Conversion of Function Points between NESMA and IFPUG method

FSM has proven to be a reliable method for organizations to estimate software and to compare productivity. But the concepts and estimating procedures of FSM methods are often too complex, detailed requirement and much training for staff is needed when estimating a project. A relative simple and accurate FPA (Function Point Analysis) method which can be applied early in the system life cycle will be very meaningful to organizations. The indicative function point count in NESMA, which is well known as “the Dutch Method”, is a simplified function point method. The Dutch method does not require a detailed specification which is fit for early estimation of the project, but the estimate result is usually inaccurate; IFPUG method provides more accurate results while it follows a complete counting procedure. This paper adopts unary linear regression analysis method to analyze datasets which were gathered from different organizations and gives a conversion model between Dutch method and IFPUG. The model is validated by using software projects measurements in both estimation methods, and the result is very close to IFPUG.