Hix and Hartson: Developing User Interfaces: Chapter 5
by Carson Reynolds
An Overview of Systems Analysis and Design provides exactly that, a discussion of early analysis activities and design techniques. Systems analysis techniques are categorized:
- Need Analysis
- User Analysis
- Task Analysis
- Functional Analysis
- Task/Function Allocation
- Requirement Analysis
The above are shown as part of an interwoven process. The authors cite Holztblatt’s contextual inquiry technique as one method to make analysis more effective. They also suggest including a problem domain expert in the development team.
The next sections concern themselves with an exercise in the development of a Calendar Management System. Various aspects of Systems Analysis are gone over in more detail and with exercises to further familiarize readers.
Needs analysis is a tool to help determine what the systems under development should be. Actually, this is the formulation of a concise goal statement, along with some assumptions and feature descriptors.
User analysis involves interview and survey techniques where we collect characteristics like level of computer expertise, hardware and software they’re familiar with, education level, organization knowledge. Following this, the authors suggest another iteration of needs analysis, reformulation of the goals in light of a better understanding of the users.
Task analysis involves decomposing the main goal of the system into a hierarchy of tasks, recursively. This eventually decomposes into the resources necessary to perform the tasks.
Functional Analysis is defined as description of the system (non-interface) functions that need to be designed to support the task. Task/Function Allocation involves deciding which tasks are performed by the user (manual) and which by the system (automated). These activities need to be iterated as the systems develops.
Having finished the task analysis we are to turn our attention to the systems design. The authors divide design into conceptual (high level) and detailed (specifics). Conceptual is independent of appearance.
Designing an initial scenario is the next step in the author’s design process. The initial scenario is a visual design and layout for a few screens (a storyboard).
An early usability evaluation is suggested on the product of the initial scenario design. This can involve some cognitive walk throughs and user feedback. Iterations of the initial design will be suggested by the outcome of the evaluation.