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on Environmental Economics |
| By: | Barbara Praetorius; Katja Schumacher |
| Abstract: | In a carbon constrained world, at least four classes of greenhouse gas mitigation options are available: Energy efficiency, fuel switching, introduction of carbon dioxide capture and storage along with renewable generating technologies, and reductions in emissions of non-CO2 greenhouse gases. The role of energy technologies is considered crucial in climate change mitigation. In particular, carbon capture and storage (CCS) promises to allow for low-emissions fossil-fuel based power generation. The technology is under development; a number of technological, economic, environmental and safety issues remain to be solved. With regard to its sustainability impact, CCS raises a number of questions: On the one hand, CCS may prolong the prevailing coal-to-electricity regime and countervail efforts in other mitigation categories. On the other hand, given the indisputable need to continue using fossil fuels for some time, it may serve as a bridging technology towards a sustainable energy future. In this paper, we discuss the relevant issues for the case of Germany. We provide a survey of the current state of the art of CCS and activities, and perform an energy-environment-economic analysis using a general equilibrium model for Germany. The model analyzes the impact of introducing carbon constraints with respect to the deployment of CCS, to the resulting greenhouse gas emissions, to the energy and technology mix and with respect to interaction of different mitigation efforts. The results show the relative importance of the components in mitigating greenhouse gas emissions in Germany. For example, under the assumption of a CO2 policy, both energy efficiency and CCS will contribute to climate gas mitigation. A given climate target can be achieved at lower marginal costs when the option of CCS is included. We conclude that, given an appropriate legal and policy framework, CCS, energy efficiency and some other mitigation efforts are complementary measures and should form part of a broad mix of measures required for a successful CO2 mitigation strategy. |
| Date: | 2008 |
| URL: | http://d.repec.org/n?u=RePEc:diw:diwwpp:dp820&r=env |
| By: | Tol, Richard S. J. (Economic and Social Research Institute (ESRI)) |
| Abstract: | I review the literature on the economic impacts of climate change, an externality that is unprecedentedly large, complex, and uncertain. Only 14 estimates of the total damage cost of climate change have been published, a research effort that is in sharp contrast to the urgency of the public debate and the proposed expenditure on greenhouse gas emission reduction. These estimates show that climate change initially improves economic welfare. However, these benefits are sunk. Impacts would be predominantly negative later in the century. Global average impacts would be comparable to the welfare loss of a few percent of income, but substantially higher in poor countries. There are over 200 estimates of the marginal damage cost of carbon dioxide emissions. The uncertainty about the social cost of carbon is large and right-skewed. For a standard discount rate, the expected value $50/tC, which is much lower than the price of carbon in the European Union but much higher than the price of carbon elsewhere. Current estimates of the damage costs of climate change are incomplete, with positive and negative biases. Most important among the missing impacts are the indirect effects of climate change on economic development, large scale biodiversity loss, low probability – high impact scenarios, the impact of climate change on violent conflict, and the impacts of climate change beyond 2100. From a welfare perspective, the impact of climate change is problematic because population is endogenous, and because policy analyses should separate impatience, risk aversion, and inequity aversion between and within countries. |
| Keywords: | Impacts of climate change; social cost of carbon |
| JEL: | Q54 |
| Date: | 2008–09 |
| URL: | http://d.repec.org/n?u=RePEc:esr:wpaper:wp255&r=env |
| By: | Tol, Richard S. J. (Economic and Social Research Institute (ESRI)) |
