| _version_ | 1866901967138193408 |
|---|---|
| author | Gauk, Martin Eberhardt, Jan |
| author_facet | Gauk, Martin Eberhardt, Jan |
| contents | Most examinations at TU Berlin had to be conducted online due to the COVID-19 outbreak and lockdowns during the winter term 2020/21. Although most exams were designed to be open-book or non-collaborative take-home exams, it enabled students to commit fraud by collaborating. Therefore, we implemented a method in the Moodle LMS to detect copied answers by adding individual watermarks while the students type their answers. If a student were to copy their answer out of the textbox and share it with their classmates (e.g. via an instant messaging service) who then paste the answer into their own textboxes, the system would be able to recognize the watermarks and who copied from whom. The text watermarks are invisible (by using non-printing Unicode characters) and will not get lost while copying. The system is able to reliably detect fraud if students use the described approach. Even though the students were made aware of a fraud detection system, a very small percentage of cheaters were still able to be exposed by it. There is a possibility that many others cheated through other means (e.g. by sharing screenshots) that are hard or impossible to be detected. The collaborations that were detected took place only in exams that consisted of no or a very small number of random questions. Accordingly, building a large question bank is one of the most effective ways to stop students from easily collaborating during an exam. |
| format | Recurso digital |
| id | zenodo_https___doi_org_10_5281_zenodo_14650294 |
| institution | Zenodo |
| language | eng |
| publishDate | 2021 |
| publisher | Zenodo |
| record_format | zenodo |
| spellingShingle | Fraud Detection Using Watermarks in Examination Answers Gauk, Martin Eberhardt, Jan remote examination watermarking fraud detection Most examinations at TU Berlin had to be conducted online due to the COVID-19 outbreak and lockdowns during the winter term 2020/21. Although most exams were designed to be open-book or non-collaborative take-home exams, it enabled students to commit fraud by collaborating. Therefore, we implemented a method in the Moodle LMS to detect copied answers by adding individual watermarks while the students type their answers. If a student were to copy their answer out of the textbox and share it with their classmates (e.g. via an instant messaging service) who then paste the answer into their own textboxes, the system would be able to recognize the watermarks and who copied from whom. The text watermarks are invisible (by using non-printing Unicode characters) and will not get lost while copying. The system is able to reliably detect fraud if students use the described approach. Even though the students were made aware of a fraud detection system, a very small percentage of cheaters were still able to be exposed by it. There is a possibility that many others cheated through other means (e.g. by sharing screenshots) that are hard or impossible to be detected. The collaborations that were detected took place only in exams that consisted of no or a very small number of random questions. Accordingly, building a large question bank is one of the most effective ways to stop students from easily collaborating during an exam. |
| title | Fraud Detection Using Watermarks in Examination Answers |
| topic | remote examination watermarking fraud detection |
| url | https://doi.org/10.5281/zenodo.14650294 |