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1.
In this paper, we assess future water demands for the agricultural (irrigation and livestock), energy (electricity generation, primary energy production and processing), industrial (manufacturing and mining), and municipal sectors, by incorporating water demands into a technologically-detailed global integrated assessment model of energy, agriculture, and climate change — the Global Change Assessment Model (GCAM). Base-year water demands – both gross withdrawals and net consumptive use – are assigned to specific modeled activities in a way that maximizes consistency between bottom-up estimates of water demand intensities of specific technologies and practices, and top-down regional and sectoral estimates of water use. The energy, industrial, and municipal sectors are represented in fourteen geopolitical regions, with the agricultural sector further disaggregated into as many as eighteen agro-ecological zones (AEZs) within each region. We assess future water demands representing six socioeconomic scenarios, with no constraints imposed by future water supplies. The scenarios observe increases in global water withdrawals from 3710 km3 year 1 in 2005 to 6195–8690 km3 year 1 in 2050, and to 4869–12,693 km3 year 1 in 2095. Comparing the projected total regional water withdrawals to the historical supply of renewable freshwater, the Middle East exhibits the highest levels of water scarcity throughout the century, followed by India; water scarcity increases over time in both of these regions. In contrast, water scarcity improves in some regions with large base-year electric sector withdrawals, such as the USA and Canada, due to capital stock turnover and the almost complete phase-out of once-through flow cooling systems. The scenarios indicate that: 1) water is likely a limiting factor in meeting future water demands, 2) many regions can be expected to increase reliance on non-renewable groundwater, water reuse, and desalinated water, but they also highlight an important role for development and deployment of water conservation technologies and practices.  相似文献   

2.
《Journal of public economics》2006,90(10-11):1939-1954
Shifting of income between the corporate and the personal income tax bases in response to tax incentives is the premise of the literature on taxation and organizational form. Empirical evidence of income shifting is, however, merely circumstantial. Using a unique panel of high-frequency VAT data from Israel, we trace the footprints of income shifting through incorporation by high-income individuals who convert their labor income into less-taxed dividends. A rise in the personal income tax rates resulted in more than 4500 companies–a 5% addition to the corporate sector–being registered in the 12 months following the tax change, mainly by self-employed professionals in the industries of business activities and health services; behavioral response to taxation was found only in the top percentile of the income distribution.  相似文献   

3.
Optimal capital taxes may be positive in the steady state in Ramsey models with an incomplete set of factor taxes. I show this possibility crucially depends on how fiscal policy is constrained at date t = 0. If the government is barred from manipulating the value of initial assets, the Chamley–Judd result reappears: the optimal capital tax is always zero in the steady state.  相似文献   

4.
In rapidly growing urban areas of developing countries, infrastructure has not been able to cope with population growth. Informal water businesses fulfill unmet water supply needs, yet little is understood about this sector. This paper presents data gathered from quantitative interviews with informal water business operators (n = 260) in Kisumu, Kenya, collected during the dry season. Sales volume, location, resource use, and cost were analyzed by using material flow accounting and spatial analysis tools. Estimates show that over 76% of the city's water is consumed by less than 10% of the population who have water piped into their dwellings. The remainder of the population relies on a combination of water sources, including water purchased directly from kiosks (1.5 million m3 per day) and delivered by hand-drawn water-carts (0.75 million m3 per day). Energy audits were performed to compare energy use among various water sources in the city. Water delivery by truck is the highest per cubic meter energy demand (35 MJ/m3), while the city's tap water has the highest energy use overall (21,000 MJ/day). We group kiosks by neighborhood and compare sales volume and cost with neighborhood-level population data. Contrary to popular belief, we do not find evidence of price gouging; the lowest prices are charged in the highest-demand low-income area. We also see that the informal sector is sensitive to demand, as the number of private boreholes that serve as community water collection points are much larger where demand is greatest.  相似文献   

5.
Several technology and fuel options could be used to lower the strong oil dependence of the transportation sector. To formulate policies and to cost-effectively meet oil reduction objectives, assessments and comparisons of the long-term economic performances of different technology trajectories are essential. In this work, the energy and technology costs associated with reducing oil consumption in passenger cars in Sweden are calculated for a number of possible future transport fuel pathways and for different energy prices and climate policies. An optimisation model is applied in a simulatory multiple-run approach for this purpose. The model encompasses the transportation sector, as well as the stationary energy system. In terms of results, a methanol-based pathway gives incremental system costs in the range of ? 0.9–3 billion EUR for a complete phase-out of passenger car oil up to 2030. As compared to the methanol pathway, other biomass gasification-based fuel pathways involve additional incremental system costs in the region of 3 billion EUR, whereas ethanol- and electricity-based pathways give additional incremental system costs of 4–5 billion EUR. At lower oil reduction levels, the cost differences between the pathways are smaller and the electricity-based pathway is significantly more cost-competitive.  相似文献   

