512 Chapter 11:Goodness of Fit Tests and Categorical Data Analysis
Determine the p-value of the test that a family’s income and region are
independent.
16.The following data relate the mother’s age and the birthweight (in grams) of her
child.
Birthweight
Maternal Age Less Than 2,500 Grams More Than 2,500 Grams
20 years or less 10 40
Greater than 20 15 135
Test the hypothesis that the baby’s birthweight is independent of the mother’s age.
17.Repeat Problem 16 with all of the data values doubled — that is, with these data:
20 80
30 270
18.The number of infant mortalities as a function of the baby’s birthweight (in grams)
for 72,730 live white births in New York in 1974 is as follows:
Outcome at the End of 1 Year
Birthweight Alive Dead
Less than 2,500 4,597 618
Greater than 2,500 67,093 422
Test the hypothesis that the birthweight is independent of whether or not the baby
survives its first year.
19.An experiment designed to study the relationship between hypertension and
cigarette smoking yielded the following data.
Nonsmoker Moderate Smoker Heavy Smoker
Hypertension 20 38 28
No hypertension 50 27 18
Test the hypothesis that whether or not an individual has hypertension is
independent of how much that person smokes.
20.The following table shows the number of defective, acceptable, and superior items
in samples taken both before and after the introduction of a modification in the
manufacturing process.