应急决策方案的动态调整方法研究

本文针对应急决策中方案的动态调整问题,提出了一种风险决策方法。首先,根据突发事件的情景演变特点,描述了应急决策中方案调整的问题和过程,并对不同方案之间的相关性进行分析;然后,阐述了调整方案的生成过程;进一步地,考虑调整方案对各级别突发事件的应急处置效果和应对损失、不同方案之间的转换成本等因素,给出了应急决策方案的动态调整方法;最后,通过算例说明了该方法的有效性和可行性。     

Screening alternatives graphically by an extended case-based distance approach

Screening is a helpful process of multiple criteria decision aid (MCDA) to reduce a larger set of alternatives into a smaller one containing the best alternatives; thereby, decision makers are able to concentrate on evaluating alternatives within a smaller set. Therefore, determining how to assist decision makers in screening is an important issue for MCDA. This study proposes an extended case-based distance approach incorporating the advantages of a case-based distance method, a mixed-integer programming approach of discriminant analysis, and a multidimensional scaling technique to help decision makers screen alternatives visually in MCDA. The proposed approach can screen alternatives by evaluating sets of cases selected by decision makers, providing visual aids to observe decision context, reducing the number of misclassifications, and improving multiple solution problems. An interactive screening procedure is also developed to provide flexibility so that decision makers can check and adjust screening results iteratively.     

R&D portfolio selection by using qualitative pairwise comparisons

A new multicriteria decision aid, QualScal, is applied to the problem of selecting an extramural Fisheries R&D portfolio in the Ministry of Agriculture, Fisheries and Food. QualScal has been developed for the situation where the characteristics of the decision alternatives cannot be readily quantified. The decision-maker is only required to state either indifference or preference for each pair of the alternatives. A map representing the preference structure of the decision maker is produced with the aid of an enhanced version of the traditional nonmetric multidimensional scaling procedure, capable of scaling disjoint subsets of alternatives. Averaged results for the group of decision-makers facilitate a discussion to determine a mutually acceptable portfolio.     

EVALUATING MULTIPLE CRITERIA—MODELS FOR TWO-CRITERIA SITUATIONS

A general procedure is given for evaluating various alternatives (e.g., investments, projects, systems, etc.) involving two criteria of evaluation. The method involves the detailed questioning of decision makers as to preferences between various combinations of pre-selected sets of alternatives under various conditions. From the responses to such questions, a mathematical function which can be applied repeatedly for implementing choices between other alternatives is established. An example of the application of the procedure is given, along with discussion of certain ramifications of the example. In addition to the specific application, potential extensions of the technique are discussed briefly.     

A case-based distance method for screening in multiple-criteria decision aid

Screening is a process of multiple-criteria decision aid (MCDA) in which a large set of alternatives is reduced to a smaller set that most likely contains the best choice. We propose screening using a distance model calibrated on the basis of the decision-maker's own judgement. Viewing MCDA as preference aggregation based on consequence data, we define consequence and preference expressions (values and weights) and describe how they are aggregated. Then we define screening and explain some of its properties. Using an appropriate definition of distance, our case-based distance method screens a set of alternatives using criterion weights and a distance threshold obtained by quadratic optimization using the decision-maker's selection of alternatives from a test set. This case-based method can elicit the decision maker's preferences more expeditiously and accurately than direct inquiry. An application in water supply planning is used to demonstrate the procedure.     

On the Rank-Based Selection Strategy for the Group Interview Problem*

For the so-called group interview problem in which several groups of choice alternatives are presented sequentially to the decision maker, the optimal selection strategy is derived that minimizes the expected rank of the selected choice or purchased product. For the case in which the sequence of groups can be rearranged by the decision maker, a simple heuristic procedure is proposed for obtaining a near-optimal sequence of groups, and the performance of the heuristic procedure in a Monte Carlo simulation is accessed. According to the heuristic procedure, the consumer is advised to visit smaller stores first and then move to larger stores later to increase the likelihood of finding a better product. Finally, the optimal selection strategy and the heuristic procedure are compared with those proposed by Chun, Moskowitz, and Plante (1993) and the problem of locating a new store in an area where there are several competing stores is discussed. The optimal selection strategy and the heuristic procedure can be applied to many sequential decision problems such as the consumer search and purchase process.     

