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Specification and Validation of a Formative Index to Evaluate the Ergonomic Quality of an AR-based Educational Platform

The ergonomic quality of educational systems is a key feature influencing both the usefulness and motivation for the learner. Desktop Augmented Reality (AR) systems are featuring specific interaction techniques that may create additional usability issues affecting the perceived ease of use. Measuring key usability aspects and understanding the causal relationships between them is a challenge that requires formative measurement models specification and validation. In this paper we present an evaluation instrument based on two main formative indexes that are capturing specific usability measures for two AR-based applications. The formative indexes are forming a second order formative construct that acts as predictor for both the general ease of use and ease of learning how to operate with the application.