0 p-value
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Decision at α
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Z-score used
The p-value is computed from the standard normal distribution. If p ≤ α you reject the null hypothesis; otherwise you fail to reject it.
Frequently Asked Questions
What is a p-value?
The p-value is the probability of observing a result at least as extreme as your test statistic if the null hypothesis were true. A small p-value (≤ α, often 0.05) is evidence against the null hypothesis.
Calculate the p-value from a z-score for one- or two-tailed hypothesis tests.