A Comparison of Length , Complexity and Functionality as Size Measures for Predicting Web Design and Authoring Effort

Software practitioners recognise the importance of realistic estimates of effort to the successful management of software projects, the Web being no exception. Estimates are necessary throughout the whole development life cycle. They are fundamental when bidding for a contract or when determining a project’s feasibility in terms of cost-benefit analysis. In addition, they allow project managers and development organisations to manage resources effectively. Size, which can be described in terms of length, functionality and complexity, is often a major determinant of effort. Most effort prediction models to date concentrate on functional measures of size, although length and complexity are also essential aspects of size. The first half of this paper describes a case study evaluation in which size metrics characterising length, complexity and functionality were obtained and used to generate effort prediction models for Web authoring and design. The second half describes the comparison of those size metrics as effort predictors by generating corresponding prediction models and comparing their accuracy using boxplots of the residuals. Results suggest that in general all categories presented a similar prediction accuracy.