| Abstract: | The current EU proposal on greenhouse gas emission reduction has 28 targets for 2020: an EU-wide one for carbon dioxide emissions covered by the European Trading System, and one target for non-ETS emission per Member State. Implementation is necessarily more expensive than needed. I consider three alternative proposals to reduce costs. In the Irish proposal, Member States can purchase ETS permits to offset excess non-ETS emissions. In the Polish proposal, Member States can sell excess non-ETS emissions in the ETS. In the Swedish proposal, Member States can trade their non-ETS allocations. I compare these three alternatives to the default policy (no flexibility outside the ETS) and to the cost-effective solution (full flexibility). I calibrate a simple model to the results of the impact assessment of the European Commission. This reveals that European Commission did not fully disclose all details, and that odd assumptions were made. In the case of three Member States, the non-ETS allocation exceeds the projected emissions. The results show that the alternative flexibility mechanisms would be used to only a limited extent, but would help to suppress the costs of meeting the target. The Swedish and Polish proposals come closest to the cost-effective solution as full use is made of the hot air in the non-ETS system. The Irish proposal performs best if there are negative surprises in either the cost of non-ETS emission reduction or non-ETS emission projections. |
| Keywords: | Climate change; Emissions trade; European Union |
| JEL: | Q54 |
| Date: | 2008–09 |
| URL: | http://d.repec.org/n?u=RePEc:esr:wpaper:wp256&r=env |
| By: | Kurukulasuriya, Pradeep; Mendelsohn, Robert |
| Abstract: | The study develops a new method to measure the impacts of climate change on agriculture called the Agro-Ecological Zone (AEZ) Model. A multinomial logit is estimated to predict the probability of each AEZ in each district. The average percentage of cropland and average crop net revenue are calculated for each AEZ. Then an estimate of the amount of cropland in Africa and where it is located is provided. Using current conditions, the model calculates baseline values of cropland and crop net revenue, and estimates the future impact of climate change using two scenarios-harsh and mild. Total cropland does not change much across the two climate scenarios. However, the predicted change in African crop revenue ranges from a loss of 14 percent in the mild climate scenario to 30 percent in the harsher climate scenario. The analysis reveals that the greatest harm from climate change is that it will shift farms from high to low productive AEZs. The approach not only identifies the aggregate impacts, but also indicates where the impacts occur across Africa. The central region of Africa is hurt the most, especially in the harsher climate scenario. The Agro-Ecological Zone Model is a promising new method for valuing the long-term impacts of climate change on agriculture. |
| Keywords: | Climate Change,Common Property Resource Development,Forestry,Crops&Crop Management Systems,Global Environment Facility |
| Date: | 2008–09–01 |
| URL: | http://d.repec.org/n?u=RePEc:wbk:wbrwps:4717&r=env |
| By: | Patrice Dumas (LMD - Laboratoire de Météorologie Dynamique - CNRS : UMR8539 - INSU - Université Pierre et Marie Curie - Paris VI - Polytechnique - X - Ecole Normale Supérieure de Paris, CIRED - Centre international de recherche sur l'environnement et le développement - CIRAD : UMR56 - CNRS : UMR8568 - Ecole des Hautes Etudes en Sciences Sociales - Ecole Nationale des Ponts et Chaussées - Ecole Nationale du Génie Rural des Eaux et des Forêts); Minh Ha-Duong (CIRED - Centre international de recherche sur l'environnement et le développement - CIRAD : UMR56 - CNRS : UMR8568 - Ecole des Hautes Etudes en Sciences Sociales - Ecole Nationale des Ponts et Chaussées - Ecole Nationale du Génie Rural des Eaux et des Forêts) |
| Abstract: | Many economic sectors, like housing or transportation, are exposed to climate and likely to suffer efficiency losses when climate changes. The global economy is far from dematerialized yet, these sectors represent a significant fraction of the existing capital stock. Using an optimal growth model with perfect knowledge, we examine the balance between these efficiency losses and investment in adaptation measures, which can become sunk costs when climate changes even more. Simulations remind that adaptation should be proactive rather than reactive: protection measures installed today are not designed for today's climate only, but anticipate future warmer conditions over their lifetime. While there is an over-investment compared with a no climate change baseline, the overall cost to adapt is relatively low in front of the potential losses from misadaptation. This allows to stay almost always well adapted to climate. |
| Keywords: | Climate change; adaptation; optimal growth; integrated assessment model |
| Date: | 2008–02–01 |
| URL: | http://d.repec.org/n?u=RePEc:hal:wpaper:halshs-00207621_v2&r=env |
| By: | Geethanjali Selvaretnam; Kannika Thampanishvong |
