Data Analysis with Microsoft Excel: Updated for Office 2007

210 Fundamentals of Statistics

6 Click the Output button, and then click the New Worksheet option

button and type Sample Average Statistics for the new worksheet

name. Click the OK button.

7 Click the OK button to generate the sample statistics.

8 Select the range B4:B5 and reduce the number of decimal places to 3.

Figure 5-22 shows the sample output (yours will be slightly different).

Figure 5-22

Sample

average

statistics

9 Close the workbook with the random samples. You don’t have to

save your changes.

As you would expect, the average of the sample averages is near zero since

the averages come from standard normal values in which m is equal to zero.

The standard deviation of the sample averages is 0.256. Thus the sampling

distribution of the average values taken from samples with sample sizes of 16

appears to follow a normal distribution with m of 0 and a s of about 0.25.

Is there a relationship between sample size and the value for the standard

deviation?