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1.
This paper explores the implications for global average temperature change of a set of reference and mitigation scenarios in a probabilistic framework. First, we use published probability density functions for climate sensitivity to investigate the likelihood of achieving targets expressed as levels or rates of global average temperature change. We find, for example, that limiting warming to 3 C above pre-industrial levels with at least a medium likelihood requires cumulative emissions reductions on the order of 30-60% below one unmitigated reference scenario by 2100, while a more favorable baseline scenario requires no reductions at all to achieve this outcome with the same likelihood. We further conclude that the rate of temperature change may prove to be more difficult to control, especially if most of the mitigation effort is postponed until later in the century. Rate of change targets of 0.1–0.2 °C/decade are unlikely to be achieved by a target for the long-term level of climate change alone. Second, we quantify relationships between mitigation costs and the likelihood of achieving various targets and show how this depends strongly on the reference scenario. Third, we explore relationships between medium-term achievements and long-term climate change outcomes. Our results suggest that atmospheric concentrations and the share of zero-carbon energy in the middle of the 21st century are key indicators of the likelihood of meeting long-term climate change goals cost-effectively. They also suggest that interim targets could be an effective means of keeping long-term target options open. Our analysis shows that least-cost mitigation strategies for reaching low climate change targets include a wide portfolio of reduction measures. In particular, fundamental long-term structural changes in the energy system in these scenarios are a necessary but not sufficient condition to achieve high likelihoods for low temperature targets. The cost-effective portfolio of emissions reductions must also address demand-side measures and include mitigation options in the industry, agriculture, and the forest sector.  相似文献   

2.
Transitioning towards a sustainable energy system requires the large-scale introduction of novel energy demand and supply technologies. Such novel technologies are often expensive at the point of their market introduction but eventually become cheaper due to technological learning. In order to quantify potentials for price and cost decline, the experience curve approach has been extensively applied to renewable and non-renewable energy supply technologies. However, its application to energy demand technologies is far less frequent. Here, we provide the first comprehensive review of experience curve analyses for energy demand technologies. We find a widespread trend towards declining prices and costs at an average learning rate of 18 ± 9%. This finding is consistent with the results for energy supply technologies and for manufacturing in general. Learning rates for individual energy demand technologies are symmetrically distributed around the arithmetic mean of the data sample. Absolute variation of learning rates within individual technology clusters of 7 ± 4%-points and between technology clusters of 7 ± 5%-points both contribute to the overall variability of learning rates. Our results show that technological learning is as important for energy demand technologies as it is for energy supply technologies. Applying the experience curve approach to forecast technology costs involves, however, unresolved uncertainties, as we demonstrate in a case study for the micro-cogeneration technology.  相似文献   

3.
A small macroeconomic model is constructed starting from a German money demand relation for M3 based on quarterly, seasonally unadjusted data for the period from 1976 to 1996. In contrast to previous studies we build a vector error correction model for M3, GNP, an inflation rate and an interest rate spread variable to represent opportunity costs of holding money. Furthermore, import price inflation is added as an exogenous variable. The model is used to analyze the relation between money growth and inflation by means of an impulse response analysis.We thank Gerd Hansen for soliciting two anonymous referee reports on an earlier version of this article and thereby helping in the editorial process for this volume. We are grateful to him, Timo Teräsvirta, Kirstin Hubrich and the two referees for comments that helped us to improve our paper. Financial support was provided by the DFG, Sonderforschungsbereich 373.  相似文献   

4.
Recent national technology foresight studies as well as the Millennium Project of the American Council for the United Nations University are very much based on “nodes of discussion.” These short statements are called, e.g., topics, issues, or developments. This article provides a framework for the classification and analysis of nodes related to future technological development. Key concepts of the article are “technological generalization” and “leitbild.” The topics in the technology foresight Delphi studies can be seen as different kinds of generalizations from already realized technological developments. Leitbild is a German word. Its most general meaning is a guiding image. Like a common vision, a leitbild creates a shared overall goal, offers orientation toward one long-term overall goal, and provides a basis for different professions and disciplines to work in the same direction. The analysis of leitbilder and emerging technological paradigms might contribute to the construction of topics and issues and to the argumentation processes related to them.  相似文献   

5.
The results of a Delphi study on the future of the Indian tea industry are presented. Most of the information obtained for the study helps in formulating and validating a system dynamics model. The model also considers the occurrence of new events as visualized by the panelists. It is shown, however, that the policies recommended by the panelists yield poor industry behavior when Delphi-predicted new events operate in the environment. This may be due to lack of comprehension of the complexity of interaction between policies proposed and new events visualized by the panelists. On the basis of this investigation, it is proposed that Delphi and system dynamics studies should complement each other in arriving at viable policy decisions.  相似文献   