| Abstract: | The Clean Development Mechanism (CDM) gives the industrialized countries (the Annex I countries) some flexibility in achieving their emission reduction targets under the Kyoto Protocol by allowing them to pay for projects that reduce greenhousegas emissions in the developing countries (the non-Annex I countries). This paper is devoted to evaluate the efficacy of the CDM. We show that, on one hand, the emissions in the non-Annex I country decline because of abatement undertaken by the Annex I country under the CDM; on the other hand, the total emissions may increase because (i) the Annex I country will increase emissions in its own country, and (ii) the non-Annex I country, under some conditions, could crowd out the benefits from the CDM projects by increasing its domestic emissions. In order for the CDM to be more effective, we recommend that only partial credits should be given to the Annex I country that undertakes abatement under the CDM. We also suggest that the authority overseeing the CDM should not allow the CDM projects to be hosted by the non-Annex I country that is more conscious about the environment. |
| Keywords: | Clean Development Mechanism (CDM), Kyoto Protocol, emission, abatement. |
| JEL: | D24 Q51 Q54 |
| Date: | 2008–08 |
| URL: | http://d.repec.org/n?u=RePEc:san:wpecon:0808&r=env |
| By: | Arief Anshory Yusuf (Department of Economics, Padjadjaran University) |
| Abstract: | INDONESIA-E3 is a CGE (Computable General Equilibrium) model built to analyze the Economy, Equity,and the Environment - the three inter-related aspects of sustainable development. It is a multi-sectors, multi-households CGE model that incorporate carbon emissions and taxation and with a strong feature in distributional analysis. It can be used, for example, to study the impact of environmental reforms, such as carbon emission reduction and energy pricing policy, has on inequality and poverty for the case of Indonesia. The model captures the inter-dependence among markets in the determination of both price of commodities and factor of productions and how it will affect distribution of income. As a departure from the previous literature, the disaggregation of household by expenditure classes allows for precise estimates of the distributional impact and poverty incidence. This paper describes the model structure such as production and consumption structure, database, parameters, method for distributional analysis, possible closures, and and method for sensitivity analysis. |
| Keywords: | INDONESIA-E3, Computable General Equilibrium, Equity, Environment |
| JEL: | C68 D58 |
| Date: | 2008–09 |
| URL: | http://d.repec.org/n?u=RePEc:unp:wpaper:200804&r=env |
| By: | Montero, José María; Larraz, Beatriz; Chasco, Coro |
| Abstract: | The elaboration of Environmental Quality Indexes (EQI) for big cities is one of the main topics in regional and environmental economics. One of the usual methodological paths consists of generating a single measure as a linear combination of several air contaminants applying Principal Component Analysis (PCA). Then, as a final step, a spatial interpolation is carried out to determine the level of contamination across the city in order to point out the so-called ‘hot points’. In this article, we propose an alternative approach to build an EQI introducing some methodological and practical novelties. From the point of view of the selection of the variables, first we will consider noise -joint to air pollution- as a relevant environmental variable. We also propose to add ‘subjective’ data -available at the census tracts level- to the group of ‘objective’ environmental variables, which are only available at a number of environmental monitoring stations. This combination leads to a mixed environmental index (MEQI), which is more complete and adequate in a socioeconomic context. From the point of view of the computation process, we use kriging to match the monitoring stations registers to the Census data. We follow an inverse process as usual, since it leads to better estimates. In a first step, we krige the environmental variables to the complete surface and finally, we elaborate the environmental index. At last, in order to build the final synthetic index, we do not use Principal Components Analysis -as it is usual in this kind of exercises- but a better one, the Pena Distance method (DP2). |
| Keywords: | Environmental index; Air pollution; Noise; Subjecive expectations; Kriging; Distance indicators |
| JEL: | C43 Q53 C21 |
| Date: | 2008–09–24 |
| URL: | http://d.repec.org/n?u=RePEc:pra:mprapa:10736&r=env |
| By: | Gerardo Marletto |
