[ABSTRACT] A Study of the Correlation between Functional Size Measures and Object-oriented Measures

Lavazza & L. Geng

Background. Functional size measurement methods aim at measuring the size of functional user requirements of software applications. Functional user requirements can be represented via different notations, including UML diagrams. Objectives. In this paper, the relationship between functional size measures (namely IFPUG Function Points and COSMIC function points) and object-oriented measures of UML diagrams representing functional requirements are investigated. Method. A set of functional requirement specifications was modeled via UML diagrams.

The functional size measures of user requirements were derived via the standard IFPUG and COSMIC processes; the corresponding UML models were measured using object-oriented metrics. Functional size measures were then compared to object-oriented measures. Results. Statistically significant linear regression models were found, showing that functional size measures and object-oriented measures are correlated. Conclusions. The existence of the aforementioned correlations suggests that object-oriented measures –which tools can automatically extract from UML models– are substantially equivalent to functional size measures