no free ride to zero emissions simulating a region s need to implement its own zero emissions vehicle zev mandate to achieve 2050 ghg targets abstract the adoption of zero emission vehicles zevs is limited by a variety of barriers some are region specific e g availability of charging infrastructure while others are global in nature e g battery prices where improvements spill over between regions this study explores regional spillover effects and ghg impacts of strong zev focused policy specifically the zev mandate in place in ten u s states zev states which requires automakers to sell a minimum amount of zevs each year we use a dynamic technology adoption model to simulate passenger vehicle sectors in north america focusing on the case of one small region british columbia covering 0 7 of the market as potentially free riding off of zev states policy covering 23 of the market results indicate that free ridership is not effective even with the zev mandate driving very high sales in zev states british columbia cannot achieve significant zev adoption without also implementing its own zev mandate further for british columbia to meet its 2050 ghg targets it may need a zev mandate in addition to complementary climate policies pushing zevs to account for 40 93 of new vehicle sales in 2050 in short regions seeking low carbon transportation likely need to implement their own stringent policies

spatial competition in the network television industry we present an empirical study of spatial competition and a methodology to estimate demand for products with unobservable characteristics using panel data we estimate a discrete choice model with latent product attributes and unobserved heterogeneous consumer preferences our application of the methodology to the network television industry yields estimates that are consistent with experts views given our estimates we compute nash equilibria of a product location game and find that firms observed strategies such as the degree of product differentiation are generally optimal discrepancies between actual and optimal strategies reflect the networks adherence to rules of thumb and possible bounded rationality behavior copyright 2001 by the rand corporation

battery electric vehicles looking behind to move forward abstract it is getting increasingly crucial for policymakers to acquire reliable price forecasts for battery electric vehicles bevs to make choices and set priorities here we examine the prospects for the wide deployment of bevs following an ex post analysis of their learning rate and an ex ante forecast of their price up to 2040 we make a clear distinction between the mainstream of bevs and a hypothetical group of bevs that are technically on a par with internal combustion vehicles icvs to do so we introduce a new index in which the driving range and max speed of a vehicle are coupled together i e the mobility diffusion coefficient we highlight different shares of battery packs i e 19 1 and the ensemble of electrification components e g battery pack electric motor power electronics i e electrification cost 52 2 in the price of a bev our price projections suggest that there is no prospect of breakeven between bevs and icvs before 2040 for both groups of bevs because the current learning rates of 9 2 and 15 1 for the price and electrification costs respectively of bevs strong and long term support from policymakers is required to ensure competitiveness of bevs with icvs in the near future

the role of brand image and product characteristics on firms entry and oem decisions we investigate the optimal market entry and original equipment manufacturer oem decisions of a firm facing a market in which firms brands can be horizontally differentiated and products can be vertically differentiated the entrant might sell under its own brand and compete with an incumbent become a supplier to the incumbent or both findings reveal that when consumers perceive the firms are horizontally and vertically differentiated the entrant profits by simultaneously entering the market and establishing an oem arrangement with the incumbent in such competitive scenarios both buyer and seller increase profits by agreeing on wholesale prices that are not too low which softens both horizontal and vertical conflict between the firms findings also show that the incumbent may prefer to pay high wholesale prices to the entrant even if the incumbent had the option to source the product independently at a lower marginal cost when firms have the capability of producing each other s product lines su

on the electrification of road transport learning rates and price forecasts for hybrid electric and battery electric vehicles abstract hybrid electric vehicles hevs and battery electric vehicles bevs are currently more expensive than conventional passenger cars but may become cheaper due to technological learning here we obtain insight into the prospects of future price decline by establishing ex post learning rates for hevs and ex ante price forecasts for hevs and bevs since 1997 hevs have shown a robust decline in their price and price differential at learning rates of 7 2 and 23 5 respectively by 2010 hevs were only 31 22 2010 kw 1 more expensive than conventional cars mass produced bevs are currently introduced into the market at prices of 479 171 2010 kw 1 which is 285 213 2010 kw 1 and 316 209 2010 kw 1 more expensive than hevs and conventional cars our forecast suggests that price breakeven with these vehicles may only be achieved by 2026 and 2032 when 50 and 80 million bevs respectively would have been produced worldwide we estimate that bevs may require until then global learning investments of 100 150 billion which is less than the global subsidies for fossil fuel consumption paid in 2009 these findings suggest that hevs including plug in hevs could become the dominant vehicle technology in the next two decades while bevs may require long term policy support

research on the motion picture industry state of the art and new directions off the beaten track away from theatrical release the motion picture industry has been subject of extensive academic research over the last decades however most scholars focused on the u s theatrical motion picture market the number of research activities regarding even more profitable release windows such as home video or television has been substantially lower although international distribution is essential for a motion picture project to break even there has been little significant re search on most other markets this paper aims at summarizing the current state of research on the motion picture industry particularly from marketing and management perspective revealing research gaps and proposing recommendations for future research endeavors therefore a three pillar scheme is developed to systemize previous findings research on intraorganizational decision making contractual relationships between national stakeholders and international market competition are differentiated since these insights are mainly derived from u s theatrical exhibition they can hardly be applied to other markets and exhibition windows thus potential research areas are identified to expand knowledge of posttheatrical and international markets

technological discontinuities and the challenge for incumbent firms destruction disruption or creative accumulation the creative destruction of existing industries as a consequence of discontinuous technological change is a central theme in the literature on industrial innovation and technological development established competence based and market based explanations of this phenomenon argue that incumbents are seriously challenged only by competence destroying or disruptive innovations which make their existing knowledge base or business models obsolete and leave them vulnerable to attacks from new entrants this paper challenges these arguments with detailed empirical analyses of the automotive and gas turbine industries we demonstrate that these explanations overestimate the ability of new entrants to destroy and disrupt established industries and underestimate the capacity of incumbents to perceive the potential of new technologies and integrate them with existing capabilities moreover we show how intense competition in the wake of technological discontinuities driven entirely by incumbents may instead result in late industry shakeouts we develop and extend the notion of creative accumulation as a way of conceptualizing the innovating capacity of the incumbents that appear to master such turbulence specifically we argue that creative accumulation requires firms to handle a triple challenge of simultaneously a fine tuning and evolving existing technologies at a rapid pace b acquiring and developing new technologies and resources and c integrating novel and existing knowledge into superior products and solutions

biophysical assessments in evaluating industrial development an experience from taiwan freshwater aquaculture abstract herman e daly noted in 1992 that maintaining the scale of the physical economy within ecological capacity is vital in pursuing sustainability leading to the use of biophysical assessments as a central concept in sustainability analysis from the perspective of ecological economics accordingly this study provides an empirical support for the key role of biophysical assessments in sustainability analysis by presenting the pictures of taiwan freshwater aquaculture from monetary and biophysical perspectives the analytical results demonstrate that freshwater aquaculture contributes to taiwan s economic prosperity from a monetary perspective but causes land subsidence from the biophysical perspective results of this study also indicate the critical role of spatial dimension in biophysical assessments