A two-phase robot selection procedure

In this paper, a two-phase methodology is proposed for robot selection. In phase 1, data envelopment analysis is used as a means to determine the technically efficient robot alternatives, considering cost and technical performance parameters. Using data envelopment analysis permits us to consider the fact that the performance parameters specified by the vendors are generally unattainable in practice. In the second phase, a fuzzy robot selection algorithm is utilized to rank the technically efficient robots according to both predetermined objective criteria and additional vendor-related subjective criteria. The algorithm is based on calculating fuzzy suitability indices for the technically efficient robot alternatives, and then, ranking the fuzzy indices to select the best robot alternative. A comprehensive example is provided to illustrate the decision procedure. The algorithm proposed in here is also applicable to a broader area of decision problems, e.g. facility site selection, determination of the best CNC machine or flexible manufacturing system among a set of mutually exclusive alternatives.     

Analysis in support of strategic policy making

Policy making involves choice between alternatives in situations that are usually very complex. The process of choice in such situations is not such that a straightforward analytical procedure can be prescribed yielding a uniquely rational solution. However, decision problems arising in policy making situations can be investigated using methods based on recent developments in game and metagame theory. This methodology can form the basis of a rational decision structure of the type envisaged by Diesing that can be incorporated in the day-to-day work of most organizations.     

ON THE EQUIVALENCE OF TWO VERSIONS OF THE PRESENT VALUE PROCEDURE

The central issue in equipment investment analysis is the selection of the best of two or more alternatives. A common procedure is to first assume that for each alternative there is an infinite stream of identical pieces of equipment. The present value of the associated infinite stream of revenues and costs is calculated. Then the alternative having the highest present value (where revenues are positive and costs are negative) is selected. The assumption of the infinite stream, though computationally desirable, is not very palatable to the decision maker. In this paper we show that the above procedure is equivalent to using a criterion which is definitely more appealing. The author has found this “equivalence” result to be helpful in teaching the basic concepts of the present value procedure. Also the result should be of interest to practitioners involved in equipment investment decision making.     

RANK GENERATION,PRESERVATION, AND REVERSAL IN THE ANALYTIC HIERARCHY DECISION PROCESS

Decision making has the objective of finding the best alternative or set of alternatives by considering a number of goals, objectives, criteria, competitors, and other important factors. The analytic hierarchy process is a decision aid used to assist a decision maker in sorting out the complexity of a decision problem and making use of his or her judgments. A decision maker must be assured that the arithmetic operations of any such decision process are the right ones—that they surface the correct ranking and values of the alternatives and preserve or alter ranks appropriately when new alternatives are added or deleted. In this paper it will be shown that with absolute measurement, rank always is preserved, with relative measurement, rank changes with nspect to scveral criteria only because of the structural dependence (involving both numbers and measurements) of criteria on alternatives. A discussion of the effect on rank of replicas and near replicas of the alternatives also is given.     

AGGREGATING EXPERT OPINION IN DECISION-MAKING

In using nominal groups for decision making, it is necessary to use some mechanical procedure for combining the evaluations. A simulation model is used to compare procedures for the case where a nominal group of m evaluators must select the best of n alternatives and where the evaluations are subject to random errors. Criteria are the probability of making a correct selection and the relative quality of the choice.     

Sequential Search and Selection Problem Under Uncertainty

This paper formulates and discusses a series of sequential decision problems of the following common structure: A decision alternative of multiple attributes‐that is, a job, an employee, or an investment alternative‐is to be selected within a certain fixed length of time. An unknown number of alternatives are presented sequentially, either deterministically or in a random manner. The decision maker can rank all the alternatives from best to worst without ties, and the decision to accept or reject an alternative is based solely on the relative ranks of those alternatives evaluated so far. The nonparametric sequential decision problem is first studied for a model involving a discrete time period and then generalized in terms of continuous time. Also considered is a variant of this problem involving a Bayesian estimation of (1) the uncertain probability of having an alternative at a given stage in the discrete‐time model and (2) the arrival rate of alternatives in the continuous‐time model. The optimal selection strategy that maximizes the probability of selecting the absolute best alternative is illustrated with the job search problem and the single‐machine job assignment problem.     

Missing consequences in multiattribute utility theory

This paper addresses how to deal with decision alternatives with missing consequences in multicriteria decision-making problems. We propose disregarding the attributes for which a decision alternative provides no consequence by redistributing their respective weights throughout the objective hierarchy in favor of a straightforward idea: the assignation of the respective attribute range as a default value for missing consequences due to possible uncertainty about the decision alternative consequences. In both cases, decision alternatives are evaluated by means of an additive multi-attribute utility model. An illustrative example of the restoration of radionuclide contaminated aquatic ecosystems is shown.     

