Furthermore, statistical estimates suggest that as much as 90% of the reason that women have families of a particular size is simply because that is the number of children they want.

ECONOMIST: Population control

In order for his statistical estimates to be valid, he has to assume that a poor couple which decides to have a child needs the same proportionate increase in spending to maintain its living standard as a rich couple.

ECONOMIST: The war over poverty

The county vote is put into statistical models and estimates and projections are made.

CNN: How does CNN make election projections?