Empirical evaluation of an early understandability measurement method

Usability is a quality factor which increasingly attracts the attention of Human Computer Interaction (HCI) developers. It consists on measuring the usability aspects of a user interface and identifying specific problems. It was usually evaluated based on user's perception. The development costs are the main limitation of methods which target the usability measurement. However, the appearance of the Model Driven Engineering (MDE) allows migrating to a new challenge: early usability evaluation. In an MDE method, the conceptual model represents an abstraction of the application code. Hence, measuring the usability since the conceptual model can be a promising method to predict the usability of the application code. This paper proposes that certain usability attributes, especially understandability attributes, can be measured from the conceptual model. An empirical study is carried out in order to evaluate our proposal. The goal is to evaluate the coherence between values obtained using our proposal and those perceived by the end user.