Contingency tables - test for independence
Calculator (TI-82) help for calculation of the test statistic.
(This works for the TI-83/84 also, but
calculator has its own, better technique using matrices.
See your text book)
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1. Put the observed values in list L1.
2. Put the expected values in list L2. These are the values in the table in parentheses. The calculation
for the expected values is E = (row total)(column total)/(grand total).
3. Calculate the test statistic (chi - square) as follows:
sum((L1 - L2)^2/L2)
where "sum" is found in 2nd List MATH menu
4. The test statistic for the above example is:
(chi-square) = 9.3323