testing for the presence of some features of increasing returns to adoption factors in energy system dynamics an analysis via the learning curve approach the purpose of this paper is to explain the sources of energy system lock in it presents a comparative analysis of the respective contributions of some features of increasing returns to adoption factors i e learning by doing learning by searching and returns to scale effects in explaining the technological change dynamics in the energy system the paper is technically based on a critical analysis of the learning curve approach econometric estimation of learning and scale effects inherent to seven energy technologies were performed by the use of several learning curve specifications these specifications permit to deal with some crucial issues related to the learning curve estimation which are associated with the problem of omitted variable bias the endogeneity effects and the choice of learning indicators results show that dynamic economies from learning effects coupled with static economies from scale effects are responsible for the lock in phenomena of the energy system they also show that the magnitude of such effects is correlated with the technology life cycle maturity in particular results point out that 1 the emerging technologies exhibit low learning rates associated with diseconomies of scale which are argued to be symptomatic of the outset of the deployment of new technologies characterized by diffusion barriers and high level of uncertainty 2 the evolving technologies present rather high learning rates meaning that they respond quickly to capacity expansion and r d activities development 3 conventional mature technologies display low learning rates but increasing returns to scale implying that they are characterized by a limited additional diffusion prospects

scale prices and biophysical assessments abstract in a recent forum on biophysical assessments a number of ecological economists expressed serious reservations about the use of prices to assess the appropriate scale of macroeconomic systems while such reservations are warranted the preference for biophysical assessments over prices indicates that many ecological economists are focussing on one notion of scale and neglecting another altogether there are two notions of scale that are critical to achieving sustainable development sd one is the maximum sustainable macroeconomic scale the other is the optimal macroeconomic scale the maximum sustainable scale is the largest macroeconomic scale that can be sustained by a throughput of matter energy that is within the ecosphere s regenerative and waste assimilative capacities the optimal scale is a preferable macroeconomic scale and is one that is not only sustainable but one that maximises the net benefits of economic activity biophysical assessments are needed to determine the maximum sustainable scale because ecological sustainability is a biophysical problem not an economic problem thus it is through biophysical assessments that the necessary restrictions on the incoming resource flow can be calculated and imposed however since the achievement of an optimal macroeconomic scale is an economic problem albeit a constrained economic problem relative prices are required to efficiently allocate the sustainable resource flow so the macroeconomy can adjust to the optimum failure to recognise the two notions of scale and the most appropriate means of their assessment is likely to thwart rather than advance the movement toward sd

long term diffusion dynamics of alternative fuel vehicles in brazil abstract alternative fuel vehicles afv are a promising alternative to reduce greenhouse gas emissions in the transportation sector and ultimately to contribute to a more sustainable society within the current commitments of the brazilian government to international agreements in terms of emissions reductions by 2030 some new policies have been implemented in order to incentivize the diffusion of afv in the country yet how will these policies contribute to the goal of increasing its fleet in the long term how long will it take and what are the differences if any among the policies in terms of their effectiveness are questions that remain unanswered in this sense the main aim of this paper is to investigate the impact of public policies in the long term diffusion dynamics of afv in brazil in order to do so a system dynamics model is developed based on the generalized bass diffusion model the cobb douglas function and the learning curve theory the model is used to test four different policies and some uncertainties related to i the exemption of the import duty ii the reduction of the motor vehicle property tax iii the exemption of the tax on manufacturing goods and iv a banning regulation for internal combustion engine vehicles in the long term the results highlight the importance of the current incentive policies but at the same time call for reinforcing efforts in order to increase the afv fleet to significant values by 2030 conversely the banning regulation obtains a higher diffusion rate but only achieves significant values by 2060 the paper concludes by showing the main contributions and policy implications of the effectiveness of the four policies studied as well as some suggestions for future work

an economic perspective on experience curves and dynamic economies in renewable energy technologies this paper analyzes dynamic economies in renewable energy technologies the paper has two contributions the first is to test the robustness of experience in solar photovoltaic solar thermal and wind energy to the addition of an explicit time trend which has been done in experience studies for other industries but not for renewable energy technologies estimation is carried out on the assumption that cumulative capacity industry production average firm production and electricity generation affect experience and thus the fall in price the second contribution is to test the impact of r d on price reduction in general cumulative experience is found to be highly statistically significant when estimated alone and highly statistically insignificant when time is added to the model the effect of r d is small and statistically significant in solar photovoltaic technology and statistically insignificant in solar thermal and wind technologies

assessing the progress toward lower priced long range battery electric vehicles abstract the aim of this study is to show the progress in attributes and prices of battery electric vehicles bev and to analyse in which market segments long range bev can be produced at comparable cost to conventional cars we assess 48 models available to consumers since 1997 collecting data on attributes weight and vehicle prices we also provide an analysis of recent progress in battery pack costs based on this data the share of bev vehicle price that is related to the battery pack is modelled to illustrate future progress we estimate when it is possible to produce a bev with a 200 mile range in a given price percentile we find that the price percentile where the price of a bev is comparable to conventional cars changes in a nonlinear way when battery pack costs fall below 200 250 usd kwh furthermore we show that battery pack costs of 150 usd kwh could imply that production costs of a bev with a 200 mile range are cost competitive for almost 50 of the us car market segments by 2020 finally the most critical conditions for this development are discussed and assessed by sensitivity analysis applying conservative values to our model

technological learning and renewable energy costs implications for us renewable energy policy abstract this paper analyzes the relationship between current renewable energy technology costs and cumulative production research development and demonstration expenditures and other institutional influences combining the theoretical framework of learning by doing and developments in learning by searching with the fields of organizational learning and institutional economics offers a complete methodological framework to examine the underlying capital cost trajectory when developing electricity cost estimates used in energy policy planning models sensitivities of the learning rates for global wind and solar photovoltaic technologies to changes in the model parameters are tested the implications of the results indicate that institutional policy instruments play an important role for these technologies to achieve cost reductions and further market adoption