6.
In this paper, we explore the innovation growth of 200 mm and 300 mm silicon wafers from Taiwan. Using the historic data, we simulate the growth of the area of 200 mm and 300 mm silicon wafers manufactured in Taiwan by the competitive Lotka–Volterra model. The parameters in the Lotka–Volterra model estimated with the realistic data are obtained numerically. The dynamic growth of competitive relationship between 200 mm silicon wafers and 300 mm silicon wafers is then analyzed. To prove the performance of the model, we further compare the famous Bass model and the Lotka–Volterra model. We also perform the equilibrium analysis to determine the long-term stability state in the simulation trajectory. Our research exhibits that 200 mm silicon wafers and 300 mm silicon wafers show a prey–predator relationship under the assumption of natural competition in the global semiconductor market. From a managerial perspective, the coefficients in the Lotka–Volterra model of exponential growth, self-interaction and cross-interaction represent the strength of product attractiveness, niche capacity and interaction for two competition products. We also find that there exists a stable equilibrium state for 200 mm silicon wafers and 300 mm silicon wafers. The prey 200 mm generation does not disappear completely; it finally settles to a constant market alongside the predator 300 mm generation.  相似文献   

7.
This study estimates the reform effects of a reduction in statutory sick pay levels on sickness absence behavior and labor costs. German federal law reduced the legal obligation of German employers to provide 100% continued wage pay for up to six weeks per sickness episode. In 1996 statutory sick pay was decreased to 80% of foregone gross wages. Within the reform's target group – private sector employees – this measure increased the proportion of employees having zero days of absence between 6 and 8%. Quantile regression estimates indicate that employees with up to 5.5 annual absence days reduced their days of absence by about 12%. Extended analyses suggest that in industries that enforced the cut, behavioral effects were about twice as large. We show that the direct labor cost savings effect stemming from the cut in replacement levels clearly exceeds the indirect effect due to the decrease in absenteeism. Our calculations about the total decrease in labor costs are very much in line with official data which suggest that total employer-provided sick pay decreased by 6.7% or €1.7 billion per year.  相似文献   

8.
This paper investigates long-term returns from unemployment compensation, exploiting variation from the UK JSA reform of 1996, which implied a major increase in job search requirements for eligibility and in the related administrative hurdle. Search theory predicts that such changes should raise the proportion of nonclaimant nonemployed, with consequences on search effort and labor market attachment, and lower the reservation wage of the unemployed, with negative effects on post-unemployment wages. I test these ideas on longitudinal data from social security records (LLMDB). Using a difference in differences approach, I find that individuals who start an unemployment spell soon after JSA introduction, as opposed to 6 months earlier, are 2.5–3% more likely to move from unemployment into Incapacity Benefits spells, and 4–5% less likely to have positive earnings in the following year. This latter employment effect only vanishes 4 years after the initial unemployment shock. Also, annual earnings for the treated individuals are lower than for the non-treated. These results suggest that while tighter search requirements were successful in moving individuals off unemployment benefits, they were not successful in moving them onto stable or better jobs, with fairly long-lasting unintended consequences on a number of labor market outcomes.  相似文献   

9.
Recent reforms to radio spectrum regulation have sparked controversy over the respective merits of two mutually exclusive liberalization regimes: property rights and commons. This debate is restrictive because it is largely incomplete and misunderstood. It is also costly in terms of opposition and delays to reforms. Goals of efficient spectrum allocation are better served by a wider policy toolkit, inclusive of hybrid and intermediary regimes. In this article I sketch the contours of a ‘spectrum of spectrum regimes’, triangulating regulatory, private ownership and unlicensed approaches. I illustrate this triangulated model, which I then apply to confront allocative decisions in digital dividend policy, such as the FCC’s open access clause in the 700 MHz auction and Ofcom’s current review of UHF spectrum release in the 800 MHz band.  相似文献   

10.
Aiming at studying soil conservation function of alpine grassland in the Qinghai–Tibet Plateau, this paper simulated soil erosion changes under different degrees of human disturbance in a wind tunnel laboratory. Three types of grasslands were selected, which include alpine meadow (QH-1), alpine steppe meadow (QH-2) and alpine steppe (QH-3), and the soil erosion rate was taken as the index to measure soil conservation function. The experimental results show that the soil erosion rates of three grassland samples increase with wind velocity under different treatments but the increment of erosion rate varied greatly. Under original status, soil erosion rates are in turn QH-1 < QH-2 < QH-3, which indicates that the soil conservation services are QH-1 > QH-2 > QH-3. When the aboveground vegetation was cut, the soil erosion rate change of QH-1 is the same as that of QH-3 and compared with the original status both of them changed a little. And when the root system was destroyed the erosion rates range in turn as QH-1 < QH-2 < QH-3. So the data suggest that soil conservation service for the three types of grasslands should be QH-1 > QH-2 > QH-3. The economic values of soil conservation were estimated, which include the values of organic carbon fixation, nutrient retention and reducing soil disuse.  相似文献   

