The chi-square (χ2) test concerns the proportions of some characteristic among different groups. It determines whether the difference in proportions observed from samples is likely to reflect real differences in the underlying population, or if it may simply be due to random variation.
The chi-square test is an approximation to Fisher's exact test, and can be applied when the data set is too large for Fisher's to be feasible. The Yates continuity correction to the chi-square test should be applied when there two groups and some of the numbers are small. Biostats Calculator will automatically select the best available test.
After selecting χ2 and Fisher exact from the menu, simply enter the number of individuals with and without the characteristic, for each group being studied. Biostats Calculator will determine the appropriate calculation and perform a hypothesis test to determine whether there is a statistically significant difference between the groups.
Biostats Calculator reports:
Even if another type of test is used, the uncorrected χ2 and p value can be accessed by tap-and-holding the reported p value.
Biostats Calculator can perform this test and 11 others from the convenience of your iPhone or iPod Touch. Buy it today!
