Using Edit Distance Algorithms to Compare Alternative Approaches to ITS Authoring

Abstract

One of the traditional goals of an Intelligent Tutoring System is to provide domain content for learners that is appropriate to their needs. A key component of this knowledge is the sequence in which instructional activities are performed and so unsurprisingly this is often a key task in ITS authoring. In order to understand this process better it is important to have accurate quantitative ways of classifying the difference between alternative sequences of ITS material. Edit distance algorithms provide a useful way of capturing this knowledge but suggest that weights need to be careful adjusted to capture important aspects of ITS sequences. The weighted algorithm is illustrated with examples from three studies using the REDEEM ITS authoring tool. This technique has allowed us to compare authors’ sequences in a way that is robust, quantifiable and that provides insights into ITS authors’ pedagogical principles.