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41.
针对由单制造商和单销售商组成的供应链,提出了供应链双方需求信息对称情况下的激励机制模型,并在此基础上建立了供应链双方在需求信息不对称情况下的运作策略模型。制造商通过折扣,运用激励相容机制使销售商诚实申报需求信息,使得供应链利润最大化的同时供应链成员实现双赢。数字试验结果表明:①所提策略是有效的;②该策略不仅能提高制造商利润,而且也能改善销售商的利润。 相似文献
42.
Jon M. Conrad 《Journal of Bioeconomics》1999,1(2):205-217
Consider an offshore fishing grounds of size K. Suppose the grounds has been overfished to the point that net revenue has been driven to zero and the fishery is in open access equilibrium at (X, Y). A marine sanctuary, where fishing is prohibited, is then created. Suppose the marine sanctuary is of size K2 and that fishing is allowed on a smaller grounds, now of size K1, where K1 + K2 = K. In the first, deterministic, model, the present value of net revenue from the grounds-sanctuary system is maximized subject to migration (diffusion) of fish from the sanctuary to the grounds. The size of the sanctuary is varied, the system is re-optimized, and the populations levels, harvest, and value of the fishery is compared to the 'no-sanctuary' optimum, and the open access equilibrium. In the deterministic model, a marine sanctuary reduces the present value of the fishery relative to the 'ideal' of optimal management of the original grounds. In the second model net growth is subject to stochastic fluctuation. Simulation demonstrates the ability of a marine sanctuary to reduce the variation in biomass on the fishing grounds. Variance reduction in fishable biomass is examined for different-sized sanctuaries when net growth on the grounds and in the sanctuary fluctuate independently and when they are perfectly correlated. For the stochastic model of this paper, sanctuaries ranging in size from 60 to 40% of the original grounds (0.6 K2/K 0.4) had the ability to lower variation in fishable biomass compared to the no sanctuary case. For a sanctuary equal to or greater than 70% of the original grounds (K2 0.7K), net revenue would be nonpositive and there would be no incentive to fish. 相似文献
43.
We use stochastic dominance to test whether investor should prefer riskier securities as the investment horizon lengthens. Return distributions for stocks, bonds, and U.S. Treasury bills are generated for holding periods of one to 25 years by simulation. For each holding period, stochastic dominance tests are run to establish preferences between the alternative security classes. Contrary to previous mean-variance based studies, we find no evidence that high-risk securities (stocks) dominate low-risk securities (bonds, Treasury bills) as the investment horizon lengthens. However, we do find that corporate bonds systematically dominate government bonds. 相似文献
44.
Valuing high-dimensional options has many important applications in finance but when the true distributions are unknown or
complex, numerical approximations must be used. Approximation methods based on Monte-Carlo simulation show a steep trade-off
between estimation accuracy and computational efficiency. This article presents an alternative semi-analytic approximation
method for pricing options on the maximum or minimum of multiple assets with unknown distributions. Computational efficiency
is shown to improve significantly without sacrificing estimation accuracy. The method is illustrated with applications to
options on underlying assets with mean-reverting prices, time-dependent correlations, and stochastic volatility
The authors would like to thank the two anonymous referees, the associate editor, and Dr. Jess H. Chua at the University of
Calgary for valuable comments and insights on this research. This research was partly supported by NUS grant R-146-000-059-112 相似文献
45.
46.
A detailed analysis of the Least Squares Monte-Carlo (LSM) approach to American option valuation suggested in Longstaff and Schwartz (2001) is performed. We compare the specification of the cross-sectional regressions with Laguerre polynomials used in Longstaff and Schwartz (2001) with alternative specifications and show that some of these have numerically better properties. Furthermore, each of these specifications leads to a trade-off between the time used to calculate a price and the precision of that price. Comparing the method-specific trade-offs reveals that a modified specification using ordinary monomials is preferred over the specification based on Laguerre polynomials. Next, we generalize the pricing problem by considering options on multiple assets and we show that the LSM method can be implemented easily for dimensions as high as ten or more. Furthermore, we show that the LSM method is computationally more efficient than existing numerical methods. In particular, when the number of assets is high, say five, Finite Difference methods are infeasible, and we show that our modified LSM method is superior to the Binomial Model. 相似文献
47.
马玲 《石油工业技术监督》2005,21(9):12-14
介绍了燃料乙醇仿真系统软、硬件的结构,着重阐明了它的设计思想和技术特色;标准、适用、灵活是该系统的最重要的特点;实现了全流程的仿真;该系统既可用于培训,还可用于运行指导. 相似文献
48.
In this paper, we study the family of renewal shot-noise processes. The Feynmann–Kac formula is obtained based on the piecewise deterministic Markov process theory and the martingale methodology. We then derive the Laplace transforms of the conditional moments and asymptotic moments of the processes. In general, by inverting the Laplace transforms, the asymptotic moments and the first conditional moments can be derived explicitly; however, other conditional moments may need to be estimated numerically. As an example, we develop a very efficient and general algorithm of Monte Carlo exact simulation for estimating the second conditional moments. The results can be then easily transformed to the counterparts of discounted aggregate claims for insurance applications, and we apply the first two conditional moments for the actuarial net premium calculation. Similarly, they can also be applied to credit risk and reliability modelling. Numerical examples with four distribution choices for interarrival times are provided to illustrate how the models can be implemented. 相似文献
49.
50.
经济资本(EC)是在既定期间和置信水平下,公司根据实际承担的风险计算的用以吸收非预期损失的资本额度,目前市场风险是整体经济资本测算体系中最为突出的风险.根据当前保险运营与资产投资的比例特征,同时对资产端与负债端建立市场风险投资模型,采用嵌套随机模拟方法进行两阶段情景生成,度量未来一年内不同风险测度下的市场风险经济资本需求,并对比不同情景数量下的测算稳定性.结果证明:随着内部或外部情景模拟次数的增加,市场风险经济资本测算结果对于极端风险的预测趋于稳定,在内外部情景数量乘积相同时运算时间基本一致.当内外部两阶段情景生成参数差异较大的情形下,应适当增加情景生成数量,以确保对于极端风险预测的准确性. 相似文献