Value to compare the sample percentage to
Value measured from sample or expected from sample
(Probability of incorrectly rejecting the null hypothesis that there is no difference in the percentage values). An Alpha of 5% corresponds to a 95% Confidence Interval.
(Probability of incorrectly failing to reject the null hypothesis that there is NO difference in the percentage values — assuming no difference when a real difference exists). A Beta of 50% is used in most simple calculations of sampling error.