What is the smallest level of significance at which the null hypothesis will be rejected, assuming the null is true?

What is the smallest level of significance at which the null hypothesis will be rejected, assuming the null is true?

• A. p-value (observed level of significance)
• B. Critical value
• C. Power
• D. Confidence level

Answer: (A)

The p-value is the smallest significance level at which you would reject the null hypothesis, assuming the null is true. It represents the probability, under H0, of obtaining results as extreme or more extreme than what was observed. Since you reject H0 if the p-value is less than or equal to your chosen alpha, the pivotal alpha that just leads to rejection is exactly the observed p-value. Other concepts don’t serve this role: the critical value depends on a selected alpha and serves as a cutoff for the test statistic, power is about the likelihood of correctly rejecting a false null, and confidence level relates to interval estimation, not a direct rejection threshold.

The p-value is the smallest significance level at which you would reject the null hypothesis, assuming the null is true. It represents the probability, under H0, of obtaining results as extreme or more extreme than what was observed. Since you reject H0 if the p-value is less than or equal to your chosen alpha, the pivotal alpha that just leads to rejection is exactly the observed p-value. Other concepts don’t serve this role: the critical value depends on a selected alpha and serves as a cutoff for the test statistic, power is about the likelihood of correctly rejecting a false null, and confidence level relates to interval estimation, not a direct rejection threshold.