cost effectiveness as energy policy mechanisms the paradox of technology neutral and technology specific policies in the short and long term when choosing policy mechanisms to design and deploy energy policies policymakers typically seek cost effective ones linking cost effectiveness to the lowest cost of support for res e generation and or consumer costs the objectives of this paper are to analyze the cost effectiveness of renewable portfolio standards rps feed in tariffs fit and auctions in the short and long term considering both technology neutral and technology specific approaches results show that rps and auctions are more cost effective than feed in tariffs fit in the short term if cost effectiveness is defined as minimizing consumer costs also if one or more emerging technologies with higher levelized life cycle costs lcc low cumulative production and high experience elasticity are considered in the pool of res e policy design a technology neutral approach in the short term could lock out these emerging technologies avoiding a long term lcc reduction in this case a technology specific policy used in the short term would reflect lower total generation policy costs in the long term if compared with a technology neutral policy in both short and long term this paper calls this phenomenon the paradox of technology neutral and technology specific policies in the long term considering the results this paper suggests a mix of technology neutral and technology specific policies using rps or auction mechanisms to promote res e

economic indicators of resource scarcity a critical essay abstract the theoretical arguments of the conceptual and empirical literature on economic indicators of long run resource scarcity are logically flawed if resource allocators were informed of the nature of resource scarcity their behavior and the economic indicators it generates would reflect the scarcity but if they were so informed we could simply ask them if resources were scarce if they are not informed their behavior and economic indicators are as likely to indicate their ignorance as the reality unfortunately there is no way of knowing whether they are informed or not unless we already know whether resources are scarce

a reply to a comment on is having more channels really better a model of competition among commercial television broadcasters liu et al liu y d s putler c b weinberg 2004 is having more channels really better a model of competition among commercial television broadcasters marketing sci 23 1 120 133 examine the television broadcast industry using a model in which profit maximizing broadcasters seek to gain viewers by choosing the type of program to offer and by spending money to set program quality allowing broadcasters to sell access to those viewers through inserted advertisements at a fixed rate per viewer wu and chou wu c s chou 2006 commentary on is having more channels really better a model of competition among commercial television broadcasters marketing sci 25 5 541 545 argue that the duopoly result for a certain range of the cost parameter in liu et al is not a pure strategy nash equilibrium they further propose some modifications to the original model to restore liu et al s results in this reply we demonstrate how a single strategy not included in the strategy space of the liu et al duopoly model leads to the difference between our analysis and that of wu and chou while we had intended to rule out this strategy the text was not entirely clear on this issue wu and chou s comment provides an opportunity to clarify the situation we provide both empirical and theoretical support for excluding this strategy which allows us to focus on the more plausible competitive situations in television broadcasting we also reply to wu and chou s other comments on several issues such as the relative importance of program type versus quality

representing induced technological change in models for climate policy analysis induced technological change itc whereby the relative price effects of reducing greenhouse gas emissions stimulate innovation that mitigates the cost of abatement is both tantalizing to decision makers and challenging to represent in the computational economic and engineering models used to analyze climate change policy this overview reconciles the divergent views of technology and technological change within different types of models elucidates the theoretical underpinnings of itc introduces the reader to the techniques of their practical implementation and evaluates the implications for models results

a comment on is having more channels really better a model of competition among commercial television broadcasters this paper shows that the analysis of liu et al 2004 contains a substantive error the asserted pure strategy nash equilibrium leading to their theorems 1 and 2 is really not an equilibrium we show that in their model either pure strategy nash equilibria do not exist or unlike their asserted main result when a pure strategy equilibrium exists increasing the number of commercial television broadcasters does not result in lower quality programs possible modifications of liu et al s model that may help restore the desired result are discussed

a just and efficient reduction of resource throughput to optimum abstract resource throughput in the economy e g of energy or materials must be progressively reduced by at least one order of magnitude to achieve an optimal level although this would solve the resource distribution conflict between the generations it would also aggravate the resource distribution conflict between persons of the same generation it is shown here that a solution to these two conflicts and efficient resource allocation are only possible if resource certificates are distributed to consumers free of charge and traded between them this paper builds on and integrates ideas developed in h daly s daly h e 1992 allocation distribution and scale towards an economics that is efficient just and sustainable ecological economics 6 185 193 article on allocation distribution and scale adding insights from the ecological footprint concept to propose a mechanism for facilitating intergenerational equity and drastically reducing resource throughput basically the mechanism involves rationing throughput equitably internalizing environmental and social externalities and substituting labour for resource use this can be achieved almost without a drop in prosperity both unemployment and dependence on scarce resources decline

note competitive price and positioning strategies brand positioning and brand pricing are important strategic decisions for marketing managers such decisions are interrelated and depend upon competitive brand positions and prices however any unilateral decisions may encourage repositioning and price adjustment by competitors thus leading to either new market equilibria or a price positioning war this paper examines such price and positioning decisions in a competitive environment by extending the defender consumer model to more complex equilibria we assume that the brands are already in the market and that positions are sticky in the sense that brands cannot leapfrog one another among the insights for such incumbent brands are if prices are symmetric and held constant firms seek to reposition toward the center of the market but price advantages by central firms can mediate that central tendency such that an equilibrium exists with positive profits if brand positions are held constant the nash equilibria for prices exist and are unique and category profits the sum of brand profits are maximized for maximum brand differentiation for two and three brand markets the subgame perfect nash equilibrium where positioning decisions are made with foresight on the price equilibria causes firms to unilaterally seek maximum brand differentiation but for four or more brands greater foresight and or cooperation appears necessary to reach the point of maximum brand differentiation these results apply where the defender consumer model is an exact description of consumer response and where the competitive reaction assumptions hold in any empirical situation such forces might be softened resulting in differentiated but not maximally differentiated brands

technological change in energy systems learning curves logistic curves and input output coefficients abstract learning curves have recently been widely adopted in climate economy models to incorporate endogenous change of energy technologies replacing the conventional assumption of an autonomous energy efficiency improvement however there has been little consideration of the credibility of the learning curve the current trend that many important energy and climate change policy analyses rely on the learning curve means that it is of great importance to critically examine the basis for learning curves here we analyse the use of learning curves in energy technology usually implemented as a simple power function we find that the learning curve cannot separate the effects of price and technological change cannot reflect continuous and qualitative change of both conventional and emerging energy technologies cannot help to determine the time paths of technological investment and misses the central role of r d activity in driving technological change we argue that a logistic curve of improving performance modified to include r d activity as a driving variable can better describe the cost reductions in energy technologies furthermore we demonstrate that the top down leontief technology can incorporate the bottom up technologies that improve along either the learning curve or the logistic curve through changing input output coefficients an application to uk wind power illustrates that the logistic curve fits the observed data better and implies greater potential for cost reduction than the learning curve does

