[sickpig]

average is skewed towards distribution outliers, the more asymmetric the distribution the more pronounced will be such effect.

On the other hand median just gives you the value that split the distribution in two exact parts.

Price/Income distributions are the perfect match if you want to see avg bias taken to its extreme.

e.g.

median of [2,2,2,2,2,2,2,100] = 2 average of [2,2,2,2,2,2,2,100] = 14.25