Question

State whether the standardized test statistic z indicates that you should reject the null hypothesis. Right tailed: Z₀ = 1.285

(a) z = 1.311
​(b) z = 1.065
​(c) z = -1.148
​(d) z = 1.525

Answer 1

The null hypothesis should be rejected for z = -1.148 and not rejected for other test statistics.

Step-by-step explanation:

The critical value for a right-tailed test with significance level α = 0.05 is 1.645. If the test statistic z is greater than the critical value, it indicates that you should reject the null hypothesis. Let's check the given test statistics:

1. z = 1.311: 1.311 > 1.645, so we do not reject the null hypothesis.
2. z = 1.065: 1.065 > 1.645, so we do not reject the null hypothesis.
3. z = -1.148: -1.148 < 1.645, so we reject the null hypothesis.
4. z = 1.525: 1.525 > 1.645, so we do not reject the null hypothesis.

Therefore, based on the provided test statistics, we should reject the null hypothesis for (c) z = -1.148 and do not reject the null hypothesis for the others.