Letter grades have now almost vanished, but the problem of how to mark excellent work has not. As there is a general push towards using the upper part of the marking scale, it is important to look at the consequences of awarding very high marks. This paper considers the undergraduate classification rules, but similar problems exist for postgraduate taught courses. This means that first-class marks, when averaged into a mean, can have a dramatic effect on final classification. For a given assessment unit, the difference between getting a bare first and a very good first is the same as the difference between a poor third and a good upper-second.
Some examiners are clearly uncertain about how to use the wide top range.
So marks in the 70s and 80s are for work that is excellent but not outstanding - a nice distinction. Different kinds of work imply different styles of marking. Different areas use marks differently. These inconsistencies affect COGS in particular. The BA programme in AI shares courses with various BSc programmes.