This research evaluates the psychometric properties of short-answer response items under a variety of grading rules in the context of a mobile learning platform in Africa. This work has three main findings. First, we introduce the concept of a differential device function (DDF), a type of differential item function that stems from the device a…

Within this paper I report on aspects of a study aimed at not only discovering how and when students use a graphical calculator within an Advanced-Level (pre-University) Mathematics course, and what operations and calculations they perform with such calculators, but also the depth and type of learning that takes place when students use graphical…