Microsoft Office Tutorials and References

In Depth Information

3.2.3.1 STEP 1: State the null hypothesis and the research hypothesis

If you are using numerical scales in your survey, you need to remember that these

hypotheses refer to the “middle” of the numerical scale. For example, if you are

using 7-point scales with 1

¼

poor and 7

¼

excellent, these hypotheses would refer

to the middle of these scales and would be:

Null hypothesis H
0
:

m
¼
4

Research hypothesis H
1
:

m
6¼

4

3.2.3.2 STEP 2: Select the appropriate statistical test

In this chapter we are studying the conﬁdence interval about the mean, and so we

will select that test.

3.2.3.3 STEP 3: Calculate the formula for the statistical test

You will recall (see Section
3.1.5
) that the formula for the conﬁdence interval about

the mean is:

X

ts

e

(3.2)

:

:

We discussed the procedure for computing this formula for the conﬁdence

interval about the mean using Excel earlier in this chapter, and the steps involved

in using that formula are:

1. Use Excel’s

¼

count function to ﬁnd the sample size.

2. Use Excel’s

¼

average function to ﬁnd the sample mean,
X
.

3. Use Excel’s

STDEV function to ﬁnd the standard deviation, STDEV.

4. Find the standard error of the mean (s.e
.
) by dividing the standard deviation

(STDEV) by the square root of the sample size, n.

5. Use Excel’s TINV function to ﬁnd the lower limit of the conﬁdence interval.

6. Use Excel’s TINV function to ﬁnd the upper limit of the conﬁdence interval.

¼

Search JabSto ::

Custom Search