A critical analysis of a hierarchy based Usability Model

For any software, its evaluation is significant for managing, controlling so that we can improve a software development process. For such evaluation of software, many factors have been recognized in literature surveys. Quality is one of most important factor which cannot be measured easily, because of its dependency on various other factors. Usability is such important factor on which quality of software depends. But as far as real world is concerned, we face a major obstacle in implementation of any usability model because there is a lack in precise definition and concept of globally accepted usability. Literature tends to define usability in overly brief and with ambiguous terms and describe its application in informal terms. Many software Usability Models which has developed so far, do not include all usability aspects and it is difficult to integrate these model into current software engineering practices. This paper aims to define and explain the term `usability´ using proposed detailed taxonomy. This paper also presents a critical analysis and evaluation of hierarchy based usability of software systems. Our proposed hierarchy based usability model presents 7 major attributes and 23 sub-attributes and these sub-attributes are further decomposed into 42 characteristics which collectively test the usability of a software product.