Example of Chi-Square Test for Association
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You are interested in the relationship between gender and political party affiliation. You query 100 people about their political affiliation and record the number of males (row 1) and females (row 2) for each political party. The worksheet data appears as follows:

C1

C2

C3

Democrat

Republican

Other

28

18

4

22

27

1

1    Open the worksheet EXH_TABL.MTW.

2    Choose Stat > Tables > Chi-Square Test for Association.

3    Choose Summarized data in a two-way table.

4    In Columns containing the table, enter Democrat Republican Other. Click OK.

Session window output

Chi-Square Test for Association: Worksheet rows, Worksheet columns

 

 

Rows: Worksheet rows   Columns: Worksheet columns

 

       Democrat  Republican  Other  All

 

1            28          18      4   50

          25.00       22.50   2.50

 

2            22          27      1   50

          25.00       22.50   2.50

 

All          50          45      5  100

 

Cell Contents:      Count

                    Expected count

 

 

Pearson Chi-Square = 4.320, DF = 2, P-Value = 0.115

Likelihood Ratio Chi-Square = 4.461, DF = 2, P-Value = 0.107

 

* NOTE * 2 cells with expected counts less than 5

Interpreting the results

Both p-values are greater than 0.05. Thus, there is no evidence of an association between gender and political party affiliation. Of the 6 cells, 2 have expected counts less than five (33%). Therefore, even if you had a significant p-value for these data, you should interpret the results with caution. To be more confident of the results, repeat the test, omitting the Other category.