11.
This paper analyzes the role of endogenous property rights in the development of an open resource-based economy. I incorporate renewable resources and endogenous decisions on property rights into a convex growth model with the formal and informal sectors. I find that along the transition path to steady state, property rights enforcement is not constant but improves with time as well as involves intermediate property rights specification (between open access and perfect property rights). International trade and labor market are driving these endogenous changes. Property rights improve with favorable terms of trade when the economy exports resource services and stronger property rights help maintain the resource stock by deterring illegal harvest. This pushes labor away from the informal harvest sector toward greater participation in the formal sector of the economy. In turn, more labor participation in the formal sector along with capital formation increase the country’s output and consumption. Overall, with an open economy and well-functioning institutions, renewable resources have a positive impact on economic growth.  相似文献   

12.
《Journal of public economics》2006,90(6-7):1251-1262
This paper argues that, in models with heterogeneous agents, the concept of the marginal cost of public funds (MCPF) will only be useful if it is compared with an analogous concept for the benefit side. The MCPF does not assume a unique value and is not particularly illuminating in and out of itself. Also gone is the benchmark status of MCPF = 1. Turning to the provision of public goods, using a mechanism design approach, the paper constructs a two-stage proof for Kaplow's [Kaplow, L., 1996. The optimal supply of public goods and the distortionary cost of taxation. National Tax Journal 49, 513–533.] proposition concerning the “irrelevance” of labor supply and distributional concerns in public good provision. This highlights the two fundamental ingredients for his result. First, the provision of public goods per se, when it satisfies the Samuelson's rule, is only potentially Pareto-improving. Second, the actual Pareto improvement will materialize when, or if, one reforms the income tax structure. If the reform is not forthcoming, the decision on public goods provision must rely on redistributional concerns. Finally, the paper generalizes Broadway and Keen's [Boadway, R., Keen, M., 1993. Public goods, self-selection and optimal income taxation. International Economic Review 34, 463–478.] result to a model with many types of agents, many private goods and without making any assumptions regarding which self-selection constraints are or are not binding.  相似文献   

13.
This paper presents a new method to estimate the fractional differencing parameters in the SARFIMA model. A technique of split cosine bell tapering is suggested to improve the EGPH method. The simulation study shows that the optimal split proportion and bandwidth for the EGPH with split cosine bell tapering method respectively are p = 0.1 and b = 0.9. The new method with the optimal parameters outperforms the EGPH and EGPH with cosine bell tapering. We further applied the EGPH method to estimate intraday volume series and high-frequency absolute return data. The results show that the seasonal fractionally differencing parameters are all estimated to be large, while the nonseasonal fractionally differencing parameters are all very small. This indicates that their long memory property may be mainly caused by the structure of long-range dependence at the seasonal lags instead of dependence at the nonseasonal lags.  相似文献   

14.
This article challenges some of the assumptions underpinning the UN programme to Reduce Emissions from Deforestation and forest Degradation (REDD +) in developing countries. Firstly, it argues that the cost-effectiveness of REDD + may have been exaggerated as current estimates ignore some cost categories as well as the evolution of drivers. Whilst REDD + remains a ‘low-hanging fruit’ for climate mitigation, if all costs were included estimates would be at the high end of the currently accepted range. Secondly, the article highlights that REDD + will be affected by a large funding gap at least until the entry into force of a new climate protocol in 2020. This gap is due as much to the poor status of public finances in donor countries as to the languishing state of carbon markets, and it calls for a revision of the assumptions regarding the design of the programme. Finally, it is advocated that, in order to contribute to the development of the programme, economic research on REDD + should consider different policy options, assessing their efficiency and identifying measures that increase their cost-effectiveness.  相似文献   

15.
This study attempts to re-investigate the production structure change for the Malaysian economy through changes in the A and (I  A) 1 matrices over the period 1980–2005, when the planners formulated and implemented nine plans so far. Five input–output tables were published by the Department of Statistics in Malaysia for the period under study. A structural change method was carried out to analyze and assess the changes in economic efficiency. This comparative study focuses on changes in the economic structure with different levels of development over time (1980–2005). The change in the economic structure is decomposed into two initial components (technology and total output). In accordance with the results, there appear to be similarities over time in the national structure of production patterns of intermediate use of commodities. Also, the results clearly indicate a rather remarkable degree of commonality in the patterns of growth processes, with more significant differences among sectors than between tables. However, the changes within sectors, and the Malaysian table as a whole, seem to result from changes in the level of the efficiency. Technical relationship seems to have remained relatively unchanged. It is clear that the economy has not moved fast enough forward, and does not seem to be geared by, the type of exports that may sustain a dynamic industrial development, based on external markets. New evidence is revealed in this study: the efficiency degree between demand and supply side for the Malaysian economy still remain weak and changeable over the period of study.  相似文献   

