Venn diagrams are used to sort sets of data. The probability of an event not happening uses the complement of the region on the Venn diagram. Count the number of elements in each region.

If you specify the option METHOD=PPS, PROC SURVEYSELECT selects units with probability proportional to size and without ... Refer to Fox (1989), Golmant (1990), and Watts (1991) for details. Notation ...