Chi
Square tests in Excel
There are different types of Chi Square tests:
Chi
Square test of a Contingency Table
Watch Chi Square Test of a Contingency Table in Excel Video
A Chi Square test evaluates if two
variables are independent of each other. We've all taken surveys and probably
wondered what happened. A Chi Square test of a contingency table helps identify
if there are differences between two or more demographics. Consider the following
example.
Men vs Women - Chi Square test Example
Imagine asking men and women if they agree, disagree or are neutral
about a given topic. How will we know if they have the same or differing
opinions? We can develop a null hypothesis (H0) that
men and women have independent views and an alternate hypothesis
(Ha) that their views are related:
- H0 men <> women
- Ha men =women
Now, conduct
the survey and enter the number of responses into Excel. As you can see, men seem
to agree more than the women do, but is it statistically different? 
Select
the data with the mouse and click on the QI Macros Menu to select the one sample
Chi Square test: 
The Chi Square test macro will calculate the values and interpret
the results for you:

Note
that we don't need the same number of responses from each group to get a result. Interpreting
the Chi Square results
|
If
|
Then
|
|
| p value < a |
Reject the null hypothesis |
Variables are Related |
| p value > a |
Accept the null hypothesis |
Variables are Independent |
In the above results the p value is
0.00031.
If the p value is less than the significance (e.g., a=0.05),
we can reject the null hypothesis that men and women have independent
views on the subject.
Chi square is just one of the tools in the QI
Macros Statistical Process Control Software for Excel. Other tools include: Download
the FREE 30-day Evaluation copy of the QI Macros Excel SPC Software for Six Sigma
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