quantitative study on long term global solar photovoltaic market abstract this paper analyzes the relationship between the declines in solar photovoltaic pv module costs and cumulative production silicon prices supply demand imbalance and the presence of lower cost chinese products in global pv market using learning curve model state of market development and its connection with learning is also examined results indicate that learning effect is best measured when supplementing output with silicon prices in the analysis learning rate lr diminishes over the time periods examined thereby suggesting the declining of progress as market reaches maturity the outcomes from the learning curve analysis are subsequently applied to project future uptake of pv worldwide module and electricity costs till 2035 demand for pv is anticipated to remain robust with cumulative installed capacity worldwide projected to reach 659 gw by 2035 at the same time module cost is estimated to decline from 3 8 w in 2006 to 1 78 w in 2035 a reduction of over 50 relative to 2006 level unit cost of electricity from pv is predicted to be in the range of 0 13 kwh to 0 17 kwh by 2035 for the three scenarios analyzed

has australia surpassed its optimal macroeconomic scale finding out with the aid of benefit and cost accounts and a sustainable net benefit index abstract the sustainable economic welfare of a nation depends largely on the sustainable net benefits the macroeconomy confers to its citizens for this reason an optimal macroeconomic scale can be considered one where the physical scale of the macroeconomy and the qualitative nature of the stock of wealth it comprises maximises a nation s sustainable net benefits the corollary of this definition is thus the physical scale of the macroeconomy should grow only if in the process the sustainable net benefits of a nation increase it should cease to grow once sustainable net benefits are maximised whilst it is one thing to promote an optimal macroeconomic scale it is another entirely to gain an appreciation of the sustainable net benefits yielded by the macroeconomy gaining such an appreciation constitutes the central aim of this paper with the assistance of two separate benefit and cost accounts to replace gross domestic product gdp a sustainable net benefit index is constructed for australia for the period 1966 1967 to 1994 1995 the index particularly at the per capita level indicates that economic welfare in australia is declining i e the average australian is getting poorer despite per capita real gdp increasing the index therefore suggests that the scale of the australian macroeconomy has probably well exceeded the optimum

economic growth international competitiveness and environmental protection r d and innovation strategies with the warm model abstract it is often argued that policies designed to protect the environment may harm economic growth moreover if introduced unilaterally by a given country they may reduce the competitiveness of domestic firms these arguments are generally based on the assumption that environmental protection has to be achieved through the introduction of emission charges e g a carbon tax however three issues need to be raised first the tax is not the only policy instrument and is not the most efficient one that can be used to reduce polluting emissions secondly even when a tax policy is implemented it is important to assess the feedback effects induced by recycling the tax revenue thirdly and most importantly the role of technical progress cannot be neglected therefore there may exist a policy mix that provides firms with the correct incentives to adopt energy saving technologies and to invest in environment friendly r d the first two issues have partly been explored both in the theoretical and empirical literature the third issue i e the role of incentives to technical progress still lacks adequate quantitative assessment this is why a new model has been developed which endogenizes technical progress and its effects and feedbacks on economic energy and environmental variables using warm an econometric general equilibrium model for the european union and for each member country this paper presents simulation results up to 2015 of the effects of some industrial environmental policies which are aimed at protecting the environment without necessarily damaging competitiveness and economic growth the results show that policies that stimulate environmental r d technological innovation and diffusion may provide firms with the correct incentives to avoid damaging the environment while preserving their competitiveness in the market moreover such a policy based both on r d subsidies and on innovation incentives may not worsen the public sector budget balance as a result of the positive effects on economic growth

technical change dynamics evidence from the emerging renewable energy technologies abstract this paper explores the respective contributions of the effects of learning and returns to scale in the capital costs reduction pattern experienced by renewables causality analysis and econometric estimation of learning curves are performed on two emerging renewable energy technologies namely pv and wind learning effects appear as an essential driving force a result which concurs with the widely acknowledged importance of experience in technical progress inherent to economic growth the existence of non constant and flexible returns to scale are further highlighted their effect on diffusion dynamics is shown to be potentially considerable particularly at the outset of innovation deployment however returns to scale are suggested to be constant in the long term institutional commitment in supporting innovation therefore seems justified both on the basis of the occurrence of learning effects and diseconomies of scale these findings appear to be essential to the dynamics of innovation diffusion and market structure

an optimization model for renewable energy generation and its application in china a perspective of maximum utilization in response to climate change china s power industry is undertaking the task of reducing carbon emissions renewable energy generation has become an important option for the government and state grid companies it is important to know the maximum possible capacities of renewable energy generation from its different sources in order to plan the construction of the power grid in the future in this paper several important factors affecting the development of renewable energy generation are identified through a review of the existing literature such as cost technical maturity and so on and analyzed combined with the learning curve model the technology diffusion model and expectations about future economic development in china a new model the renewable energy optimization model reom is developed to analyze the development of three renewable energy sources wind power solar power and biomass power from 2009 to 2020 results show that 1 the maximum installed capacities of wind power solar power and biomass power will reach 233321 26680 and 35506 mw in 2020 2 from 2009 to 2020 biomass power will develop rapidly at the early stage while wind power is developed massively at the final stage and solar power has relatively stable growth 3 due to the added capacity in the early periods the unit investment cost of solar power shows a large decline which is good for its following scale development 4 the investment ratio constraint has a large effect on the development of wind power while the constraint of on grid proportion of renewable energy generation has a significant effect on the development of wind power and solar power the results have important policy implications for long term energy planning in developing countries such as china and india

conservation of mass and instability in a dynamic economy environment system abstract this paper considers a variant of the neumann leontief sraffa general equilibrium models in the context of a jointly determined economy environment system subject to a conversation of mass condition it shows that the conservation of mass contradicts the free disposal free gifts and non innovation assumptions of such models that an expanding economy will be associated with continuous disequilibrating change in the material transformations of both economy and environment and that this change is uncontrollable through the price system

technological learning in energy environment economy modelling a survey abstract this paper aims at providing an overview and a critical analysis of the technological learning concept and its incorporation in energy environment economy models a special emphasis is put on surveying and discussing through the so called learning curve both studies estimating learning rates in the energy field and studies incorporating endogenous technological learning in bottom up and top down models the survey of learning rate estimations gives special attention to interpreting and explaining the sources of variability of estimated rates which is shown to be mainly inherent in r d expenditures the problem of omitted variable bias the endogeneity relationship and the role of spillovers large scale models survey show that despite some methodological and computational complexity related to the non linearity and the non convexity associated with the learning curve incorporation results of the numerous modelling experiments give several new insights with regard to the analysis of the prospects of specific technological options and their cost decrease potential bottom up models and with regard to the analysis of strategic considerations especially inherent in the innovation and energy diffusion process in particular the energy sector s endogenous responses to environment policy instruments top down models

