Thanks Pwar and andy for your responses. I received this email from the convenor:
In regard to the mark of 63, I reiterate what I wrote to you on December 20, 2010 when you first contacted me to enquire informally about your grade. A SNG is “a ranking within a letter grade. In your case, the SNG places you near the top level of a "Pass" grade. In regard to this mark, you must remember that it is common practice for raw marks to be scaled in arriving at SNGs, and that grading is qualitative as well as quantitative, and based on all of the available evidence.” In LING214, 75% of the final mark is based on performance in the major report (for which you scored 53%) and the exam (for which you scored 58%). These marks, taken in combination with your critique and experimental participation marks, and your overall performance relative to other students in the unit, placed you at the top of the Pass grade: Hence, the mark of 63.
Overall, I got
5/5.
16/30.
18/20
26/45.
So, that's 65.