Income distribution data is an example of continuous data (weekly income may be a fraction of the base currency amount), an empirical distribution (it is derived from real data, not a theoretical model), bounded below (there are no negative incomes), unbounded above (although there is always some maximum income at any point in time, there is often no fundamental limit), an asymmetric distribution (the shape is very skewed with a large number of smaller incomes and small number of larger ones ), and a long-tail distribution (there are a small number of extremely large incomes). Furthermore, for practical purposes it effectively has infinite variance (larger and larger samples typically have larger and larger variances).

Used on pages 47, 50, 51