ABSTRACT
Rates of occurrence In public health we often need to measure the rate at which an event occurs, such as how often in a series of DNA samples a particular configuration appears or how often in families of a given size a particular ratio of boys to girls among their offspring presents. By way of example, let us ask: In a family of six children, what is the probability that 4 will be boys and 2 girls? (see p. 26).