a review of learning rates for electricity supply technologies a variety of mathematical models have been proposed to characterize and quantify the dependency of electricity supply technology costs on various drivers of technological change the most prevalent model form called a learning curve or experience curve is a log linear equation relating the unit cost of a technology to its cumulative installed capacity or electricity generated this one factor model is also the most common method used to represent endogenous technical change in large scale energy economic models that inform energy planning and policy analysis a characteristic parameter is the learning rate defined as the fractional reduction in cost for each doubling of cumulative production or capacity in this paper a literature review of the learning rates reported for 11 power generation technologies employing an array of fossil fuels nuclear and renewable energy sources is presented the review also includes multi factor models proposed for some energy technologies especially two factor models relating cost to cumulative expenditures for research and development r d as well as the cumulative installed capacity or electricity production of a technology for all technologies studied we found substantial variability as much as an order of magnitude in reported learning rates across different studies such variability is not readily explained by systematic differences in the time intervals geographic regions choice of independent variable or other parameters of each study this uncertainty in learning rates together with other limitations of current learning curve formulations suggests the need for much more careful and systematic examination of the influence of how different factors and assumptions affect policy relevant outcomes related to the future choice and cost of electricity supply and other energy technologies

degrowth taking stock and reviewing an emerging academic paradigm degrowth has evolved within a decade from an activist movement into a multi disciplinary academic paradigm however an overview taking stock of the peer refereed degrowth literature is yet missing here we review 91 articles that were published between 2006 and 2015 we find that the academic degrowth discourse occupies a small but expanding niche at the intersection of social and applied environmental sciences the discourse is shaped by authors from high income mainly mediterranean countries until 2012 articles largely constitute conceptual essays endorsed by normative claims more recently degrowth has branched out into modelling empirical assessments and the study of concrete implementations authors tend to agree in that economic growth cannot be sustained ad infinitum on a resource constraint planet and that degrowth requires far reaching societal change whether degrowth should be considered as a collectively consented choice or an environmentally imposed inevitability constitutes a major debate among degrowth thinkers we argue that the academic discourse could benefit from rigid hypotheses testing through input output modelling material flow analysis life cycle assessments or social surveys by analyzing the potentials for non market value creation and identifying concrete well being benefits the degrowth discourse could receive wider public support and contribute to a paradigmatic change in the social sciences

trade policy and learning by doing the case of semiconductors abstract the study examines the role of learning by doing for production of different types of semiconductors and how this affects the dynamics of market structure for erasable programmable read only memories eproms the learning curve determines aggregate market dynamics whereas for dynamic random access memories drams economies of scale seem to be more important these results are compared with some stylised facts for eproms persistence of leadership in product innovation could be observed whereas for drams there was leap frogging in product innovation moreover scope for vertical product differentiation is more enhanced for eproms and price competition is less intense these findings are then related to the problem of identifying the appropriate trade policies in oligopolistic industries the analysis concerns the antidumping actions undertaken by the european commission it is shown how markets enjoying similar patterns of protection have a completely different evolution of market shares for european producers the conclusion for strategic trade policy is that industry specific features matter crucially

national natural capital accounting with the ecological footprint concept abstract there is a growing consensus among natural and social scientists that sustainability depends on maintaining natural capital however progress to put this ecological condition to practice has been slow not least because of the inability of making these objectives measurable therefore to overcome this obstacle assessment frameworks for natural capital are needed this study presents a simple framework for national and global natural capital accounting it demonstrates using the example of italy an accounting framework which tracks national economies energy and resource throughput and translates them into biologically productive areas necessary to produce these flows this calculation has been applied to over 52 countries with this framework based on the ecological footprint concept human consumption can be compared with natural capital production at the global and national level using existing data

the impact of r d on innovation for wind energy in denmark germany and the united kingdom this paper examines the impact of public research and development r d support on cost reducing innovation for wind turbine farms in denmark germany and the united kingdom uk first we survey the literature in this field the literature indicates that in denmark r d policy has been more successful than in germany or the uk in promoting innovation of wind turbines furthermore such studies point out that subsidy induced capacity expansions were more effective in the uk and denmark in promoting cost reducing innovation than in germany the second part of the paper describes the quantitative analysis of the impact of r d and capacity expansion on innovation this is calculated using the two factor learning curve 2flc model in which investment cost reductions are explained by cumulative capacity and the r d based knowledge stock time series data were collected for the three countries and organized as a panel data set the parameters of the 2flc model were estimated focusing on the homogeneity and heterogeneity of the parameters across countries we arrived at robust estimations of a learning by doing rate of 5 4 and a learning by searching rate of 12 6 the analysis underlines the homogeneity of the learning parameters enhancing the validity of the 2flc formulation

understanding wind turbine price trends in the u s over the past decade understanding wind turbine price trends in the u s over the past decade mark bolinger and ryan wiser lawrence berkeley national laboratory pre print of article submitted to energy policy abstract on a per kw basis wind turbine prices in the u s have declined by nearly one third on average since 2008 after having previously doubled over the period from 2002 through 2008 these two substantial and opposing trends over the past decade and particularly the earlier price doubling run counter to the smooth gradually declining cost trajectories predicted by standard learning curve theory taking a bottom up approach we examine seven possible drivers of wind turbine prices in the u s with the goal of estimating the degree to which each contributed to the doubling in turbine prices from 2002 through 2008 as well as the subsequent decline in prices through 2010 in aggregate these seven drivers which include changes in labor costs warranty provisions manufacturer profitability turbine scaling raw materials prices energy prices and foreign exchange rates explain from 70 to 90 depending on the year of empirically observed wind turbine price movements in the u s through 2010 turbine scaling is found to have been the largest single contributor to the price doubling through 2008 although the incremental cost of scaling has been justified by greater energy capture resulting in a lower cost of wind generation acknowledgments the work described in this article was funded by the u s department of energy s wind water power program within the office of energy efficiency and renewable energy under contract no de ac02 05ch11231 disclaimer this document was prepared as an account of work sponsored by the united states government while this document is believed to contain correct information neither the united states government nor any agency thereof nor the regents of the university of california nor any of their employees makes any warranty express or implied or assumes any legal responsibility for the accuracy completeness or usefulness of any information apparatus product or process disclosed or represents that its use would not infringe privately owned rights reference herein to any specific commercial product process or service by its trade name trademark manufacturer or otherwise does not necessarily constitute or imply its endorsement recommendation or favoring by the united states government or any agency thereof or the regents of the university of california the views and opinions of authors expressed herein do not necessarily state or reflect those of the united states government or any agency thereof or the regents of the university of california ernest orlando lawrence berkeley national laboratory is an equal opportunity employer

an industry equilibrium analysis of downstream vertical integration this paper investigates the effect of product substitutability on nash equilibrium distribution structures in a duopoly where each manufacturer distributes its goods through a single exclusive retailer which may be either a franchised outlet or a factory store static linear demand and cost functions are assumed and a number of rules about players expectations of competitors behavior are examined it is found that for most specifications product substitutability does influence the equilibrium distribution structure for low degrees of substitutability each manufacturer will distribute its product through a company store for more highly competitive goods manufacturers will be more likely to use a decentralized distribution system this article was originally published in marketing science volume 2 issue 2 pages 161 191 in 1983

