An Integrated Quantitative Assessment Model For Usability Engineering

Many different quantitative assessment models have been proposed to measure and report the usability of a general software product for various business and design purposes. However, there are several problems coupled with existing models that consequently bias and affect the process and results of the usability assessment. Moreover, they do not aid their usage by analysts who are not experienced in the filed of usability. Therefore, an integrated, accurate, consolidated and simple usability assessment model is required, to provide an entire construct of usability for general software products. In this paper, we proposed an Integrated Quantitative Assessment Model for Usability Engineering (IQAMUE) for measuring and reporting usability for general software products. The contribution of the IQAMUE has been done at several points: (1) The investigation into existing models that represents usability factors, either by standard bodies or by well-known researches in the field of usability. As a result, we have proposed an improved comprehensive model, which integrates potential and general usability factors, and measure their related metrics in a standard way (2) We have proposed an adjustable sample size estimation model for usability assessment, which enhances the estimation process, by using historical data to gain an initial idea of the software product, and on present data to predict the complexity of the software product (3) For the applicability purpose of the proposed model, we have conducted an empirical case study for a local e-mail system (Eudora V7) to examine and practice the proposed model.