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71.
Single-objective-based decision-tree analysis has been extensively and successfully used in numerous decision-making problems since its formal introduction by Howard Raiffa more than two decades ago. This paper extends the traditional methodology to incorporate multiple noncommensurate objective functions and use of the conditional expected value of the risk of extreme and catastrophic events. The proposed methodology considers the cases where (a) a finite number of actions are available at each decision node and (b) discrete or continuous states of nature can be presented at each chance node. The proposed extension of decision-tree analysis is introduced through an example problem that leads the reader step-by-step into the methodological procedure. The example problem builds on flood warning systems. Two noncommensurate objectives—the loss of lives and the loss of property (including monetary costs of the flood warning system)–are incorporated into the decision tree. In addition, two risk measures—the common expected value and the conditional expected value of extreme and catastrophic events—are quantified and are also incorporated into the decision-making process. Theoretical difficulties associated with the stage-wise calculation of conditional expected values are identified and certain simplifying assumptions are made for computational tractibility. In particular, it is revealed that decisions concerning experimentation have a very interesting impact on the noninferior solution set of options—a phenomenon that has no equivalence in the single-objective case. 相似文献
72.
提出了一种时变参数混沌同步保密通信方法,极大地提高了混沌同步的通信保密性,使目前的各种破译手段均无法破译该方法;并基于Chua电路进行了仿真。采用该方法进行混沌同步通信,击败了目前各种破译手段的攻击,证实了其高保密性。 相似文献
73.
We state sufficient conditions for asymptotic normality of convergent estimates of the conditional mode, irrespective of data dependence, and give an application to α-mixing stationary processes. 相似文献
74.
Noteworthy connections among conglomerability, countable additivity and coherence are discussed in detail, reaching the conclusion
that nonconglomerable conditional probabilities must not be doomed and play a significant role in statistical inference.
Extended and updated version of a contributed paper presented at the International Conference on “Information Processing and
Management of Uncertainty in knowledge-based systems”, IPMU 2004, Perugia, Italy. 相似文献
75.
综合分析近20年来经济计量建模理论在分数维长记忆时间序列的分析建模、协整(同积)理论的建立以及刻画经济金融波动的时变条件异方差过程的分析建模三个方面发生的重要变化以及在这些领域,Granger和Engle做出的极其重要贡献,并提出新的发展方向和领域。 相似文献
76.
Graphical Models for Composable Finite Markov Processes 总被引:1,自引:0,他引:1
VANESSA DIDELEZ 《Scandinavian Journal of Statistics》2007,34(1):169-185
Abstract. Composable Markov processes were introduced by Schweder (1970) in order to capture the idea that a process can be composed of different components where some of these only depend on a subset of the other components. Here we propose a graphical representation of this kind of dependence which has been called 'local dependence'. It is shown that the graph allows to read off further independencies characterizing the underlying Markov process. Also, some standard methods for inference are adapted to exploit the graphical representation, e.g. for testing local independence. 相似文献
77.
Given observations on an m × n lattice, approximate maximum likelihood estimates are derived for a family of models including direct covariance, spatial moving average, conditional autoregressive and simultaneous autoregressive models. The approach involves expressing the (approximate) covariance matrix of the observed variables in terms of a linear combination of neighbour relationship matrices, raised to a power. The structure is such that the eigenvectors of the covariance matrix are independent of the parameters of interest. This result leads to a simple Fisher scoring type algorithm for estimating the parameters. The ideas are illustrated by fitting models to some remotely sensed data. 相似文献
78.
供应突发事件下,引入条件风险值(conditional value at risk-CVa R)刻画了零售商的运营目标,构建了收益共享契约下的供应链订货模型,着重研究了CVa R下的供应链协调及零售商最优订货量对供应商可靠性及对其自身的风险规避系数的敏感性。研究表明:收益共享契约具有一定的鲁棒性,能协调突发事件风险下的供应链;风险规避型零售商的最优订货量总是不小于风险中性情况,且风险规避程度越高,订货量越大;最优订货量对供应商可靠性均值的敏感性不依赖于零售商的风险规避程度,且均值越小,最优订货量越大,这与风险中性情况是类似的;最优订货量对供应商可靠性标准差的敏感性则依赖于零售商的风险规避程度,当零售商的风险规避程度较高时,供应可靠性标准差越大,最优订货量越大,这与风险中性情况是相反的。 相似文献
79.
副词“才”表示“方始”,即在某个时间点,某个事件从无到有。强调事件在这个时间点而不是这个时间点之前实现,并且,从事件实现到说话时的时间段相对较短。当客观时间量在句子中出现,“才”进一步虚化表达主观量:前指表达主观大量,后指表达主观小量。“T才P”是限制条件的肯定P,这个条件就是T,用于肯定句可以用转折来表示,而条件之外则不能肯定P。名词语进入“才 名词语”这一句法格式的条件是:名词本身有明显的序列推移性或者在某种特定条件下能进入某个排序中。 相似文献
80.
刘冬梅 《辽宁医学院学报(社会科学版)》2006,(1)
从语义方面考察俄语关联词который及кто,通过量化分析的方法,在语义上对它们互换的可能性进行比较深入的探讨,显得尤其重要。который,кто在具体语境中都可以表示“存在指代”的意义,当语法特征和修辞特征相同时,它们通常可互换使用。 相似文献