In recent years, quantitative multicriteria methods have been widely used for comparative evaluation of complicated technological and social-economic processes, as well as for determining the best alternative among the available options and ranking the al

Abstract

In recent years, quantitative multicriteria methodshave been widely used for comparative evaluation ofcomplicated technological and social-economic processes,as well as for determining the best alternative among theavailable options and ranking the alternatives based ontheir significance for a particular purpose. Professor ofVilnius Gediminas Technical University E.K. Zavadskaswas the first to use these methods in Lithuania in the mideightiesof the last century for evaluation, substantiationand choosing of optimal technological solutions at variousstages of construction (Завадскас 1987). In this period,new multicriteria evaluation methods were beingdeveloped and widely used in the world in variousscientific and practical areas. Later, numerous disciplesand colleagues of prof. Zavadskas as well representativesof various scientific schools extensively used theconsidered methods in Lithuania.The main concept behind the quantitative evaluationmethods is integration of the values of the criteriadescribing a particular process and their weights(significances) into a single magnitude, i.e. the criterion ofthe method. For some particular (maximizing) criteria thelargest value is the best, while for others (minimizingcriteria) the smallest value is the best. The units of criteriameasurement are also different. The alternatives comparedare ranked according to the calculated values of thecriterion of the method. Great numbers of multicriteriaevaluation methods, based on different logical principlesand having different complexity levels and the inherentfeatures, have been created in the world. There is hardlyany ‘best’ multicriteria evaluation method. Therefore, aparallel use of several multicriteria evaluation methods aswell as the analysis of the spread of estimates andaveraging of the values obtained may be recommended forevaluating complicated multifaceted objects and processes.The method SAW (Simple Additive Weighting) is oneof the simplest, natural and most widely used multicriteriaevaluation methods. It clearly demonstrates the idea ofintegrating the values and weights of criteria into a singleestimating value – the criterion of the method. However,SAW uses only maximizing evaluation criteria, whileminimizing evaluation criteria should be converted into themaximizing ones by the respective formulas prior to theirapplication. This limitation is eliminated in the methodCOPRAS (Complex Proportional Assessment). The authorsof the method, E.K. Zavadskas and his discipleA.Kaklauskas suggested that the influence of maximizingand minimizing evaluation criteria should be assessedseparately. In this case, the component, taking into accountthe effect of maximizing criteria, matches the estimateyielded by the method SAW.Despite the fact that the method COPRAS is mostcommonly used in Lithuania, its main characteristics andproperties have not been clearly defined and demonstrated.However, the awareness of these properties allows us toshow the benefits of the method’s application, to predictthe influence of minimizing criteria values on the finalresult (estimate), to check the calculations and to take intoaccount possible instability of estimates yielded by themethod due to the specific character of the actual data.The paper describes the main features of multicriteriaevaluation methods SAW and COPRAS and their commonand diverse characteristics, as well as defining anddemonstrating the properties of the method COPRAS,which are of great theoretical and practical value.All theoretical statements are illustrated by numerousexamples and calculations.