| Abstract: | Orthodox economics sees transport as a market which can be made more sustainable by improving its self-regulating capacity. To date this static approach has not been able to limit the growing demand for transport and its increasing environmental impact. Better results might be obtained by using evolutionary and institutional economics. Starting from these theories, a sustainable transport policy should be based on three fundamental considerations. First, transport is not a market, but a sum of systems affected by path-dependence and lock-in phenomena. Second, transport is not sustainable because it is locked in environmentally sub-optimal systems. Third, structural changes in technologies and organisations, institutions, and values are needed to establish more sustainable transport systems. We give an example of the use of an institutional/evolutionary approach to sustainable transport policies in the transition from the system of mass motorisation to the new urban mobility system. |
| Keywords: | Sustainable transportation; Transport policy; Environmental economics; Institutional economics; Evolutionary economics |
| JEL: | B52 Q58 R40 |
| Date: | 2008 |
| URL: | http://d.repec.org/n?u=RePEc:cns:cnscwp:200814&r=env |
| By: | Marcus Wagner; Patrick Llerena |
| Date: | 2008 |
| URL: | http://d.repec.org/n?u=RePEc:ulp:sbbeta:2008-22&r=env |
| By: | Karen Pittel (CER-ETH - Center of Economic Research at ETH Zurich, Switzerland); Lucas Bretschger (CER-ETH - Center of Economic Research at ETH Zurich, Switzerland) |
| Abstract: | We analyze an economy in which sectors are heterogeneous with respect to the intensity of natural resource use. Long-term dynamics are driven by resource prices, sectoral composition, and directed technical change. We study the balanced growth path and determine stability conditions. Technical change is found to be biased towards the resource-intensive sector. Resource taxes have no impact on dynamics except when the tax rate varies over time. Constant research subsidies raise the growth rate while increasing subsidies have the opposite effect. We also find that supporting sectors by providing them with productivity enhancing public goods can raise the growth rate of the economy and additionally provide an effective tool for structural policy. |
| Keywords: | sustainable development, sectoral heterogeneity, directed technical change |
| JEL: | O4 O41 Q01 Q3 |
| Date: | 2008–09 |
| URL: | http://d.repec.org/n?u=RePEc:eth:wpswif:08-96&r=env |
| By: | Yulia Marchenko (StataCorp) |
| Abstract: | In the past decade, many statistical methods have been proposed for the analysis of case–control genetic data with an emphasis on haplotype-based disease association studies. Most of the methodology has concentrated on the estimation of genetic (haplotype) main effects. Most methods accounted for environmental and gene-environment interaction effects by utilizing prospective-type analyses that may lead to biased estimates when used with case–control data. Several recent publications addressed the issue of retrospective sampling in the analysis of case–control genetic data in the presence of environmental factors by developing new efficient semiparametric statistical methods. I present the new Stata command, haplologit, that implements efficient profile-likelihood semiparametric methods for fitting gene–environment models in the very important special cases of a) a rare disease, b) a single candidate gene in Hardy-Weinberg equilibrium, and c) independence of genetic and environmental factors. |
| Date: | 2008–09–11 |
| URL: | http://d.repec.org/n?u=RePEc:boc:usug08:08&r=env |
| By: | Aslan, Alper |
| Abstract: | Son zamanlarda, küresel ısınma ve küresel ısınmanın iklim değişikliği üzerindeki potansiyel etkisi üzerine kamunun ilgisi açık bir şekilde artmaktadır. Buna bir tepki olarak, hükümetler küresel ısınmayı hafifletme için uluslararası iklim değişikliği stratejileri planlamaya girişmektedirler. Ampirik çalışmalar sera sıcaklığının ana nedeni olarak karbon dioksit (CO2) emisyonu olduğunu göstermektedir. CO2 emisyonunun kalıcılığının ve stokastik dinamiklerinin incelenmesi ve analiz edilmesi, politika yapıcıları için karbon dioksit emisyonunun çevreye olan etkilerinin hesaplanmasında çok önem arz etmektedir. Bu çalışmada, Afrika, Merkezi ve Güney Amerika, Merkezi Asya, Merkezi Avrupa, Uzak Doğu, Orta Doğu, Kuzey Amerika, Okyanusya ve Batı Avrupa ülkeleri arasında kişi başına karbon dioksit emisyon kalıcılığı ve yakınsaması 1950-2004 dönemi için Lima ve Resende (2007) kalıcılık yöntemi uygulanarak incelenmiştir. IPS (Im, Peseran ve Shin) test sonuçları karbon dioksit emisyonu için birim kökün yokluk hipotezi reddedilememiştir. Bu nedenle sonuçlar ele alınan ülke grupları itibariyle CO2 emisyonu güçlü bir şekilde kalıcılık sergilediğini göstermektedir. |
| Keywords: | CO2 emisyonu; Yakınsama; Kalıcılık; Birim Kök. |
| JEL: | Q50 C23 Q53 |
| Date: | 2008 |
| URL: | http://d.repec.org/n?u=RePEc:pra:mprapa:10591&r=env |
