Question

zachary completes a hypothesis test and finds that he rejects the null hypothesis. which statement gives a reason for rejecting the null hypothesis?
the z - statistic is less than 0.
the z - statistic lies in the critical region.
the z - statistic lies outside the critical region.
the z - statistic is greater than 0.

Explanation:

In hypothesis testing, the null hypothesis is rejected when the test statistic (here, z - statistic) lies in the critical region. The critical region is the set of values for which we reject the null hypothesis. A z - statistic being less than 0 or greater than 0 does not directly determine rejection; what matters is if it's in the critical region (which depends on the significance level and the type of test, like one - tailed or two - tailed). If the z - statistic is outside the critical region, we fail to reject the null hypothesis. So the correct reason for rejecting the null hypothesis is that the z - statistic lies in the critical region.

Answer:

B. The z - statistic lies in the critical region.