Computer-Assisted Learning of Japanese as Second Language Based on a Dialog Text Database with Situated and Functional Indices as well as on a Diagnostic Parser

点击翻译按钮获取中文摘要

The research aims at fusion of grammatical and communicative approaches developing an intelligent assistance system for the learners of Japanese as second language. The system provides the learners with a text database with indices of learning items designating discriminatory use of expressions. Assisting the learners in comprehension of the contexts by way of linking with electronic dictionaries, the system asks the learners to fill in the blanks made in the sample texts by composing sentences selecting from the specified vocabulary and inflecting if necessary. The system diagnoses the composition and, if the erroneous sentences are not far from feasible ones, the system retrieves corresponding sample texts by the learning item indices, presenting them to help the learners recognize their errors by themselves.We developed a diagnostic parsing algorithm making use of Lexcalized Tree Adjoining Grammar and 2 stacks which proceeds by unification and linear back tracking. Provided the word … More list and the semantic modification relationship are shared with the learners, the algorithm successfully could detect excessive modifications, lacking of modifiers missing or missuse of collectives, erroneous inflections, obstacles against modification, crossed modification and inappropriateness viewed from the situations. In order to help the authors index the sample text, we developed a set of rules for mapping from the surface characteristics of the sample sentences to learning items. Use of only the morpheme patterns resulted in 90% of reproducibility and 84% of precision.Use of syntactic analysis focusing only single stages of modification resulted in 96% of reproducibility and 80% of precision. This lowering of precision may have been avoided by taking into account multiple morpheme candidates, 2 or more stages of modification and by prohibiting partial matching. It was confirmed that introduction of conceptual dictionary would greatly improve precision provided certain level of word sense disambiguation were achieved. Less