TwoSided

is an option to hypothesis test functions that specifies whether the test should be two-sided.

With default setting False, the p-value is associated with the smaller tail of the distribution of the test statistics.

With True, the p-value is split between the two tails of the distribution of the test statistic.

The p-value for a one-sided test:

Needs["HypothesisTesting`"]

The p-value for a one-sided test:

Out[2]=

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