A computational method of complexity of questions on contents of English sentences and its evaluation

This paper describes a computational method of complexity of a question for an adaptive question and answer function in an intelligent support system for English learning, and its evaluation. To realize adaptive question and answer, systems should generate questions depending on both educational intentions and learner's understanding state. For generating suitable questions for a learner automatically, systems must know the factors which influence difficulty of questions, and have the ability to calculate difficulty. Difficulty is composed of a learner dependent part and an independent part. The former is evaluated by referring to a student model. The latter is defined by enumerating factors which influence complexity of questions. We present a definition of complexity of questions along learners' answering process. We also describe experimentation of comparing the complexity of questions calculated by computer with the complexity evaluated by human.