6.
In order to assess the importance of monetary and financial developments for key macroeconomic variables in the euro area a money demand system for M3 is estimated adopting a structural cointegrating VAR approach. While maintaining a good statistical representation of the data, long-run relationships are based on economic theory. By using generalized response profiles the dynamics of the money demand system is investigated without any further identifying assumptions. Error bounds of the profiles are derived using bootstrap simulations.  相似文献   

7.
This article applies cointegration techniques to estimate a monthly demand system for meat in Italy. In contrast to existing studies where Engle and Granger's two step procedure and Triangular Vector Error Correction Model (TVECM) representations are usually exploited, it applies a cointegrated Vector Error Correction Model (VECM) where also prices and expenditure enter endogenously the system and the cointegration rank is not assumed to be known a priori but subject to inference. It highlights some of the advantages of using the VECM compared to the TVECM, including the possibility of testing the cointegration rank of the system and the (weak and strong) exogeneity of prices and expenditure within a well-specified statistical model. This may lead to remarkable improvements in the efficiency of parameters system estimates.  相似文献   

8.
This paper examines how alcohol content affects the consumption of alcoholic beverages in Finland. Three different quality hypotheses are studied and compared: Fisher and Shell, Theil, and an additive one. The comparison of the hypotheses is based on quality elasticities implied by the hypotheses. The results show that, under all hypotheses, alcohol content positively affects the demand for alcoholic beverages, and this effect depends negatively on income. The results of the comparison of the hypotheses show that the additive fits the data best. However, the other hypotheses are almost as good: Fisher and Shell's hypothesis better than Theil's.I would like to thank K. Koskela, A. Nyberg, M. Salo, M. Stenius, and I. Suoniemi for their useful comments and suggestions. The author bears sole responsibility for any remaining errors.  相似文献   

9.
This paper estimates the household demand for energy and fuels. The linear expenditure model is estimated using data from eight OECD countries over a period of sixteen years. The basic similarities in household demand for fuels and the differences among OECD countries are discussed. The results indicate that household demand for energy is highly income dependent. With regard to four basic fuels, the income and price elasticities for gasoline and gas are higher than for either coal or oil. The demand patterns are shown to differ significantly among groups of OECD countries. Coal has been gradually replaced by oil as the major household fuel in OECD countries, whereas the demand pattern for gas has changed only a little during the fifties and sixties.  相似文献   

10.
The paper introduces Bayesian inference into a demand model. This allows us to test for the negativity condition of the substitution matrix which is difficult to handle directly in the traditional approach. To illustrate the Bayesian inference procedures, we estimate the Rotterdam model and test the demand properties using Japanese data. The empirical results show the importance of specifically considering negativity in demand analysis. First version received: September 1997/final version received: February 1998  相似文献   

11.
The present study is an attempt to model the dynamic interactions between money, output and prices in a structural vector autoregression framework. The primary concern of the paper is to examine the sources of variations and response of one variable to changes in others in a system of economic variables in the Indian context. Using quarterly data from 1970Q1 to 1990Q4, we find that structural factors, in addition to monetary factors, play an important role in generating and sustaining the process of inflation and fluctuations in economic activity. An increase in money/credit supply is found to increase output and prices in the short-run and prices in the long-run, while a non-accommodating monetary policy is ineffective in controlling inflation even at the cost of substantial output losses, thereby indicating relative rigidities in price movements. Another interesting finding is that the monetary authority responds differently to different price shocks, exercising its leverage in altering the quantity as well as the composition of aggregate money supply. Our findings also indicate that the economy is characterized by relatively large and infrequent shocks to ‘price/cost’-related factors. Finally, our analysis suggests that a simple monetary targeting without adequate ‘supply side’ measures may not be able to serve the objective of maintaining growth with price stability.  相似文献   

12.
To improve our understanding of processes involved in the formation and growth of new technological systems in the energy sector and to identify the associated key challenges for policy makers managing the transformation process, we examine the development of the German technological system for solar cells over the past 25 years. We use a "technological system' approach in which we will trace the evolution of actors, networks and institutions that have a bearing on the generation and diffusion of solar cells. An initial preparatory stage lasted until about 1989 and was mainly characterized by knowledge build-up induced by a Federal RDD programme. This was followed by a second stage characterized by political struggle over the regulatory framework and a subsequent beginning of a virtuous circle for solar cells. In the concluding discussion, we emphasize four key features of the evolution of the technological system: (1) the role of a coalition of system builders that successfully influenced the regulatory framework so that markets could be formed: (2) the considerable length of the learning period and the large number of actors that need to learn; (3) the importance of policies that form early markets (not only early niche markets, but beyond those) as only markets may induce firms to enter and learn, and (4) the need to run market formation policies simultaneous to policies that maintain technological variety.  相似文献   

