Three distinct tests are available,

Three distinct tests are available, all concerned with the same null hypothesis Ho (= random union of gametes). The difference between them is the construction of the rejection zone. For the Probability-test (sub-option 3), the probability of the observed sample is used to define the rejection zone, and the P-value of the test corresponds to the sum of the probabilities of all tables (with the same allelic counts) with the same or lower probability. This is the "exact HW test" of Haldane (1954), Weir (1990b), Guo and Thompson (1992) and others. When the alternative hypothesis (H1) of interest is heterozygote excess or deficiency, more powerful tests than the probability-test can be used (see Rousset and Raymond, 1995). One of them, the score test (U test), is available here, either for H1 = heterozygote deficiency (sub-option 1) or H1 = heterozygote excess (sub-option 2). The multi-samples version of these two tests are accessible through sub-options 4 or 5.