| By: | Bernhard G. Gunter (Bangladesh Development Research Center (BDRC)); Atiq Rahman (Bangladesh Centre for Advanced Studies (BCAS)); A. F. M. Ataur Rahman (Department of Economics, North South University, Dhaka) |
| Abstract: | This paper compares the vulnerabilities to climate change and climate variability of the indigenous people with the Bengali population of Bangladesh. It distinguishes between (a) individual vulnerabilities that are related to an individual’s capability to adapt to climate change and; (b) spatial vulnerabilities, that is, vulnerabilities that are related to the location of a person (like the exposure to climate change-induced disasters). While an individual’s capability to adapt to climate change is determined by many factors, some relatively simple approximation is to look at poverty, landlessness, and illiteracy. Spatial vulnerabilities are reviewed by looking at drought hazard maps, flood hazard maps, landslide hazard maps, and cyclone hazard maps. Hence, the paper compares levels of poverty, landlessness, illiteracy, and the more direct though also more subjective exposures to increased droughts, floods, landslides, and cyclones across the two population groups. The paper concludes with some broad suggestions on adaptation strategies of indigenous people as well as suggestions for policy interventions to reduce climate change-induced vulnerabilities for indigenous people in the Chittagong Hill Tracts (CHT). |
| Keywords: | Bangladesh, climate change, vulnerability |
| Date: | 2008–04 |
| URL: | http://d.repec.org/n?u=RePEc:bnr:wpaper:1&r=env |
| By: | T.T. Ha Pham (G2ELAB - Grenoble Electrical Engineering - Institut National Polytechnique de Grenoble - INPG - Université Joseph Fourier - Grenoble I); Cédric Clastres (G2ELAB - Grenoble Electrical Engineering - Institut National Polytechnique de Grenoble - INPG - Université Joseph Fourier - Grenoble I, LEPII - Laboratoire d'Économie de la Production et de l'Intégration Internationale - CNRS : UMR5252 - Université Pierre Mendès-France - Grenoble II); F. Wurtz (G2ELAB - Grenoble Electrical Engineering - Institut National Polytechnique de Grenoble - INPG - Université Joseph Fourier - Grenoble I); S. Bacha (G2ELAB - Grenoble Electrical Engineering - Institut National Polytechnique de Grenoble - INPG - Université Joseph Fourier - Grenoble I); E. Zamaï (G-SCOP - Laboratoire des sciences pour la conception, l'optimisation et la production - CNRS : UMR - Institut National Polytechnique de Grenoble - INPG - Université Joseph Fourier - Grenoble I) |
| Abstract: | The study presented in this paper takes part in a project aiming to increase the value of solar production for residential application with a medium-term vision where preferential solar energy subsidies will decrease before to disappear. This study is dedicated to propose and develop optimal energy architecture at supply side, a multi-source system based on photovoltaic (PV) solar energy connecting to main electrical network, taking further into account the effectiveness of intelligent demand side management. To investigate this issue, a method of optimal supplying system sizing and household energy management has been developed. This method, which has been formulated employing Mix Integer Linear Programming (MILP), enables the calculation of the appropriate configuration for power supply system and the optimal operation control to be applied. Using a Net Present Value (NPV) and Probability Index (P.I) basis, the economic analysis allows estimation of the viability of the proposed system under different factors of influence such as renewable energy policies, technology evolutions leading to cheaper installed PV module cost and deregulated electricity market. Simulation results show that, the solution makes it possible for PV power to be significantly valued by the customers without subsidized measures. |
| Keywords: | connected-grid PV system ; battery storage ; sizing optimization ; energy management ; MILP |
| Date: | 2008–07 |
| URL: | http://d.repec.org/n?u=RePEc:hal:journl:halshs-00323581_v1&r=env |
| By: | Jean-Philippe Atzenhoffer |
| Abstract: | The Tragedy of the Commons refers to the dissipation of a common- pool ressource when any appropriator has free access to it. Under the behavior of absolute payoff maximisation, the common-pool resource game leads to a Nash equilibrium in which the resource is overexploited. However, some empirical studies show that the overutilization is even larger than the Nash equilibrium predicts. We account for these results in an evolutionary framework. Under an imitation-experimentation dynamics, the long run stable behavior implies a larger exploitation of the resource than in the classical Nash equilibrium. |
| Keywords: | common-pool resource, imitation behavior, evolutionary stable strategy, evolutionary games. |
