Conduct a Chi-square test with aggregate data in Stata

In Stata, both the tabulate and tabi commands conduct the Pearson's Chi-square test. The tabulate (may be abbreviated as tab) command produces one- or two-way frequency tables given one or two variables. The commands also can run a Chi-square test using the chi2 option:

tab grade gender, chi2

The above command will produce a cross-table of grade and gender and its Chi-square statistic.

When you do not have individual data, but only aggregate frequencies, use the tabi command. You must list the frequencies of each cell with a backward slash (\) to separate a row of a table. Consider the following examples:

• tabi 22 44 \ 34 56, chi2
• tabi 34 45 \ 34 53 \ 34 34, chi2
• tabi 34 45 36 \ 34 64 96, chi2

The first command conducts a Chi-square test for a 2x2 table, while the second and third commands run the test for 3x2 and 2x3 tables, respectively.