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21.
The Incredible Economics of Geoengineering   总被引:3,自引:1,他引:2  
The focus of climate policy so far has been on reducing the accumulation of greenhouse gases. That approach, however, requires broad international cooperation and, being expensive, has been hindered by free riding; so far, little action has been taken. An alternative approach is to counteract climate change by reducing the amount of solar radiation that strikes the Earth—“geoengineering.” In contrast to emission reductions, this approach is inexpensive and can be undertaken by a single country, unilaterally. But geoengineering also has worrying consequences: it may harm some countries; it would not address ocean acidification; it would pose new risks. The fundamental challenge posed by this new technology is not free riding but governance: who should decide if and under what circumstances geoengineering should be used?  相似文献   
22.
This article examines the economic outcome of 2006 and builds a forecast for 2007–2010. The medium-term development risks of the Russian economy are analyzed.  相似文献   
23.
An issue in the pricing of contingent claims is whether to account for consumption risk. This is relevant for contingent claims on stock indices, such as the FTSE 100 share price index, as investor’s desire for smooth consumption is often used to explain risk premiums on stock market portfolios, but is not used to explain risk premiums on contingent claims themselves. This paper addresses this fundamental question by allowing for consumption in an economy to be correlated with returns. Daily data on the FTSE 100 share price index are used to compare three option pricing models: the Black–Scholes option pricing model, a GARCH (1, 1) model priced under a risk-neutral framework, and a GARCH (1, 1) model priced under systematic consumption risk. The findings are that accounting for systematic consumption risk only provides improved accuracy for in-the-money call options. When the correlation between consumption and returns increases, the model that accounts for consumption risk will produce lower call option prices than observed prices for in-the-money call options. These results combined imply that the potential consumption-related premium in the market for contingent claims is constant in the case of FTSE 100 index options.  相似文献   
24.
The purpose of this essay is to examine psychoanalytically Argyris and Schon's contributions to organization theory and intervention. The author focuses his attention on the problem of individual and organizational resistance to change in the light of Argyris and Schon's cognitive psychological assumptions about learning, reasoning, and effectiveness.  相似文献   
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This paper applies principles of transition to land tenure and squatting in South Africa. Political transition in South Africa reassigned political property rights, which produced contestable, and rent‐seeking incentives for squatting as a means to privatize land and redistribute wealth. Government failure to establish and protect private property rights in a squatter camp resulted in common‐pool problems that resisted private and public resolution with consequent rent dissipation and social loss. In response to this retreat from duty, informal agents emerged to claim their own share of the prize. Without enforceable rules of capture, the growth of squatter camps in South Africa will continue. JEL classification: D7, H8, K1, K4, R1, R4.  相似文献   
28.
The rise of environmentalism in the past decade has become a major transforming force in pollutive and hazard prone industries. Corporate environmental responsiveness is not simply a peripheral and one of the many ‘social’ or ‘ethical’ issues facing business. It is becoming a central concern for competitiveness, productivity, and profitability. It is creating strategic transformation of companies in a diverse range of industries such as, Autos, Chemicals, Oil, Fast Foods, Power Generation, Pharmaceuticals, etc. The process of environmentally directed self-renewal, called ‘greenewal’ here, affects all aspects of companies. It implies changes in products, production systems, waste management practices and internal systems. It seeks to make companies simultaneously more competitive and environmentally responsible. This paper describes the pressures of and responses to environmentalism in a selected set of industries. It examines the processes of greenewal that companies are undergoing. It identifies implications for strategic greening of firms.  相似文献   
29.
Medic (Medicago spp.) pastures are widely grown in rotation with dryland cereal crops in Mediterranean climate zones of Australia. Attempts since the 1960's to introduce this system to Mediterranean west Asia and north Africa (the native region of medic) have not lead to significant adoption; farmers in the region recognize medic, but as a weed and natural pasture plant. This first detailed economic evaluation of the rotational medic system was conducted using a whole-farm linear programming model based on the agricultural system of north-west Syria. The model represents in detail impacts of rotation on yields, labor requirements of alternative farm activities, availability of family and hired labor, subsistence income requirements, livestock feed sources and uses at different times and a choice of sheep stocking rates. Biological data for the analysis are based on a large six-year cropping and grazing experiment near Aleppo on terra-rossa soil with rainfall mainly in winter and averaging about 330 mm annually. The trial compared a dryland medic-wheat system and traditional two-year rotations of wheat with: fallow, watermelon, lentil and vetch. Results indicate that, given current prices and yields from the trial, medic is less profitable than traditional rotations. The model was used to investigate situations in which medic would be economically preferred. Selection of a medic rotation by the model was found to be particularly sensitive to the area of the farm and the price of labor. On small farms, labor availability per hectare is high, favouring the production of labor intensive crops such as lentil and watermelon. On larger farms, labor costs of these enterprises are substantial, increasing the relative profitability of medic, especially if labor prices increase. Interestingly, the relative desirability of medic is more sensitive to its impact on subsequent wheat crops than to the level of pasture production. We also found that modest increases in the prices of sheep products (especially milk) have a major impact on the economic performance of medic. These insights will allow improved focusing and targeting of future research and extension activities.  相似文献   
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