Module 10 Assignment: Two Independent Samples

The purpose of this activity is to give you guided practice in obtaining and interpreting a 95% confidence interval for μ1 − μ2 following a two-sample T-test that rejected H0. Recall our second example:

Our variable Age Group (X) has two categories: males 20–29 years old and males 75+ years old. These two groups form our two populations. For each population we have a separate μ, representing the weight (Y) mean of that population. For each population we take an SRS. From population 1 of males 20–29 years old, we obtain an SRS of size 712, and find that it has a mean of 83.4 and SD of 18.7. From population 2 of males 75+ years old, we take an SRS of size 1001 and find that it has a mean of 78.5 and SD of 19.0.

Instructions

Click on the link corresponding to your statistical package to see instructions for completing the activity, and then answer the questions below.

StatCrunch Minitab Excel TI Calculator

Question:

Obtain the 95% confidence interval for μ1 – μ2 and interpret it in context.