On the relevance and learner dependence of co-text complexity for exercise difficulty

Abstract

Adaptive exercise sequencing in Intelligent Language Tutoring Systems (ILTS) aims to select exercises for individual learners that match their abilities. For exercises practicing forms in isolation, it may be sufficient for sequencing to consider the form being practiced. But when exercises embed the forms in a sentence or bigger language context, little is known about how the nature of this co-text influences learners in completing the exercises. To fill the gap, based on data from two large field studies conducted with an English ILTS in German secondary schools, we analyze the impact of co-text complexity on learner performance for different exercise types and learners at different proficiency levels. The results show that co-text complexity is an important predictor for a learner’s performance on practice exercises, especially for gap filling and Jumbled Sentences exercises, and particularly for learners at higher proficiency levels.