| JEL: | C73 D41 Q20 |
| Date: | 2008 |
| URL: | http://d.repec.org/n?u=RePEc:ulp:sbbeta:2008-21&r=env |
| By: | Khan, Haider A. |
| Abstract: | This paper analyses both global and regional approaches to solving problems of energy security and ecological imbalance by addressing specifically the problems of China?s energy security. China?s growing energy dependence has become a major concern for both economic and national security policymakers in that country. The ambitious goal of modernization of the economy along the lines of the other newly industrialized economies (NIEs) of Asia has succeeded only too well, and it is difficult to reorient economic priorities. If examined rigorously, such an economic strategic assumption can be seen to entail the goal of creating further technological capabilities. In particular, China seems to be firmly committed to the creation of a largely self-sustaining innovation system as part of a knowledge-based economy of the future. Such innovation systems, called positive feedback loop innovation systems or POLIS have been created by advanced countries, and NIEs such as South Korea and Taiwan are proceeding to create these as well. But this will add to its energy burden and further dependence on the US as the power which controls the key sea lanes. Only a strategic reorientation to building a self-sustaining POLIS and appropriate regional cooperation institutions can lead to the way out of the current dilemma for China. Fortunately, such a model of POLIS which is distributionally and ecologically sensitive can be built for China and applied strategically to lead towards a sustainable development trajectory. ... |
| Keywords: | China, development strategy, energy, environment, POLIS, innovation system, regional cooperation |
| Date: | 2008 |
| URL: | http://d.repec.org/n?u=RePEc:unu:wpaper:rp2008-56&r=env |
| By: | Heger, Martin; Julca, Alex; Paddison, Oliver |
| Abstract: | This paper analyses the impact of natural disasters in the Caribbean. The economic impact of natural disasters in the region has been significant, resulting in widespread destruction of the productive economy. This paper presents the main macroeconomic impact of disasters, e.g., a deteriorating fiscal balance, a collapse of growth and a worsening external balance, as a consequence of damage resulting from the event. By making special reference to the small-island developing state nature of many countries in the region, valuable lessons of the impact of such disasters on the capital stock can be learnt, particularly as the interruption of production of goods and services can be particularly devastating in an environment where few large sectors (agriculture, tourism) dominate the economic landscape. |
| Keywords: | natural disasters, Caribbean, diversification, trade, environment |
| Date: | 2008 |
| URL: | http://d.repec.org/n?u=RePEc:unu:wpaper:rp2008-25&r=env |
| By: | Oberndorfer, Ulrich |
| Abstract: | This paper constitutes – to our best knowledge – the first econometric analysis on stock market effects of the EU Emission Trading Scheme (EU ETS). Our results suggest that EU Emission Allowance (EUA) price developments matter to the stock performance of electricity firms: EUA price changes and stock returns of the most important European electricity corporations are shown to be positively related. This effect does not work asymmetrically, so that stock markets do not seem to react differently to EUA appreciations in comparison to depreciations. The carbon market effect is shown to be both time- and countryspecific: It is particularly strong for the period of EUA market shock in early 2006, and differs with respect to the countries where the electricity corporations analysed are headquartered. Stock market reactions to EUA volatility could not be shown. Dieses Papier untersucht die Aktienmarkteffekte von Preisentwicklungen auf dem Markt für Emissionszertifikate im Rahmen des Europäischen Emissionshandelssystems (EU ETS). Die Analyse fokussiert dabei auf die Aktienmarktperformance des europäischen Elektrizitätssektors, der gemessen an CO2-Emissionen größten Branche im EU ETS. Nach unseren Ergebnissen spielt der Zertifikatmarkt eine wichtige Rolle für die Aktienentwicklungen der analysierten Elektrizitätsfirmen. Ein Anstieg des Zertifikatpreises sorgt für Kursgewinne bei den Aktien der Elektrizitätsfirmen aus fast allen europäischen Ländern. Hingegen scheint die Volatilität der Emissionsrechte entgegen anderslautender Erwartungen nicht auf die Aktienkursentwicklung der untersuchten Unternehmen zu wirken. |
| Keywords: | EU ETS, electricity stocks, asset pricing |
| JEL: | C13 G12 Q43 Q48 |
| Date: | 2008 |
| URL: | http://d.repec.org/n?u=RePEc:zbw:zewdip:7382&r=env |