EXAMPLE 2.36

The marginal distribution of age. Look at the table in Example 2.34. The total numbers of children aged 5 to 10 and children aged 11 to 13 are given in the bottom row, labeled “Total.” Our sample has 1055 children aged 5 to 10 and 974 children aged 11 to 13. To find the marginal distribution of age, we simply divide these numbers by the total sample size, 2029. The marginal distribution of age is

Note that the proportions sum to 1; there is no roundoff error.