Automated marking for interactive exercises on heuristic search algorithms

In this paper, we present an automatic marking system for marking interactive exercises related to heuristic search algorithms. It aims to assist tutors in assessing the performance of students and reduce the workload associated with their marking task. Also, it provides individualized and immediate feedback to the students. Automatic marking is achieved in two stages. First, the system compares a student´s answer with the correct one, using the `edit distance´ metric, and identifies the type of the answer, based on its completeness and accuracy as well as taking into account carelessness or inattention of the student. Second, it automatically marks the answer based on the answer´s type and the edit distance value. The system has been evaluated on a number of interactive exercises and its performance has been compared against that of an expert tutor. The experimental results are quite promising.