Yourdon developed his own version of structured analysis that he named, the Yourdon Structured Method (YSM)™. Yourdon’s method is defined by three distinct steps: feasibility study, essential modeling, and implementation modeling (O 'Regan). The feasibility study is a conduction of an investigation in order to determine the goals of the project. By determining the goals, one can decide whether or not it makes sense to carry out the project. Important questions to consider are whether the project can be financially funded, whether it is organizational, whether it is ethical, and whether it is technically possible. It is important to document the data requirements of the system being designed. Following the feasibility study, essential modeling is carried out. This is where the actual process of identifying and modeling how the data moves about the system occurs. Finally, implementation modeling puts the plan into action and documents events that affect the data for improvement later …show more content…
It used data flow diagrams to represent user requirements and a technique known as functional decomposition to update and refine the method. The data flow diagram describes how data flows between sources, data processing, and storage. Individual elements that are placed in data flow diagrams are described further in the data dictionary (Bansler and Bodker). With the use of these two elements, a common language is provided and the communication gap between users and designers is bridged. When users needed assistance in using the method, Yourdon Inc. offered courses and consulting based off of functional decomposition (Bowles). However, since its introduction, YSM has been refined and modified several times. Yourdon Inc. ultimately did away with functional decomposition and replaced it with a technique known as event partitioning. With this new technique, the analysis process became much more guided and rigorous. Many reported that it changed the way that they looked at analysis (Bowles). Another change made to the Yourdon view of structured analysis significantly impacted Yourdon Inc. and their clients. The basic notations of the YSM were maintained, however the methods for deriving them were adapted to simplify the transition from analysis to design (Bowles). By doing so, the method could accurately keep up with the demands of the system in all types of development