is having more channels really better a model of competition among commercial television broadcasters competitive behavior in commercial television broadcasting is modeled to examine program choice and the effects of more channels being available on firm strategy specifically broadcasters compete by selecting both the type and quality level of a program to offer but do not compete on price we obtain five major results first a comparison of monopoly and duopoly markets indicates that broadcasters in an industry with a larger number of competitors may provide programs of lower quality compared to broadcasters in an industry with a smaller number second in terms of viewer welfare having more channels available is not necessarily better third broadcasters tend to choose an intermediate level of differentiation in terms of the types of programs they provide resulting in a counterprogramming strategy in other words avoidance of price competition is not required for competitors to differentiate themselves from each other fourth if one broadcaster starts the evening with a higher quality higher rated program than its competitor its second program should also be of higher quality finally a broadcaster s first program should be of equal or higher quality than its second program put another way it always behooves a broadcaster to lead with its best

a flexible assurance bonding system for improved environmental management abstract current methods of regulating activities that are known or suspected to be environmentally danaging are not working well they induce legal confrontation obfuscation and government intrusion into the inner workings of firms they tend to suppress technical and social innovation aimed at long term solutions they do not mesh well with the market signals that firms use to make decisions this paper discusses some of the underlying reasons for this problem and outlines a flexible environmental assurance bonding system designed to incorporate environmental criteria and uncertainty into the market system and to induce positive environmental technological innovation in addition to direct charges for known environmental damages an assurance bond equal to the current best estimate of the largest potential future environmental damages would be levied and kept in an interest bearing escrow account the bond plus a portion of the interest would be returned if and only if the firm could prove that the suspected damages had not occured or would not occur if damages did occur the bond would be used to rehabilitate or repair the environment and to compensate injured parties by requiring the users of environmental resources to post a bond adequate to cover potential future environmental damages with the possibility for refunds the burden of proof is shifted from the public to the resource user and a strong economic incentive is provided to research the true costs of environmentally innovative activities and to develop innovative cost effective pollution control technologies

predicting competitive response to a major policy change combining game theoretic and empirical analyses this research uses procter gamble s value pricing initiative as a context for testing whether actual competitor and retailer response to a major policy change can be predicted using a game theoretic model we first estimate demand functions for p g and competitor brands from the period before value pricing was initiated we then formulate a dynamic manufacturer retailer stackelberg model that includes p g a national brand competitor and a retailer the model takes p g s move as given and prescribes the price and promotion response of the competitors and the retailer we substitute the estimated demand parameters into the model to obtain prescriptions for each competitor and the retailer and see whether these prescriptions are related to the actual response we find that the dynamic game theoretic model calibrated with empirical estimates of demand parameters has significant predictive power we also test the predictive power of two benchmark models the first is based on the reaction function approach of leeflang and wittink leeflang peter s h wittink dick r 1992 diagnosing competitive reactions using aggregated scanner data internat j res marketing9 39 57 and the second is a simplification of our dynamic model where the retailer is not strategic the dynamic game theoretic model performs better than either benchmark

a hierarchical cost learning model for developing wind energy infrastructures renewable energy has been increasingly promoted and used to substitute non renewable fossil fuels which cause negative effects on the environment the taiwan statute for renewable energy development has regulated and promoted renewable energy since 2009 a feed in tariff fit for renewable energy is one of the incentives that the government uses to promote the installation of green power generation facilities the price of the electricity feed in tariff is based on the current and future costs of renewable energy generation when analyzing cost trends for renewable energy installation many researchers use a single factor cost learning curve model however past studies indicate that there are multiple factors affecting the overall cost of installing renewable energy hence this research develops a hierarchical installation cost learning model which considers multiple factors to accurately model and forecast wind energy development this research uses wind power development data from taiwan as a case study we identify the cost factors evaluate the learning effects and compare the hierarchical learning curve model to the basic non hierarchical learning curve model the research results show an improved fit between the hierarchical model and the actual data when compared to the basic learning model the study also provides new insights between the wind power learning progression of taiwan and three countries in europe

modeling movie life cycles and market share we examine box office sales in the context of a market share model this is accomplished by developing a combination of a sliding window logit model and a gamma diffusion pattern in a hierarchical bayes framework we show that accounting for the full choice set available every week not only increases the fit of weekly movie sales but also leads to parameter estimates that depict a richer picture of the movie industry we show that movie studios appear to have a good understanding of the products they produce knowing when to support them and when not to we also show that the effect of the number of opening week screens is overestimated in traditional models our research indicates that actors have a direct and directors an indirect effect on consumers movie choice releasing a movie contemporaneously with other movies of the same genre adversely affects box office performance all around releasing a movie against movies of the same motion picture association of america mpaa rating hurts its sales in the beginning but there is a displacement effect which leads to a less severe sales loss in the long run

endogenous technological change and the policy mix in renewable power generation abstract this paper introduces the renewable power generation module which complements large scale macro econometric input output models by introducing technological change endogenously into the model so far technological change in renewable power generation technologies is either set exogenously autonomous energy improving technological change or price induced in economic models introducing endogenous technological change is necessary to adequately analyze not only the direct effects but also the indirect effects on important macro economic indicators such as growth employment welfare and trade as well as their feedback to the electricity sector the development of pv module and wind turbine prices is modeled using learning curves at the global scale i e depending on global capacity installed of each of these technologies national capacity additions in turn depend on global prices national policies and economic development while demand pull policies enhance capacity installations technology push policies do not seem to have a significant direct influence the empirical results confirm the overshooting of pv installations in germany which can be slowed down by introducing degression of feed in tariffs over time

the learning curve and pricing in the chemical processing industries data on 37 chemical products are used to test a number of hypotheses about the learning curve and industrial price behavior the results document a strong and consistent learning effect learning is found to be a function of cumulated industry output and cumulated investment rather than calendar time standard economies of scale appear significant but small in magnitude relative to the learning effect variations in the slope of the learning curve are linked to differences in r d expenditures and capital intensity market concentration is found to be a strong influence on price flexibility and the timing of learningrelated price changes

degradacao ambiental e teoria economica algumas reflexoes sobre uma economia dos ecossistemas there are few consistent theoretical reflections on the suitability of economic instruments per se in facing the issue of natural capital degradation this paper presents some considerations about the relationship between environmental degradation and economic theory in a critical perspective the guiding assumption of the arguments is that the treatment given so far to the environment is largely reductionist which must necessarily be overcome by a transdisciplinary approach the sequencing of the ideas outlined converges to the need of building this new framework referred to here as economics of ecosystems