A deterministic model for the housing decision

The decision to rent or buy housing, or to choose among various housing acquisition alternatives, represents an important and complex financial problem, which confronts virtually all individuals. This paper develops a comprehensive model (within the institutional and legislative context of the United States) which provides theoretically appropriate criteria for evaluating personal housing alternatives. Empirical results clearly indicate the economic consequences of housing alternatives, and both substantiate some and contradict other “wisdoms” concerning the housing decision.     

对方案有偏好的不确定语言多属性决策方法

研究了属性权重完全未知、属性值和对方案的偏好值以不确定语言变量形式给出的不确定语言多属性决策问题。首先,引入不确定语言变量的运算法则,以及不确定语言变量之间比较的可能度公式,给出了不确定语言变量间的距离的概念。针对属性权重完全未知的情形,给出了求解权重的公式。然后,利用不确定语言加权平均算子,对不确定语言决策信息进行加权集成,并利用可能度公式构造可能度矩阵(互补判断矩阵),继而利用互补判断矩阵排序公式对决策方案进行排序和择优。最后进行了实例分析。     

Intelligence gathering for decision making

Empirical studies of decision making seldom consider the intelligence gathering activities required for decision making. In an attempt to fill this void, this study set out to identify and assess some of the key steps in gathering intelligence, considering the difficulty of the decision and available resources. The study found performance gapping and premising to be crucial activities and explored how each is carried out. A variety of premising and gapping tactics were uncovered, with some having better success than others. These tactics were found to influence the search approach selected to uncover alternatives and the success of the resulting decision. The best results were noted when search efforts are guided by needs documented with a quantitative performance gap; and when formal search or negotiation is used to identify alternatives. These findings hold for decisions that have high and low difficulty and for those with high and low resource support. The implications of these findings for decision makers and decision making are discussed.     

一种基于偏好分布的群决策方法

为了满足群决策的实际需求,本文提出了一种基于偏好分布的群决策方法,该方法利用完全不对称预先排序向量表示决策者的偏好,通过分析计算偏好排序向量的密度和分布结构,从可行方案集合中寻找所有决策者都能接受的优选方案集合,逐次缩小搜索空间以逼近一致满意解。该方法结合冲突分析,可进一步分析决策者之间的相互关系,集成于谈判支持系统,具有直观、实用等特点,最后给出了一个实际例子说明该方法。     

考虑决策者损失规避的异质信息多属性变权决策方法

现实中存在大量异质信息（或数据）和需要考虑权重随属性值变化的多属性决策问题。针对这类异质信息多属性决策问题，本文提出了一种基于前景理论的变权综合求解方法。首先，构建了异质信息的统一距离计算公式，进而计算各个决策方案的相对贴近度；然后，提出基于不同类型效用函数的变权向量构造方法；其次，以初始权重为参考点，计算变权向量相对于参考点的益损决策矩阵，进而计算考虑决策者权重损失和收益的风险态度的各个决策方案的前景综合值，据此确定方案优劣排序和最优方案。通过数值例子的计算分析说明，文中所提决策模型与方法具有较好的有效性和合理性，可为解决复杂情景的决策问题提供理论依据与方法支持。     

Von der Kunst, sich für den richtigen Beruf zu entscheiden

Students often make their decision of a course of studies without being aware of the consequences for their future career and life, without having been informed about alternatives and — even more important — without having thought about their personal talents and interests. During their studies itself, they often run into difficulties when they realise that they took the wrong decision. High rates of changes in studies or cancelling all studies are the consequence (25 % in total, more than 40 % in special studies like social sciences). The author works as a students’ advisor and students’ coach and, among others, offers analyses of talents and a comprehensive advisory training for professional orientation. The present essay describes the theoretical basis of her work, the concrete procedure and a practical example of her daily work.     

The inferring of preferences from indifferences in multicriteria decision analysis

Rivett [5] has proposed that an approximate preference ordering may be deduced from statements of pairwise indifferences between decision alternatives by using multi-dimensional scaling. In this paper it is demonstrated that much stronger evaluations of preference are possible by applying formal statistical inferential procedures to a simple parametric model, relating indifference to closeness on a scale defined by a linear function of attribute values. This can be used to screen out a considerable proportion of less desirable decision alternatives. The method is illustrated by application to Rivett's problem of the hypothetical Town of Brove, for which a satisfactory matching with Rivett's utilities is obtained. It is also shown that the method can provide useful preference orderings on the basis of less than 20% of all possible pairwise comparisons between alternatives.