An empirical study of the correlations between function point elements [software metrics]

Researchers and practitioners have noted correlations between the five types of elements in function point analysis. Practitioners exploit them; researchers have raised concerns about them. Two previous studies of the correlations between the elements have agreed in some findings, but differed on others. A large data set is analyzed here to gain further insight into the correlations. Two elements (inputs and logical files) are found to be correlated always, and one element (external files) is found to be generally uncorrelated with the others. Correlations are strongest in new development projects that use 4GLs. These results confirm some findings of previous researchers, and suggest explanations for differences between previous findings.