A Lean Approach to Estimate the Functional Size of Operating Applications

Functional size measures have been gaining increasing acceptance not only for project estimation and productivity comparisons but also for the evaluation of the company assets concerning with operating applications. However, functional sizing operating applications can represent a complex task (they could be developed in past projects, in some cases by others, with long standing technologies, and without useful documentation supporting them). Thus, companies require cheaper strategies to estimate functional size of these applications. To this end, we proposed some measurement approaches concerning with the number of physical tables and the number of read and read/written tables that can be easily collected from the database schema and the application interfaces. We assessed the effectiveness of the proposals performing an empirical study based on 17 applications of an Italian company. The results highlight that the proposed approaches allowed to obtain accurate functional size estimations, thus turning out to be suitable for the involved company.