Building an Intelligent PAL from the Tutor.com Session Database- Phase 1: Data Mining

In this poster, we describe a new research project involving the analysis of nearly 250,000 human-human tutorial dialogue transcripts (in Algebra and Physics) supplied by Tutor.com, a leading provider of online tutorial services for children and young adults. This project involves training a panel of Subject Matter Experts (SMEs) recruited from among Tutor.com’s expert tutors to hand-tag a “gold standard ” training set of as many as 1,500 transcripts, involving hundreds of different tutors, and potentially totaling more than 100,000 separate utterances. The SMEs will use a theory-based coding scheme to classify utterances into dialogue acts and mode switches, i.e., dialogue acts that serve to initiate a change in dialogue mode. The resulting training set will be used to train a dialogue act classifier to automatically tag dialogue acts and modes in the remaining transcripts. Machine learning techniques will be used to discover patterns (e.g., sequences, clusters, Markov chains) associated with successful and less successful sessions, where success is measured by internal evidence of learning and also the learner and tutor ratings available in the transcript metadata. Due to the large number of sessions and tutors studied, this research promises to expand our understanding of the prevalence and types of strategies and tactics used by human tutors. Preliminary findings from this data set will be presented during the poster session.