Using certainty-based marking

When a student answers a question they also have to state how sure they are of the answer: not very (less than 67%); fairly (more than 67%) or very (more than 80%). Their grading is then adjusted according to how certain they are, which means that for example if they answered correctly but were only guessing, their mark is adjusted from 1 to 0.33. If they answered wrongly but were very sure, their mark is adjusted from 0 to -2.

CBM in Moodle is based on strategies developed by Prof. Gardner-Medwin at UCL (London, UK) and there is a patch available for download which extends and enhances the default Moodle behaviour. It changes the feedback marks to 1,2,3. A 'No Idea' option is also implemented. Feedback with patches includes both accuracy and CBM scores, with breakdown of performance by C level.

The link to download the CBM patch, along with more detailed information and demonstration sites is available from http://www.tmedwin.net/cbm/moodle/index.htm