A
AcadiFi
ES
expected_shortfall2026-05-21
cfaLevel IQuantitative MethodsHypothesis Testing

How do I compare a p-value to alpha in CFA hypothesis testing?

If the question gives p-value and alpha, do I need to think about the critical value too, or can I make the decision directly?

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If the question gives the p-value and alpha, make the decision directly: reject the null when p-value <= alpha; otherwise fail to reject the null.

Use one decision route at a time. The p-value route compares p-value to alpha. The critical-value route compares the test statistic to the critical value. Mixing those routes is a common mistake.

Example: Rowan Analytics tests whether average forecast error differs from zero. The two-tailed p-value is 0.047, and the test uses alpha = 0.05. Because 0.047 <= 0.05, reject the null at the 5% level. If the same question used alpha = 0.01, fail to reject because 0.047 > 0.01.

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