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101.
This paper makes a preliminary assessment of how the current structure for the distribution of UK National Lottery funds affects the promise of net additionality for the designated 'good causes'. Indifference analysis demonstrates that the funding structure is optimal in these terms. However, the measurement of net additionality is highly problematic and involves both quantitative and qualitative techniques. Whilst a preliminary comparison with Ireland shows that the UK system is in a better position to achieve net additionality through its accountability and transparency, net additionality could still be only a relatively small proportion of the dedicated Lottery money, depending on the behaviour of politicians, local authorities, other interest groups, and the distribution boards themselves.  相似文献   
102.
We provide a framework in which we link the valuation and assetallocation policies of defined benefits plans with the lifetimemarginal productivity schedule of the worker and the pensionplan formula. In turn, we examine the retirement policies thatare implied by the primitives of the model and the value ofpension obligations. Our model provides an explicit valuationformula for a stylized defined benefits plan. The optimal assetallocation policies consist of the replicating portfolio independentof the pension liabilities. We show that the worker with retirewhen the ratio of pension benefits to current wages reachesa critical value which depends on the parameters of the pensionplan and the discount rate. Using numerical techniques we analyzethe feedback effect of retirement policies on the valuationof plans and on the asset allocation decisions.  相似文献   
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104.
In this article we compare three models of the stochastic behavior of commodity prices that take into account mean reversion, in terms of their ability to price existing futures contracts, and their implication with respect to the valuation of other financial and real assets. The first model is a simple one-factor model in which the logarithm of the spot price of the commodity is assumed to follow a mean reverting process. The second model takes into account a second stochastic factor, the convenience yield of the commodity, which is assumed to follow a mean reverting process. Finally, the third model also includes stochastic interest rates. The Kalman filter methodology is used to estimate the parameters of the three models for two commercial commodities, copper and oil, and one precious metal, gold. The analysis reveals strong mean reversion in the commercial commodity prices. Using the estimated parameters, we analyze the implications of the models for the term structure of futures prices and volatilities beyond the observed contracts, and for hedging contracts for future delivery. Finally, we analyze the implications of the models for capital budgeting decisions.  相似文献   
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107.
The paper seeks to evaluate the evidence on the employment effectsof the collective working-time reductions in Europe over thepast 20 years. While theoretical analyses produce contradictoryassessments, most empirical studies show positive employmenteffects but take insufficient account of these conditions underwhich the reductions in working time were implemented. Theseconditions for the success of collective working-time reductionsinclude an active training policy designed to minimise skillshortages in the labour market, the modernisation of work organisation,wage increases in conjunction with productivity gains and amore equal income distribution.  相似文献   
108.
Hydrogeologists always look for reliable techniques to determine the hydraulic conductivity of the aquifers with which they are concerned, for better groundwater management and conservation. The use of grain size distribution for unconsolidated aquifer materials is considered feasible and sound. Several empirical equations to calculate hydraulic conductivity using grain size distribution are well established in the literature. The present paper describes a computer program, HYDCOND, which is designed to calculate hydraulic conductivity using grain size data. In addition, the program calculates grain size statistics and classifies the aquifer materials in terms of their main size percentage. HYDCOND is menu-driven, interactive and user friendly program. It was tested extensively and successfully using materials from Minjur aquifer in central Saudi Arabia. The results were found to be reliable and comparable to those obtained using other, costly techniques. HYDCOND can be implemented successfully to calculate hydraulic conductivity in all types of aquifers in Saudi Arabia and other regions of the world.  相似文献   
109.
The linkage between macroeconomic policies and agricultural commodity trade has become an important research issue of agricultural economists. This paper investigates the macroeconomic linkage of soybean trade competition between the exporting countries of the United States, Brazil, and Argentina in the EC-12 and Japan import markets. It is argued that U.S. monetary growth may have important impacts on the competitive position of U.S. soybean exports through exchange rates. Two relationships are investigated: (a) the effects of U.S. monetary growth on the agricultural trade weighted exchange rates, and (b) the responsiveness of agricultural commodity prices and U.S. exports to exchange rate movements. Results indicate that a weak dollar increases imports of soybeans and soymeal significantly which serves to increase the equilibrium world price and increase both U.S. and Brazil/Argentina exports in the long run. However, during periods of more expansionary U.S. monetary policy there is little evidence of significant increases in market share position for U.S. soybeans and soymeal in world markets.  相似文献   
110.
S. B. Kim  D. S. Bai 《Metrika》1992,39(1):85-93
Summary Economic design of one-sided screening procedures for improving outgoing product quality based on a screening variable is considered for the case with all parameters unknown. It is assumed that the performance and screening variables are jointly normally distributed and that costs are incurred by screening inspection, acceptance of an imperfect item, and disposition of a rejected one. A method for finding optimal cutoff value based on the predictive distribution is presented.  相似文献   
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