The Role of Components of Data Flow Diagram and Data Dictionary in Managing Software Size

摘要

Managing and planning good software is not an easy task, as software estimation activities are concerned not only with time and effort scheduling, but also with specifying work activities, skill levels and scheduling of necessary resources. With duration, effort and other factors overlooked, poor reliability and functionality of software may occur. Furthermore, inaccurate estimation will lead to higher pressure for working team, poor quality of final system development, and higher cost for developing software. Due to these reasons, a software size model was constructed using a sample consisting of 122 student projects. All the collected student projects addressed transaction processing, data retrieval and reporting, and file maintenance activities/They were developed following the phases of system development life cycle and up to the expectations of the clients, Variables considered for constructing the software size model are directly extracted from Data Flow Diagrams(DFDs) and Data Dictionaries(DDs). This model takes several advantages: (1) there tends to be fewer counting problems than other software metrics, because this model is based upon simple counts; (2) the predicted software projects were calibrated to specific local environments rather than being based upon industry weights; (3) basic size components can be identified easily at the early stage of the development life cycle; (4) the model provides clues to project designers in planning and scheduling the development of new software projects. Finally, our work shows that it is possible to develop simple and useful software predictions based on simple counts extracted from early stage of system development life cycle without recourse to complex analysis techniques. We conclude that our model can provide valuable ideas and supports for project designers in managing software activities.