16.
This study evaluates the directional accuracy of production managers' forecasts by using a new market-timing test. By extending the directional analysis to the 4 × 4 case, this study investigates whether Japanese production managers' forecasts correctly predict turning points in production across different industries. This fills a gap in the literature that focused on predicting increase/decrease or acceleration/deceleration using directional analysis of the 2 × 2 case. It also illustrates its merit over the 2 × 2 case. This study shows that majority of the forecasts are not useful in predicting turning points in production; however, they are useful in predicting increase/decrease in production. Our findings suggest that the production managers' forecasts serve as early qualitative information of expansion and contraction on the Japanese economy and their accuracy does not differ by phases of business cycles.  相似文献   

17.
《European Economic Review》2001,45(4-6):890-904
We exploit the changes in the distribution of family income to estimate the effect of parental resources on college education. Our strategy exploits the fact that families at the bottom of the income distribution were much poorer in the 1990s than they were in the 1970s, while the opposite is true for families in the top quartile of the distribution.  Our estimates suggest large effects of family income on enrollments.  For example, we find that a 10 percent increase in family income is associated with a 1.4 percent increase in the probability of attending a four-year college.  相似文献   

18.
Conventional tests for the environmental Kuznets curve (EKC) hypothesis mostly apply a quadratic equation in modeling the non-linear relationship between environmental indices (such as air pollutants) and welfare measures (such as income per capita). If their inverted-U shaped pattern is empirically accepted with two significant regressors, the income per capita and its square transformation, the EKC hypothesis is supported. Using an OECD sample, this paper shows that the validity of testing the EKC hypothesis is sensitive to how we transform income non-linearly in sulfur and carbon EKC regressions. This paper carries out experiments on different powers of γ for transforming income non-linearly and concludes that only when 0 < γ < 1 and 1 < γ < 2 will the EKC regression demonstrate a testable non-linear cointegration relationship between the two air pollutants and income per capita. In the generalized EKC regressions estimated in this paper, although we find sulfur and carbon EKC patterns in the OECD sample, none of the EKC regressions using different γ is a cointegrating equation. This finding implies an inside critique to the EKC literature that failure of cointegration of the conventional EKC regression is not because of using the quadratic functional form, but because of the fundamentally spurious relationship between the trends of pollutants and income levels.  相似文献   

19.
《Journal of public economics》2006,90(8-9):1745-1763
This paper analyzes the effects of spillovers on the equilibrium population distribution across jurisdictions in a local public good economy with free mobility. Spillovers are parametrized by a matrix [αij] where αij  [0, 1]. When spillovers are symmetric and close to 0 or 1 (pure local public goods and pure public goods), all equilibrium jurisdiction structures are symmetric. However, any population distribution can be sustained in equilibrium for some value of the spillover parameter α. In the class of utility functions with additive externalities, we identify the unique family of utility functions for which equilibria are symmetric except for an isolated value of α. This is a class of utility functions which are linear in the public good and a power function of the private good, u(c, γ) =  A(1  c)β + γ. With this specification of utility, we show that an increase in α results in a more fragmented equilibrium population distribution, and that when spillovers are asymmetric and large, a jurisdiction which is more centrally located (i.e. benefits more from the public goods provided in other jurisdictions) has a larger population in equilibrium.  相似文献   

20.
This paper presents a detailed analysis of the activities in which ocean energy public funding in the UK and the U.S. has been spent. It conducts a direct comparison of funding from the U.S. Department of Energy (DoE) with that from the UK and Scottish Governments. UK investment in the sector has been relatively sustained and has increased since 2002. Almost $295 million has been spent in total, across multiple funding bodies. U.S. spending began with the establishment of the Marine Hydrokinetic division of the DoE Water Power Programme in 2008, which has administered all non-defence federal public funding for the sector. U.S. funding has steadily increased since 2008, with the total funding approaching $92 million.Approximately 40% of total U.S. spending has been on underpinning R&D activities, compared to 20% in the UK which has had a larger focus on funding full scale test infrastructure and related deployment activities. Whilst the U.S. has seen steadily increasing funding for all activities to support the sector, UK funding for deployment activities, especially test centre infrastructure and demonstration activities, has not been sustained and has had significant peaks and troughs in recent years as funding programmes and initiatives have started and finished.  相似文献   

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