The Certainty assumption that is used in economic analysis, althouth is easier in analysis, may be but not logical because in most projects time is playing a key role. In this time horizon the amount of income and future costs affecting by factors that are not managable by investors and can not to be forecasted. Therefore in practice usually there is a gap between forecased and real variables. In risk and uncertainty condition the results of economic analysis could be altered by a few changes in uncertain parameter.
In this paper, the formulas for the analyses of fuzzy present value, fuzzy equivalent uniform annual value and fuzzy benefit–cost ratio are developed given some numeric examples. This paper one of the few researches which used a model for economic evaluation of projects with fuzzy logic.
JEL Classification: CO2, C61