An empirical analysis of function point adjustment factors

In function point analysis, fourteen "general systems characteristics" (GSCs) are used to construct a "value adjustment factor" (VAF), with which a basic function point count is adjusted. Although the GSCs and VAF have been criticized on both theoretical and practical grounds, they are used by many practitioners. This paper reports on an empirical investigation into their use and practical value. We conclude that recording the GSCs may be useful for understanding project cost drivers and for comparing similar projects, but the VAF should not be used: doubts about its construction are not balanced by any practical benefit. A new formulation is needed for using the GSCs to explain effort; factors identified here could guide further research. (C) 2000 Elsevier Science B.V. All rights reserved.