valuation rules is assessed the results are compared with those derived from a myopic look ahead procedure and with the corresponding findings for age dependent growth copyright 1990 by economics department of the university of pennsylvania and the osaka university institute of social and economic research association

the response of household consumption to income tax refunds a central implication of the life cycle or permanent income theory is that consumption should not respond to predictable fluctuations in income tests of this implication have yielded mixed results especially on micro data angus deaton 1992 martin browning and annamaria lusardi 1996 in large part this might be due to the difficulties of isolating the predictable component of income at the micro level most tests proceed by instrumenting for income but since the available instruments are typically poor such tests might be prejudiced against finding significant excess sensitivity of consumption to income john shea 1995 also it is not clear how closely the resulting econometric predictions of income coincide with agents actual expectations of income to avoid these difficulties this paper examines the response of household consumption to a particular type of income that is both predictable and transitory income tax refunds since a refund depends on events in the previous calendar year it is predictable income as regards consumption in the year of its receipt consequently under the life cycle theory consumption should not increase on receipt of a refund 2 in addition to testing the canonical model of consumption this paper provides estimates interpretable as the marginal propensity to consume mpc out of refunds since federal tax refunds now amount to over 80 billion per year averaging well over 1 000 per refund these estimates are of interest in themselves more generally they bear on the impact of even preannounced and temporary changes in fiscal policy the paper begins by surveying related studies in section i section ii describes the data the consumer expenditure survey cex which of the leading u s micro data sets has the most comprehensive coverage of expenditure the empirical specification is set out in section hi section iv reports the results and section v concludes

fiscal policy in general equilibrium this paper studies four classic fiscal policy experiments within a quantitatively restricted neoclassical model the authors main findings are as follows 1 permanent changes in government purchases can lead to short run and long run output multipliers that exceed one 2 permanent changes in government purchases induce larger effects than temporary changes 3 the financing decision is quantitatively more important than the resource cost of changes in government purchases and 4 public investment has dramatic effects on private output and investment these findings stem from important dynamic interactions of capital and labor absent in earlier equilibrium analyses of fiscal policy copyright 1993 by american economic association

a comparison of the ito and stratonovich formulations of problems in finance abstract a comparison of and the relationship between the ito and stratonovich formulations of stochastic integration is given it is argued that generally the ito formulation is appropriate for problems of finance and economics the black scholes option pricing problem is discussed in both frameworks with the ito formulation being shown to be clearly superior a finance example in which the stratonovich approach is simplest is also presented

optimal forest rotation when stumpage prices follow a diffusion process a key assumption in the faustmann rule for financial maturity is that stumpage prices are constant over time timber price series however exhibit wide fluctuations over time which this paper models as a lognormal diffusion process comparing the diffusion results modeled here to the fixed price faustmann results show 1 the prescribed rotation length is generally longer 2 computed stand values are higher using the diffusion model with the greatest divergence occurring when a stand is about the midpoint of a rotation 3 as the stumpage price volatility increases the gain in computed npv increases though in a nonlinear fashion

thinning and harvesting in stochastic forest models abstract this paper analyzes a stochastic forest growth model in which the manager is able to first thin the forest to promote better growth before harvesting both wicksell single thinning and harvesting cycle and faustmann on going rotation problems are considered the wicksell problem is analyzed by first restricting the class of decision times to thinning harvesting pairs that bound the growth away from infinity and imbedding the problem in an infinite dimensional linear program on a space of triplets of measures these measures capture the thinning and harvesting decisions along with the behavior of the growth process prior to harvest an auxiliary linear program then leads to a nonlinear optimization problem for which an optimal value and solution are determined the values of all the problems are be related through a set of inequalities the solution of the nonlinear problem determines random thinning and harvesting times for the single thinning and harvesting cycle which demonstrate the equality of the values of these various problems finally for the wicksell problem the unrestricted class of thinning and harvest times is shown to give the same value as the restricted class the faustmann on going thinning and harvesting rotation problem is reduced to a wicksell problem which then allows for the characterization of the value as the solution to a different nonlinear optimization problem the effects of the opportunity to thin the forest are illustrated on a mean reverting stochastic model

fiscal shocks and their consequences this paper investigates the response of hours worked and real wages to fiscal policy shocks in the post world war ii us we identify these shocks with exogenous changes in military purchases and argue that they lead to a persistent increase in government purchases and tax rates on capital and labor income and a persistent rise in aggregate hours worked as well as declines in real wages the shocks are also associated with short lived rises in aggregate investment and small movements in private consumption we describe and implement a methodology for assessing whether standard neoclassical models can account for the consequences of a fiscal policy shock simple versions of the neoclassical model can account for the qualitative effects of a fiscal shock once we allow for habit formation and investment adjustment costs the model can also account reasonably well for the quantitative effects of a fiscal shock

