Additive aggregation with variable interdependent parameters: the VIP analysis software

Abstract

We consider the aggregation of multicriteria performances by means of an additive value function under imprecise information. The problem addressed here is the way an analysis may be conducted when the decision makers are not able to (or do not wish to) fix precise values for the importance parameters. These parameters can be seen as interdependent variables that may take several values subject to constraints. First, we briefly classify some existing approaches to deal with this problem. We will argue that they complement each other, each one having its merits and shortcomings. Then, we present a new decision support software-VIP Analysis-which incorporates approaches belonging to different classes. It proposes a methodology of analysis based on the progressive reduction of the number of alternatives, introducing a concept of tolerance that lets the decision makers use some of the approaches in a more flexible manner.

Simple procedures of choice in multicriteria problems without precise information about the alternatives’ values

“…In the context of MAVT this class of methods includes UTA [22], MACBETH [3], and GRIP [17]. Rather than inferring precise parameter values, VIP Analysis [13] can use ordinal information to infer constraints on MAVT weights, and then finds the set of conclusions that is compatible with these constraints (robust conclusions). The SMAA method [24] takes the opposite perspective by finding parameter values compatible with potential results, making it possible to find out what parameter values make an alternative the best one.…”

“…But in many cases this assumption is unrealistic, or there may even be advantages in working with less precise information. There are several reasons why a decision maker might prefer to provide incomplete information [12,13,25,46]: the decision might need to be taken under pressure of time and lack of data; the decision maker might not feel confident in providing precise figures for intangible or non-monetary parameters (e.g., parameters reflecting environmental impacts); the decision maker might have limited scope to process information; the decision maker might not want to reveal his preferences in public or might not want to state his preferences (as they could change during the process); the evaluation of the alternatives in some criteria might result from inaccurate statistics or measurements; the decision maker might consider it difficult to translate qualitative judgments into precise numerical values; the performance of some alternatives might depend on variables whose value is not known at the time of analysis; the information that would set the value of some parameters might be incomplete, not credible, contradictory or controversial. Some of these factors could be mitigated at the expense of time, discussions or money, but the decision maker may want to avoid incurring in these costs.…”

“…Most of the proposed methods deal with imprecision in terms of weights, considering the value of each alternative in each criterion is precisely known (e.g. [2,13,20,40,42,46]). There are also methods that address imprecision in performance values (e.g.…”

“…Rather than using a rule to identify a single alternative, our aim is to test how the rules behave in a strategy whereby the number of alternatives is progressively reduced [13]. Our aim is to test rules as screening procedures that identify a subset of promising alternatives in an effort to reconcile the contradictory objectives of maintaining a minimum number of alternatives while ensuring that the chosen subset contains the best alternative.…”

Modelo multicritério de decisão para localização de nova jaguaribara com vip analysis

“…O programa VIP Analysis (Dias & Clímaco, 2000a), pode ser encontrado no endereço: http://www4.fe.uc.pt/lmcdias/software.htm. Dias & Clímaco (2005) acentuam que esta ferramenta tem como objetivo apoiar a avaliação de um conjunto de alternativas de forma a escolher a mais preferida, de acordo com a função aditiva, conforme segue, sendo v j (a i ), o valor de a i para o critério j.…”