A rule-based approach for estimating software development cost using function point and goal and scenario based requirements

Function point is a method used to measure software size and estimate the development cost. However, for large complex systems, cost estimation is difficult because of the large number of requirements expressed in natural language. In this paper we propose a rule-based approach for estimating software development cost in the requirements analysis phase. It combines goal and scenario based requirements analysis with function point based cost estimation. In our proposed approach, Context Analysis Guiding rules, Data Function Extraction Guiding rules, and Transaction Function Extraction Guiding rules have been developed to identify function points from text based goal and scenario descriptions. These rules are established based on a linguistic approach. The contribution of the proposed approach is to help project managers decide which requirements should be realized.