on the double dividend under imperfect competition we investigate whether and under which conditions a revenue neutral environmental tax reform may yield an employment double dividend i e an improvement of environmental quality and an increase in aggregate employment using a model with two market imperfections a rigid real wage and imperfect competition in one industry we show that an employment dividend is plausibly obtained however for countries where labor taxes are high and households spend a large share of their income in favor of environmentally harmful consumption goods a double dividend can nevertheless not be obtained for under these conditions environmental quality deteriorates

harvesting and recovery decisions under uncertainty abstract a stochastic forest rotation model in the faustmann tradition is presented and exemplified the model combines harvesting decisions with the potential to recover or clean up to restore the land after very unfavorable evolutions of the stochastic growth process uncertainty is shown to have a generally ambiguous effect on the optimal choice of investment strategy it is also shown how such models can be related to theory of optimal inventory control

alleviating unemployment the case for green tax reforms abstract it has been argued recently that imposing taxes on pollution produces additional tax revenues which can be used to replace labour taxes and thus reap a double dividend in the form of improving environmental quality and alleviating unemployment this paper analyses the employment effects of revenue neutral green tax reforms by focusing on the revenue recycling effect our model contains three features which are important when looking at the employment effects of green tax reforms first there is unemployment in equilibrium second wages are determined endogenously third various institutional arrangements for taxing unemployment benefits for the price indexation of unemployment benefits and the personal tax exemption are considered it is shown that these institutional arrangements are crucial for the effectiveness of green tax reforms a revenue neutral green tax reform will boost employment if unemployment benefits are nominally fixed and taxed at a lower rate than labour income employment actually falls if unemployment benefits are price indexed and taxed at the same rate a revenue neutral green tax reform which increases the personal tax credit will never increase employment

the dynamic behavior of efficient timber prices a simple theoreticalmodel of a tim consist ing of faustmann rotations evalubermarket finds that there exists a rational expecta ated at the mean of the price process tions equilibrium in which prices evolve according the central question addressed in this to a stationary a r 1 process simulations analyz e study is what is the appropriate model of a model with a more general representation of tim timber prices this is an important quesber stock dynamics implications for the optimal tion given the prescriptive nature of the harvesting literature are 1 market efficiency pro timber harvesting literature3 vides little justification for random walk prices 2 and evidence unit root tests used in previous studies to analyz e that the form of the price process strongly the informational efficiency of timber markets do influences the performance of a reservanot distinguish between efficient and inefficient tion price rule relative to the faustmann markets and 3 failure to recognize asymmetric rotation haight and holmes 1991 plandisturbances in time series analyses of historical tinga 1998 nonetheless most authors aptimber prices can lead to sub optimal harvesting pear to select the form of the price process rules

the effect of catastrophic risk on forest investment decisions abstract we analyze the effect of catastrophic risk on forest investment decisions by employing a forest level model where the output price is specified to follow a stochastic process we then incorporate a poisson jump process to reflect the occurrence of catastrophic events it is found that the presence of catastrophic risk always results in a reduced production value but an increased investment threshold for a forestry project however depending on the assumption regarding the option whether the right to invest can be maintained after the occurrence of such an event the degree and pattern of the effect are different

the stochastic rotation problem a generalization of faustmann s formula to stochastic forest growth abstract in the present paper we study the optimal cutting strategy 1 2 for an ongoing forest by using stochastic impulse control we show how faustmann s formula can be generalized to stochastic growing forests the paper extends and clarifies previous studies by miller and voltaire 1983 clarke and reed 1989 and reed and clarke 1990

risk aversion and optimal forest replanting a stochastic efficiency study abstract a new stochastic efficiency analysis approach called stochastic efficiency with respect to a function serf is applied to analyse optimal tree replanting on an area of recently harvested forest land serf partitions a set of risky alternative tree replanting strategies in terms of certainty equivalents ces for a specified range of attitudes to risk both the entailed risk and the forest owner s risk aversion are taken into account the forest owner s degree of risk aversion affects both the optimal tree replacement strategy and the reinvestment decision the degree of risk aversion also needs to be taken into account when designing policy measures to affect forest investment

on solving the multirotational timber harvesting problem with stochastic prices a linear complementarity formulation this article develops a two factor real options model of the harvesting decision over infinite rotations assuming a known stochastic price process and using a rigorous hamilton jacobi bellman methodology the harvesting problem is formulated as a linear complementarity problem that is solved numerically using a fully implicit finite difference method this approach is contrasted with the markov decision process models commonly used in the literature the model is used to estimate the value of a representative stand in ontario s boreal forest both when there is complete flexibility regarding harvesting time and when regulations dictate the harvesting date