A Quantitative Evaluation Method of Software Usability Based on Improved GOMS Model

Kunlong Wang, Kanjing Li, Jinhua Gao, Bing Liu, Zhi Fang, Wenjun Ke

Abstract: The Goal, Object, Model, and Selection Rules (GOMS) model plays an important role in user interface (UI) designs for evaluating the software usability. The vanilla GOMS has loosely defined the basic operators and their associated cost. In this paper, we propose an improved GOMS model to quantitatively estimate the software usability. Firstly, it emphasis that the complexity of mouse positioning is not a constant. It is affected by the size of the background area during positioning. Therefore, we introduce a novel complexity metric of mouse positioning. Then, based on GOMS, we put forward the concept of business operation complexity, which is used to evaluate the system usability by the sum of the operation complexity. Finally, we conduct a case study by applying our method to the software usability evaluation of Invoicing Systems, which demonstrates that our method is capable of giving reasonable advices for the UI designers