Data Analysis with Microsoft Excel: Updated for Office 2007

Chapter 5 Probability Distributions 211

CONCEPT TUTORIALS

Sampling Distributions

You can use the exploration workbook Population Parameters to explore

how sample size affects the distribution of the sample average.

To explore sampling distributions:

1 Open the fi le Population Parameters, from the Explore folder, en-

abling the macros the workbook contains.

2 The workbook contains information on parameters and sampling

distributions. Review the material.

3 Click Exploring Sampling Distributions from the Table of Contents.

4 The worksheet displays a histogram of 150 sample averages. A scroll

bar allows you to change the size of each sample from 1 up to 16.

5 Move the scroll bar and observe how the shape of the distribution

changes on the basis of the different sample sizes. Also note how the

value of the standard deviation changes.

Figure 5-23 shows the sampling distribution for different sample

sizes. Do you see a pattern in the values of the standard deviation

compared to the sample size?

Figure 5-23
Variability
Statistics

sample size = 1 sample size = 4

sample size = 9 sample size = 16