Pekka Salminen

Using multicriteria methods in environmental planning and management.

In environmental planning and decision processes several alternatives are analyzed in terms of multiple noncommensurate criteria, and many different stakeholders with conflicting preferences are involved. Based on our experience in real-life applications, we discuss how multicriteria decision aid (MCDA) methods can be used successfully in such processes. MCDA methods support these processes by providing a framework for collecting, storing, and processing all relevant information, thus making the decision process traceable and transparent. It is therefore possible to understand and explain why, under several conflicting preferences, a particular decision was made. The MCDA framework also makes the requirements for new information explicit, thus supporting the allocation of resources for the process.

SMAA - Stochastic multiobjective acceptability analysis

Stochastic multiobjective acceptability analysis (SMAA) is a multicriteria decision support technique for multiple decision makers based on exploring the weight space. Inaccurate or uncertain input data can be represented as probability distributions. In SMAA the decision makers need not express their preferences explicitly or implicitly; instead the technique analyses what kind of valuations would make each alternative the preferred one. The method produces for each alternative an acceptability index measuring the variety of different valuations that support that alternative, a central weight vector representing the typical valuations resulting in that decision, and a confidence factor measuring whether the input data is accurate enough for making an informed decision.

Choosing a solid waste management system using multicriteria decision analysis

Abstract We report on an actual application of the ELECTRE III decision-aid in the context of choosing a solid waste management system in the Oulu region, Finland, in 1993. The Electre III method proved useful, especially when dealing with environmental problems involving many decision-makers, and in cases where the outcomes of the various alternatives remain to some degree uncertain. One of the main conclusions of our study is that all the proper landfill capacity available in the planning region should be used up. In addition, the energy potential of waste should be utilized within the region. Therefore, the solution recommended for a solid waste management system was intermediate landfilling, composting and RFD-combustion. The decision-makers commented positively on the method used and were satisfied with the options recommended. The scheme will be implemented for use from the beginning of the year 1995.

Ordinal criteria in stochastic multicriteria acceptability analysis (SMAA)

Abstract We suggest a method for providing descriptive information about the acceptability of decision alternatives in discrete co-operative group decision-making problems. The new SMAA-O method is a variant of the stochastic multicriteria acceptability analysis (SMAA). SMAA-O is designed for problems where criteria information for some or all criteria is ordinal; that is, experts (or decision-makers) have ranked the alternatives according to each (ordinal) criterion. Considerable savings can be obtained if rank information for some or all the criteria is sufficient for making decisions without significant loss of quality. The approach is particularly useful for group decision making when the group can agree on the use of an additive decision model but only partial preference information, or none at all, is available.

A stochastic method for robustness analysis in sorting problems

ELECTRE TRI is a multiple criteria decision aiding sorting method with a history of successful real-life applications. In ELECTRE TRI, values for certain parameters have to be provided. We propose a new method, SMAA-TRI, that is based on stochastic multicriteria acceptability analysis (SMAA), for analyzing the stability of such parameters. The stability analysis can be used for deriving robust conclusions. SMAA-TRI allows ELECTRE TRI to be used with uncertain, arbitrarily distributed values for weights, the lambda cutting level, and profiles. The method consists of analyzing finite spaces of arbitrarily distributed parameter values. Monte Carlo simulation is applied in this in order to describe for each alternative the share of parameter values that have it assigned to different categories. We show the real-life applicability by re-analyzing a case study in the field of risk assessment.

A multiple criteria decision model for analyzing and choosing among different development patterns for the Helsinki cargo harbor

Abstract This paper describes a real application of a multicriteria approach to choosing among different options for developing the Helsinki harbor. In addition to the environmental impact assessment procedure, an analysis of the alternatives using the SMAA-method (Stochastic Multiobjective Acceptability Analysis) is carried out. The method applied here has been developed for situations in which the use of decision-makers’ preference information is not possible. Instead, the problem is described by typical weight vectors leading to each solution, taking into account the evident uncertainty embedded in the criteria values.

Determining the implementation order of a general plan by using a multicriteria method

We describe a real-life application of a new multicriteria method in the context of assisting the decision-making for a general plan in the municipality of Kirkkonummi in Uusimaa, Finland. At the time our group started working on the problem, a proposal for an overall plan had already been completed, but the order in which different regional parts of the plan should be implemented needed to be considered based on the environmental impact assessment (EIA) procedure. The EIA procedure generated a large amount of data about the different impacts of the alternatives. For this group decision making problem we developed the SMAA-3 decision support method which does not require any explicit preference information from the decision makers during the procedure. The uncertainty of the basic data is modelled using ELECTRE III-type pseudo-criteria with preference and indifference thresholds.

ELECTRE III and IV Decision Aids in an Environmental Problem

This paper gives a description and analysis of the use of ELECTRE III and IV decision aids in the context of choosing a solid waste management system in two different real applications in Finland. Both methods fit this context well in general, since the problem involves many criteria and many ‘decision makers’. The available data are imprecise, which also favours the use of outranking methods. In addition to the real applications, we also study the choice behaviour offered for decision makers in connection with these methods by looking at some test results obtained from randomly generated problems. In general, the results of ELECTRE III and IV do not differ substantially from those from the application of traditional value functions.

Decision-aid for discrete multiple criteria decision making problems with imprecise data

Abstract We describe ways of aiding decision making with a discrete set of alternatives. In many decision situations, it is not possible to obtain explicit preference information from the decision makers. Instead, useful decision-aid can be provided to the decision makers by describing what kind of weighting of the criteria result in certain choices of the alternatives. The suggested treatment is based on the basic ideas of the ELECTRE III method. The modelling of the preferences by pseudo-criteria is especially helpful in case the data, that is, the criterion values are imprecise. Unlike ELECTRE III, no ranking of the alternatives is produced. Based on a minimum-procedure in the exploitation of the outranking relations, we provide information about the weights of the criteria that make a certain alternative the best. We also present an interactive searching procedure in the weighting space. The auxiliary optimization problems to be solved are nondifferentiable. Cases with both single and multiple decision makers are considered.

The Choice of a Solid Waste Management System Using the Electre Ii Decision-Aid Method

A multicriteria decision-aid method, Electre II, was applied to the real choice process of a solid waste management system in the Uusimaa region, Finland. The criteria used were chosen by a supervision group. The weights of the criteria were defined by the managers of environmental and technical affairs of each municipality in Uusimaa, Finland. The use of the Electre II method leads us to recommend centralized incineration as the best municipal solid waste management system for the planning region. However, the second best alternative, intermediate RDF combustion with intermediate landfilling was finally chosen by the municipalities.