Data Analysis with Microsoft Excel: Updated for Office 2007

Chapter 6 Statistical Inference 237

3 Click Explore Hypothesis Testing from the Table of Contents column.

See Figure 6-7.

Figure 6-7

The

Hypothesis
Testing
workbook

click

highlighted

boxes to

change

conditions

The workbook shows the sampling distribution under the null hypoth-

esis, where it is assumed that m 5 50. The rejection region is displayed on

the chart in black. This workbook allows you to vary four values—s, x, the

sample size, and a—to see their effect on the hypothesis test. You can also

choose whether to perform a one-tailed or a two-tailed test. The results of

your choices are automatically displayed on the workbook and in the chart.

By working with different values of these factors, you can get a clearer pic-

ture of how hypothesis testing works.

For example, what impact would doubling the sample size have on the

hypothesis test, assuming all other factors remained the same? Let’s fi nd out.

To increase the sample size:

1 Click the Sample Size box, and change the sample size from 25 to 50.

See Figure 6-8.