Do Different Functionality Types Affect the Relationship between Software Functional Size and Effort

Effort estimation is a significant practical problem in software engineering, and various cost drivers, including software size, which might have an impact on it have been explored. In many of these studies, total software size (measured in either lines of code or functional size units) is the primary input. However, the relationship between effort and the components of functional size has not yet been fully analyzed. This study explores whether effort estimation models based on the functional size components, that is, Base Functional Component types, rather than those based on a single total value, would improve estimation models. For this empirical study, the project data in the International Software Benchmarking Standards Group (ISBSG) Release 10 dataset, which were sized by the COSMIC FFP method, are used.