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111.
在DEA中有关输出与输入的比值的模型的探讨 总被引:1,自引:0,他引:1
吴文江 《数学的实践与认识》2009,39(10)
对以决策单元的输出与输入的比值为目标函数的多目标规划模型,证明了有关它与(弱)DEA有效(C2R)关系的三个定理. 相似文献
112.
Rik G.P. Frehen Roy P.M.M. Hoevenaars Franz C. Palm Peter C. Schotman 《Insurance: Mathematics and Economics》2008,42(3):1050-1061
The high value of the implicit option to choose a retirement date at which interest rates are particularly high and life annuities relatively cheap, leads to the possibility to introduce regret aversion in the retirement investment decision of defined contribution plan participants. As a remedy for regret aversion in retirement investment decisions, this paper develops and prices a lookback option on a life annuity contract. We determine a closed-form option value under the restriction that the option holder invests risklessly during the time to maturity of the option and without the guarantee that the exact amount of retirement wealth is converted into a life annuity at retirement. Thereafter the investment restriction is relaxed and the guarantee of exact conversion is imposed and the option is priced via Monte Carlo simulations in an economic environment with a stochastic discount factor. Option price sensitivities are determined via the pricing of alternative options. We find that the price of a lookback option, with a maturity of three years, amounts to 8%–9% of the wealth at the option issuance date. The option price is highly sensitive to the exercise price of the option, i.e. pricing alternative options (e.g. Asian) substantially lowers the price. Time to maturity and interest rate volatility are other important option price drivers. Asset allocation decisions and initial interest rates hardly affect the option price. 相似文献
113.
复合Poisson模型中“双界限”分红问题 总被引:2,自引:0,他引:2
引入了复合Poisson模型中的"双界限"分红模型,在这种模型中,当盈余超过上限时分红以不超过保费率的速率付出,低于下限后保费率增大.文中利用Gerber- Shiu函数来分析这种模型,先导出了Gerber-Shiu函数m_1,m_2,m_3满足的积分-微分方程,再给出m_1,m_2,m_3的解析表示,最后通过几步把Gerber-Shiu函数m(u;b_1,b)的解析式表示出来. 相似文献
114.
研究一类多阶段动态规划问题,给出了求最优解的方法.将这种多阶段动态规划应用于Turbo译码中,不仅可以减少运算量,还可以避免传统的Turbo译码算法需要进行指数运算以及其随着迭代次数的增加容易出现的数据溢出问题,因此是一种十分有效的方法,是对系统工程理论应用领域的拓宽. 相似文献
115.
116.
Computer-assisted optimization of chromatographic separations is still a fruitful activity. In fact, advances in computerized
data handling should make the application of systematic optimization strategies much easier. However, in most contemporary
applications, the optimization criterion is not considered to be a key issue (Vanbel, J Pharm Biomed, 21:603–610, 1999). In this paper, an update of the importance of selecting adequate criteria in chromatographic separation is presented. 相似文献
117.
Adam Krzemienowski Włodzimierz Ogryczak 《Computational Optimization and Applications》2005,32(1-2):133-160
A mathematical model of portfolio optimization is usually quantified with mean-risk models offering a lucid form of two criteria with possible trade-off analysis. In the classical Markowitz model the risk is measured by a variance, thus resulting in a quadratic programming model. Following Sharpe’s work on linear approximation to the mean-variance model, many attempts have been made to linearize the portfolio optimization problem. There were introduced several alternative risk measures which are computationally attractive as (for discrete random variables) they result in solving linear programming (LP) problems. Typical LP computable risk measures, like the mean absolute deviation (MAD) or the Gini’s mean absolute difference (GMD) are symmetric with respect to the below-mean and over-mean performances. The paper shows how the measures can be further combined to extend their modeling capabilities with respect to enhancement of the below-mean downside risk aversion. The relations of the below-mean downside stochastic dominance are formally introduced and the corresponding techniques to enhance risk measures are derived.The resulting mean-risk models generate efficient solutions with respect to second degree stochastic dominance, while at the same time preserving simplicity and LP computability of the original models. The models are tested on real-life historical data.The research was supported by the grant PBZ-KBN-016/P03/99 from The State Committee for Scientific Research. 相似文献
118.
119.
Mahdi Zarghami Ferenc Szidarovszky Reza Ardakanian 《Fuzzy Optimization and Decision Making》2008,7(1):1-15
All realistic Multi-Criteria Decision Making (MCDM) problems face various kinds of uncertainty. Since the evaluations of alternatives
with respect to the criteria are uncertain they will be assumed to have stochastic nature. To obtain the uncertain optimism
degree of the decision maker fuzzy linguistic quantifiers will be used. Then a new approach for fuzzy-stochastic modeling
of MCDM problems will be introduced by merging the stochastic and fuzzy approaches into the OWA operator. The results of the
new approach, entitled FSOWA, give the expected value and the variance of the combined goodness measure for each alternative.
Robust decision depends on the combined goodness measures of alternatives and also on the variations of these measures under
uncertainty. In order to combine these two characteristics a composite goodness measure will be defined. The theoretical results
will be illustrated in a watershed management problem. By using this measure will give more sensitive decisions to the stakeholders
whose optimism degrees are different than that of the decision maker. FSOWA can be used for robust decision making on the
competitive alternatives under uncertainty. 相似文献
120.
V. V. Podinovski 《Computational Mathematics and Mathematical Physics》2008,48(11):1981-1998
Multicriteria decision-making problems under bounded (above, below, or from both sides) continuous or discrete criteria are considered. Methods for comparing variants of solutions using the information accumulated in the form of interval estimates of replacing the values of some criteria by the values of others (such replacements are called tradeoffs; in other words, this can be considered as a compensation of the deterioration of some criteria by improving the values of others) are proposed along with simple consistency conditions of such information. The issue of constructing the set of nondominated variants is discussed. 相似文献