ABSTRACT Accurate estimation of software development effort is critical in software engineering. The primary reason for cost estimation is to enable the client or the developer to perform a cost benefit analysis. The basic input for the cost models is size. In this paper we proposed a model on Takagi-Sugeno Fuzzy Logic for software cost estimation using fuzzy operator. The input is fuzzified by using two positive Triangular membership functions. Interval type-2 fuzzy logic and fuzzy operators are used to determine the firing intervals. The model deals efficiently with imprecise and uncertain input and enhances the reliability of software cost estimation. The estimated effort is optimized using the developed model and tested on NASA software projects on the basis of three criterions for assessment of software cost estimation models. A comparison of the all models is done and it is found that the developed models provide better estimation.
