Better Feedback for Educational Online Judges

Anaga Mani, Divya Venkataramani, Jordi Petit, Salvador Roura


The verdicts of most online programming judges are, essentially, binary: the submitted codes are either “good enough” or not. Whilst this policy is appropriate for competitive or recruitment platforms, it can hinder the adoption of online judges on educative settings, where it could be adequate to provide better feedback to a student (or instructor) that has submitted a wrong code. An obvious option would be to just show him or her an instance where the code fails. However, that particular instance could be not very significant, and so could induce unreflectively patching the code. The approach considered in this paper is to data mine all the past incorrect submissions by all the users of the judge, so to extract a small subset of private test cases that may be relevant to most future users. Our solution is based on parsing the test files, building a bipartite graph, and solving a Set Cover problem by means of Integer Linear Programming. We have tested our solution with a hundred problems in Those experiments suggest that our approach is general, efficient, and provides high quality results.


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Paper Citation

in Harvard Style

Mani A., Venkataramani D., Petit J. and Roura S. (2014). Better Feedback for Educational Online Judges . In Proceedings of the 6th International Conference on Computer Supported Education - Volume 2: CSEDU, ISBN 978-989-758-021-5, pages 176-183. DOI: 10.5220/0004842801760183

in Bibtex Style

author={Anaga Mani and Divya Venkataramani and Jordi Petit and Salvador Roura},
title={Better Feedback for Educational Online Judges},
booktitle={Proceedings of the 6th International Conference on Computer Supported Education - Volume 2: CSEDU,},

in EndNote Style

JO - Proceedings of the 6th International Conference on Computer Supported Education - Volume 2: CSEDU,
TI - Better Feedback for Educational Online Judges
SN - 978-989-758-021-5
AU - Mani A.
AU - Venkataramani D.
AU - Petit J.
AU - Roura S.
PY - 2014
SP - 176
EP - 183
DO - 10.5220/0004842801760183