A First Course in Statistics, 12th Edition

7.2 Comparing Two Population Means: Independent Sampling

In this section, we develop both large-sample and small-sample methodologies for comparing two population means. In the large-sample case, we use the z-statistic; in the small-sample case, we use the t-statistic.

Large Samples

DIETS Example 7.1 A Large-Sample Confidence Interval for $({\mu }_1-{\mu }_2)$ —Comparing Mean Weight Loss for Two Diets 

Problem

1. A dietitian has developed a diet that is low in fats, carbohydrates, and cholesterol. Although the diet was initially intended to be used by ...