Extended Named Entity Recognition API and Its Applications in Language Education

We present an Extended Named Entity Recognition API to recognize various types of entities and classify the entities into 200 different categories. Each entity is classified into a hierarchy of entity categories, in which the categories near the root are more general than the categories near the leaves of the hierarchy. This category information can be used in various applications such as language educational applications, online news services and recommendation engines. We show an application of the API in a Japanese online news service for Japanese language learners.