Abstract: Most automatic scoring systems use pattern based that requires a lot of hard and tedious work. These systems work in a supervised manner where predefined patterns and scoring rules are generated. This paper presents a different unsupervised approach which deals with students’ answers holistically using text to text similarity. Different String-based and Corpus-based similarity measures were tested separately and then combined to achieve a maximum correlation value of 0.504. The achieved correlation is the best value achieved for unsupervised approach Bag of Words (BOW) when compared to previous work.

Wael H Gomaa and Aly A. Fahmy, “Short Answer Grading Using String Similarity And Corpus-Based Similarity” International Journal of Advanced Computer Science and Applications(IJACSA), 3(11), 2012. http://dx.doi.org/10.14569/IJACSA.2012.031119

@article{Gomaa2012,
title = {Short Answer Grading Using String Similarity And Corpus-Based Similarity},
journal = {International Journal of Advanced Computer Science and Applications},
doi = {10.14569/IJACSA.2012.031119},
url = {http://dx.doi.org/10.14569/IJACSA.2012.031119},
year = {2012},
publisher = {The Science and Information Organization},
volume = {3},
number = {11},
author = {Wael H Gomaa and Aly A. Fahmy}
}