Predicting Understandability of a Software Project Using COCOMO II Model Drivers

This paper presents the results of an empirical study undertaken to investigate the utility of COCOMO II model drivers in predicting the understandability of a software project. Understandability is defined as the degree of clarity of the purpose and requirements of a software system to the developers of that system at the end of the Inception phase. COCOMO II scale factors and cost drivers relevant for prediction are shortlisted and a weightedsum formula relating these model drivers to understandability is derived through voting. The utility of this formula is judged by examining the COCOMO II model drivers of 24 real-client, MS-student, team projects done at USC. It is found that the weighted-sum formula correctly predicts the understandability of a software project in more than 80% of the cases suggesting a strong relationship between the shortlisted COCOMO II model drivers and the understandability of a software project. This objective way of measuring the understandability of a software project can be extremely useful in determining the time when it is safe to minimize the effort spent on requirements engineering activities.