Originally Posted by
Turb
It's not true that half of all pilots will be below average because that assumes a normal bell curve of competence where competence is plotted on the x axis. In practice I suspect the curve is an "S" with more pilots above the average which is dragged down by the worst pilots on the left hand side of the curve.
There was a similar debate on an earlier thread.
The conclusion was that competence vs frequency is indeed more-or-less a bell curve (i.e. tending towards zero frequency at both extremes), though possibly skewed a bit in the middle. That's only common sense - there will be (hopefully) very, very few pilots at the absolute minimum level of competence and a similarly small number at the upper extreme, with the numbers rising towards the mean/median.
You would only get an S-curve (or reverse S) if you plotted a cumulative frequency distribution i.e. competence vs the number of pilots who achieved (or failed to achieve) a given level of competence.