13.
A censored system of household fat and oil demand equations is estimated with a two-step procedure, using cross-sectional data from the 1987–1988 US Nationwide Food Consumption Survey. Own price and total expenditure elasticities are close to unity and there is no evidence of gross substitutability. Compensated elasticities suggest net substitution among the products considered.  相似文献   

14.
A new demand system, called a globally flexible, quadratic almost ideal demand system (GF–QUAIDS), integrates both the quadratic Engel curve and the Fourier series. This novel GF–QUAIDS model is applied to study the demand for meats and fish in Taiwan. Empirical results show that the GF–QUAIDS fits the data well and that, by using the likelihood ratio test, its nested models are rejected, including the locally flexible functional form and the linear Engel curve. Nevertheless, other empirical model-selection measures indicate that the GF–QUAIDS can be as good as its famous nested models such as the AIDS, QUAIDS and GF–AIDS.  相似文献   

15.
In a system with n input factors there are n − 1 independent cost shares. An often-used approach in estimating factor demand systems is to (implicitly or explicitly) assume that there is a (independent) cointegrating relationship for each of the n − 1 independent cost shares. However, due to technological changes, there might not be as many cointegrating relationships as there are (independent) cost shares. This article presents a flexible demand system that allows for both factor neutral technological changes as well as technological changes that affect the relative use of the different factors. The empirical tests indicate that there are fewer cointegrating relationships than usually implied using conventional estimation approaches. This result is consistent with technological changes that affect the relative use of the different input factors. I argue that, since such unexplained technological changes are likely to affect input factor decisions, a demand system that allows for such changes should be preferred.  相似文献   

16.
Franz Wirl  Gerd Infanger 《Empirica》1985,12(2):227-245
Zusammenfassung Die meisten empirischen Untersuchungen über das Ausmaß der jüngsten Energieeinsparungen verwendeten ökonometrische Beziehungen und Elastizitäten. Diese Arbeit jedoch geht von einer technischen Beschreibung des Services thermische Behaglichkeit aus. Basierend auf empirischem Datenmaterial über die Infrastruktur und das Klima der Stadt Wien werden sowohl die Aussichten und das Potential an Energieeinsparungen quantifiziert als auch der Effekt spezifischer Politiken. Für diesen Zweck wurde ein nichtlineares Optimierungsmodell mit disjunktiven Randbedingungen entwickelt und gelöst.

Research leading to this paper was supported by a grant from the Austria Federal Ministry of Science and Research, and that support is gretefully acknowledged. We wish to thank P. J. Jansen for discussions on this topic and also the referees for their valuable comments on this paper.  相似文献   

17.
18.
In this paper, we set up a switching regression model in which individual coefficients are allowed to shift at different change-points. We also apply it to the energy demand equations and examine structural change in the demands for total fuel oil and for light oil and kerosene at the second oil crisis. It is shown that assuming the different change-points for individual coefficients yields more Plausible results than assuming the same change-point for all coefficients.We thank Professor S. Katayama for his help in another related project.  相似文献   

19.
As a result of more and more serious energy risks, the study of national energy security zoning is not only the basic requirement of energy risk management but also the new demand of economic development for the energy industry. Firstly, this paper analyzes the basic situation of energy resources and production and consumption of primary. energy from 1996 to 2005 in China. Secondly; this paper founds an Energy Security Index System formed by six indices including the percentage of energy reserves, interlocal dependent degree, energy elasticity coefficient and so on. It subsequently calculates the weight of these indices with the factor analysis rating method Lastly, the paper evaluates and zones the abilities of energy security of 30 provinces in China with the grey chuster method According to their security; the 30 provinces are classified into three different levels: high, medium, and low levels. The regions at low energy security level include Beijing, Shanghai, Zhejiang, Fujian, Guangdong, Guangxi and Hainan. They are mainly littoral and short of primary energy production while mostly dependent on other provinces. Those at medium energy security level include 15 provinces (cities or districts), such as Liaoning, Tianjin, Hebei, Shandong, Henan, Hunan and so on. These provinces are in the northeast, north, east of and central China. Those at high energy security level contain Shanxi. lnner Mongolia, Heilongjiang, Jilin, Chongqing, Sichuan, Shaanxi. Xinjiang. These provinces are the main primary energy production bases.  相似文献   

20.
<正> 和任何商品一样,股票的价格围绕价值的波动幅度与方向仍然要取决于股市上的供给〔股票、债券等证券品种)与需求(需要购买相关证券品种的资金量)的相互关系。中国股市的成长过程也是一个供给和需求双向扩容的过程影响股市供给与需求的因素有:股市规模的扩张速度(资产证券化率的增长速度)、消除股权结构泡沫(部分国有股、法人股的流通)、新股的发行规模等。  相似文献   

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