technological change in economic models of environmental policy a survey this paper provides an overview of the treatment of technological change in economic models of environmental policy numerous economic modeling studies have confirmed the sensitivity of mid and long run climate change mitigation cost and benefit projections to assumptions about technology costs in general technical progress is considered to be a noneconomic exogenous variable in global climate change modeling however there is overwhelming evidence that technological change is not an exogenous variable but to an important degree endogenous induced by needs and pressures hence some environmenteconomy models treat technological change as endogenous responding to socio economic variables three main elements in models of technological innovation are i corporate investment in research and development ii spillovers from r d and iii technology learning especially learning by doing the incorporation of induced technological change in different types of environmental economic models tends to reduce the costs of environmental policy accelerates abatement and may lead to positive spillover and negative leakage

technological change and the timing of mitigation measures we use a coupled carbon cycle and energy systems engineering model to analyze the future time path of carbon emissions under an illustrative co2 concentration stabilization limit of 550 ppm our findings confirm the emission pattern as found by wre global emissions rise initially pass through stabilization in order to decline in the second half of the 21st century we show that for a given co2 concentration target emission trajectories within an intertemporal optimization framework depend mainly on two factors the discount rate and the representation of technological change as either static or dynamic we obtain a similar near term emission time path as wre when using a model with static technology and a discount rate of 7 we obtain a trajectory with lower emissions in the near term when using a lower discount rate and or treating technology dynamics endogenously in the model we briefly outline a model that endogenizes technological change through learning curves we then compare differences in emission trajectories between alternative model formulations of technological change they are sufficiently small as to be of secondary importance when compared to treating co2 concentration stabilization as an inter temporal optimization problem or not whereas our results confirm the computational results of wre we arrive nonetheless at different policy conclusions if long term emission reduction is the goal we cannot follow business as usual even in the short term action needs to start now action does not necessarily mean aggressive short term emission reductions but rather enhanced r d and technology demonstration efforts that stimulate technological learning these are the necessary preconditions that long term reduction targets can be met with improved technology and at costs lower than today we close by pointing out two further critical issues uncertainty and the possible mismatch between the world of economic models and that of climate policy

evaluating the causes of cost reduction in photovoltaic modules abstract photovoltaic pv module costs have declined rapidly over forty years but the reasons remain elusive here we advance a conceptual framework and quantitative method for quantifying the causes of cost changes in a technology and apply it to pv modules our method begins with a cost model that breaks down cost into variables that changed over time cost change equations are then derived to quantify each variable s contribution we distinguish between changes observed in variables of the cost model which we term low level mechanisms of cost reduction and research and development learning by doing and scale economies which we refer to as high level mechanisms we find that increased module efficiency was the leading low level cause of cost reduction in 1980 2012 contributing almost 25 of the decline government funded and private r d was the most important high level mechanism over this period after 2001 however scale economies became a more significant cause of cost reduction approaching r d in importance policies that stimulate market growth have played a key role in enabling pv s cost reduction through privately funded r d and scale economies and to a lesser extent learning by doing the method presented here can be adapted to retrospectively or prospectively study many technologies and performance metrics besides cost

assessing the degrowth discourse a review and analysis of academic degrowth policy proposals abstract debates on ecological and social limits to economic growth and new ways to deal with resource scarcity without compromising human well being have re emerged in the last few years central to many of these is a call for a degrowth approach in this paper a framework is developed to support a systematic analysis of degrowth in the academic literature this article attempts to present a clearer notion of what the academic degrowth literature explores by identifying organising and analysing a set of proposals for action retrieved from a selection of articles the framework is applied to classify proposals according to their alignment to ecological economics policy objectives sustainable scale fair distribution and efficient allocation type of approach top down versus bottom up and geographical focus local national or international a total of 128 peer reviewed articles focused on degrowth were reviewed and 54 that include proposals for action were analysed the proposals identified align with three broad goals 1 reduce the environmental impact of human activities 2 redistribute income and wealth both within and between countries and 3 promote the transition from a materialistic to a convivial and participatory society the findings indicate that the majority of degrowth proposals are national top down approaches focusing on government as a major driver of change rather than local bottom up approaches as advocated by many degrowth proponents the most emphasised aspects in the degrowth literature are related to social equity closely followed by environmental sustainability topics such as population growth and the implications of degrowth for developing nations are largely neglected and represent an important area for future research moreover there is a need for a deeper analysis of how degrowth proposals would act in combination

sustainable growth criteria minimum benchmarks and scenarios for employment and the environment abstract the relationship of economic growth and environmental impact has spurred fierce debates between growth optimists referring to the phenomenon of the environmental kuznets curve and pessimists referring to the limits to growth however no operational set of simple criteria has been developed so far to assess the sustainability of a given growth pattern this is all the more true for measures combining environmental and social criteria the paper undertakes to sketch out such criteria and to assess them by applying them to transdiciplinary sustainability scenarios and model simulations with panta rhei one of the most complex models of the german economy theoretical considerations as well as the empirical work with the model demonstrate that there are indeed trade offs between economic growth and environmental impacts and a positive correlation of growth and employment nonetheless it is still possible to develop carefully orchestrated strategies that combine economic competitiveness low unemployment rates and an easing of the pressure on the environment social and technical innovation reduced working time a modernised social security system green taxes and salary increases proportional to labour productivity growth are essential parts of any such strategy the triple effectiveness of such strategies regarding environmental social and economic sustainability is demonstrated by the model runs

optimal policy supports for renewable energy technology development a dynamic programming model abstract policy support has played a significant role in driving the rapid development of renewable energy technologies rets this study constructed a dynamic programming model to derive the optimal policy supports for rets integrating both supply and demand sides the sensitivity of policy performance on the cost and price elasticities of ret diffusion was also analyzed the results show that policy supports could be a main force for ret development in their initial periods in the long run policy makers need to decrease the support level faster than the decrease in ret cost to maintain a high policy efficiency further improving the efficiency of policy is possible considering the influences of technical change on ret development

the optimal subsidy on electric vehicles in german metropolitan areas a spatial general equilibrium analysis abstract e mobility and diffusion of electric vehicles have become a major policy issue in many countries for example the german federal government pursues the strategy of achieving one million electric vehicles by 2020 in this paper we examine whether it is optimal to subsidize the use of electric vehicles by granting electric power subsidies and how large the corresponding optimal rate is we first analytically derive the optimal power tax in a spatial model of a city with two zones where commuting carbon emissions endogenous labor supply fuel and power taxes are considered it is shown that in a spatial urban environment the optimal tax rate depends in particular on transport related externalities tax interaction effects and redistribution effects working via the urban land market second we extend the model to a full spatial general equilibrium model and employ simulations to calculate sign and size of the optimal tax subsidy rate this model is calibrated to a typical german metropolitan area the results show that electric vehicles should not be subsidized but taxed the results are robust with respect to changes in the willingness to adopt electric vehicles the costs of driving electric vehicles and even if emissions of electric vehicles are zero

