Automated Building of Domain Ontologies from Lecture Notes in Courseware

Courseware repositories contain large amounts of lecture videos and text. When searching for lecture material on a given topic, it would be useful if the repository also indicates the topics that are pre-requisites. In this paper we present a technique that automatically constructs the ontology (dependency graph) from the given lecture notes. We show how this ontology can be used to identify the pre-requisites and follow-up modules for a given query (lecture topic). We also provide the user with a dependency graph which gives a conceptual view of the domain. Our system extracts the concepts using term frequency inverse document frequency (tf-idf) weighting scheme and then determines the associations among concepts using apriori algorithm. We have evaluated our system by comparing its results with the dependencies determined by an expert in the subject area.