Using Simulation to Aid Decision Making in Managing the Usability Evaluation Process

Context: This paper is developed in the context of Usability Engineering. More specifically, it focuses on the use of modelling and simulation to help decision-making in the scope of usability evaluation. Objective: The main goal of this paper is to present UESim: a System Dynamics simulation model to help decision-making in the make-up of the usability evaluation team during the process of usability evaluation. Method: To develop this research we followed four main research phases: a) study identification, b) study development, c) running and observation and finally, d) reflexion. In relation with these phases the paper describes the literature revision, the model building and validation, the model simulation and its results and finally the reflexion on it. Results: We developed and validated a model to simulate the usability evaluation process. Through three different simulations we analysed the effects of different compositions of the evaluation team on the outcome of the evaluation. The simulation results show the utility of the model in the decision making of the usability evaluation process by changing the number and expertise of evaluators employed. Conclusion: One of the main advantages of using such a simulation model is that it allows developers to observe the evolution of the key indicators of the evaluation process over time. UESim represents a customisable tool to help decision-making in the management of the usability evaluation process, since it makes it possible to analyse how the key process indicators are affected by the main management options of the Usability Evaluation Process

Model-based Simulation of Web Applications for Usability Assessment

In this paper we discuss an approach for simulating the behaviour of interactive software systems, before starting on any of the actual implementation, based on a model of the system at the architectural level. By providing a mock-up of the final user interface for controlling the simulation, it is possible to carry out usability assessments of the system much earlier in the design process than is usually the case. This means that design changes informed by this usability assessment can be made at this early stage. This is much less expensive than having to wait until an implementation of the system is completed before discovering flaws and having to make major changes to already implemented components. The approach is supported by a suite of cooperating tools for specification, formal modelling and animation of the system. 1