economic analysis of the contribution of photovoltaics to the decarbonization of the power sector abstract an analytical method has been developed for the calculation of the future 2013 2050 reduction of co2 emissions by the deployment of photovoltaic pv systems according to three scenarios from the international energy agency 2ds roadmap and new policies next we have also evaluated the financial extra costs incurred in the implementation of the pv systems which would replace the current traditional power generation systems taking as reference four geographical areas european union united states china and the world s average the established method also allows the comparison of the influence on the extra costs of the actual electricity mix as well as the current electricity prices corresponding to the above regional areas in these calculations we have taken into account several frequently ignored factors like solar cell degradation emissions attributed to the pv systems life cycle and the repowering due to the substitution of the systems after their life time is reached finally the results of this work can be of interest in energy planning policies related to the contribution of pv technologies for the decarbonization of the power generation system

a regional dynamic general equilibrium model of alternative climate change strategies outcomes and noncooperative equilibria this study finds that cooperative policies show much higher levels of emissions reductions than do noncooperative strategies that there are substantial differences in the levels of controls in both the cooperative and the noncooperative policies among different countries and that high income countries may be the major losers from cooperation jel h41 q4 q2 q20

unraveling the photovoltaic technology learning curve by incorporation of input price changes and scale effects in a large number of energy models the use of learning curves for estimating technological improvements has become popular this is based on the assumption that technological development can be monitored by following cost development as a function of market size however recent data show that in some stages of photovoltaic technology pv production the market price of pv modules stabilizes even though the cumulative capacity increases this implies that no technological improvement takes place in these periods the cost predicted by the learning curve in the pv study is lower than the market one we propose that this bias results from ignoring the effects of input prices and scale effects and that incorporating the input prices and scale effects into the learning curve theory is an important issue in making cost predictions more reliable in this paper a methodology is described to incorporate the scale and input prices effect as the additional variables into the one factor learning curve which leads to the definition of the multi factor learning curve this multi factor learning curve is not only derived from economic theories but also supported by an empirical study the results clearly show that input prices and scale effects are to be included and that although market prices are stabilizing learning is still taking place

reducing dependence on oil how policy entrepreneurs utilize the national security agenda to recruit government support the case of electric transportation in israel policy entrepreneurs are individuals who exploit an opportunity in order to influence political results for their own benefit we use the policy entrepreneurship literature as a theoretical lens for understanding how local players in the policy arena can use a national security agenda in order to promote an energy policy they desire using a case study approach we explain how an israeli electric vehicle company better place identified israel s acute national security priority to cut its dependence on oil and leveraged it along with environmental arguments to make the case for their approach to transportation our analysis also demonstrates how policy entrepreneurs collaborate with israeli bureaucrats senior politicians and lobbying groups to create a national shift toward electric cars

intergenerational resource rights efficiency and social optimality the discipline of economics is generally defined as the science of the allocation of scarce resources between competing social objectives given an initial distribution of resources between economic agents how would they behave so as to improve their welfare according to the pareto criterion the agents would exchange commodities until the opportunities for fruitful exchange were fully exhausted and no agent could be made better off without rendering at least one other agent worse off pareto efficiency is a powerful concept in microeconomic analysis provided that the initial distribution of property rights is equitable allocative efficiency gives rise to the best of all possible worlds acknowledging that the assumptions of perfect competition are often violated firms are monopolistic information is incomplete and externalities exist economists have argued for the modification of institutions so that economic reality will conform more closely to the assumptions of the model that yields such gratifying results but microeconomic theory has always maintained that allocative efficiency is in itself insufficient to maximize social welfare bator 1957 a social welfare function is required to discriminate a social optimum among the array of efficient allocations that correspond to alternative assignments of property rights though economists have posited alternative functional forms for the sake of pursuing conceptual arguments welfare functions have remained elusive constructs for well known theoretical and practical reasons consequently a sharp line of demarcation has been drawn between questions of efficiency the province of economics and equity the principal focus of ethical and political discourse in resource economics however the line demarcating efficiency and equity is often crossed the term optimal depletion appears regularly where only efficient depletion is meant while political debates about resource exploitation over time are laden with questions of the proper distribution of our natural patrimony between generations resource economists have predominantly espoused particular use rules that guarantee efficiency but overlook potential improvements in social welfare achievable through the reassignment of property rights across generations we document the evolution and current status of the misuse of the term optimal depletion in section ii we develop a simple two generation three period general equilibrium model in section iii to illustrate how alternative distributions of resource rights between generations relate to alternative pareto efficient solutions in section iv we demonstrate how different social welfare functions affect the optimal solution and associated assignment of resource rights between generations

dynamics of energy technologies and global change technological choices largely determine the long term characteristics of industrial society including impacts on the natural environment however the treatment of technology in existing models that are used to project economic and environmental futures remains highly stylized based on work over two decades at iiasa we present a useful typology for technology analysis and discuss methods that can be used to analyze the impact of technological changes on the global environment especially global warming our focus is energy technologies the main source of many atmospheric environmental problems we show that much improved treatment of technology is possible with a combination of historical analysis and new modeling techniques in the historical record we identify characteristic l such network e ects yield high barriers to entry even for superior competitors these simple observations allow three improvements to modeling of technological change and its consequences for global environmental change one is that the replacement of long lived infrastructures over time has also replaced the fuels that power the economy to yield progressively more energy per unit of carbon pollution from coal to oil to gas such replacement has d they also include endogenous generation of s we show that doing so can yield projections with lessened environmental impacts without necessarily incurring negative e ect on the economy arriving on that path by the year 2100 depends on intervening actions such as incentives to promote greater diversity in technology and lower barriers to entry for new infrastructures that could accelerate historical trends of decarbonization 1999 elsevier science ltd all rights reserved

business models for media firms does competition matter for how they raise revenue the purpose of this article is to analyze how competitive forces may influence the way media firms like tv channels raise revenue a media firm can either be financed by advertising revenue by direct payment from the viewers or the readers if we consider newspapers or by both we show that the scope for raising revenues from consumer payment is constrained by other media firms offering close substitutes this implies that the less differentiated the media firms content the larger is the fraction of their revenue coming from advertising a media firm s scope for raising revenues from ads on the other hand is constrained by how many competitors it faces we should thus expect that direct payment from the media consumers becomes more important the larger the number of competing media products