In the context of marking examinations, double marking is a means to enhance reliability. However, deciding if it is worthwhile incorporates a dilemma. Intuitively, it increases the reliability of the assessment and shows fairness in marking, but it needs to be proven a benefit in order to justify the additional time and effort that it takes. One factor which affects the re-marking is whether or not the second marker is aware of the marks awarded by the first marker. Higher agreement is observed between two examiners when the second knows how, and perhaps why, the first marked an exam. This may suggest that the second examiner took advantage of the annotations available when trying to judge the best mark for a candidate. An alternative perspective may suggest that the second examiner was influenced by the first examiner's marks.

The purpose of this research is to evaluate the extent to which examiners agree when using different double marking models, in particular, blind and annotated double marking. The impact of examiner experience is also investigated.