My grades are above average.
One way to resolve this apparent contradiction is to notice who the comparisons are between. In the experiments where people consider themselves above average, the comparisons are between strangers.
Six: He has above average willpower. Seven: He has determination and willingness to work hard.
Jan's work is above average; Hob's is very much below it.
They are above average 85 . I'm among the upper third of my class.
We might, for example, frame someone's performance as asto above average or good.