If you are going to compare someone to anything you have to make that someone the middle... for example if I am going to compare you to guys in your town with an IQ of 150 (your IQ), it is doubtful I can find enough geniuses like yourself, with an exact IQ of 150, in your small town to get a large enough sample. So I'd have to get some people who have close to, but not exactly your IQ.
If I compared you to guys with your IQ and below I'd get you and 10 people obviously inferior to your genius. If I compared you to guys with your IQ and above you'd be the dumbest of the group.
So I'd need to make a group where you are average, the group would have you, some guys close, but below you, and some guys (and girls too) close but above you... so you are the average representation of the group.