Questions: A test of H0: μ=53 versus H1: μ ≠ 53 is performed using a significance level of α=0.05. The value of the test statistic is z=-1.97.
Determine whether to reject H0.
Transcript text: A test of $H_{0}: \mu=53$ versus $H_{1}: \mu \neq 53$ is performed using a significance level of $\alpha=0.05$. The value of the test statistic is $z=-1.97$.
Determine whether to reject $H_{0}$.
Solution
Solution Steps
Step 1: Determine the Critical Z-Values
For a two-tailed hypothesis test at a significance level of \( \alpha = 0.05 \), the critical z-values can be calculated using the formula:
\[
Z = \Phi^{-1}\left(1 - \frac{\alpha}{2}\right)
\]
Substituting \( \alpha = 0.05 \):
\[
Z = \Phi^{-1}(1 - 0.025) = \Phi^{-1}(0.975)
\]
The critical z-values are found to be:
\[
\text{Critical z-values: } \pm 1.96
\]
Step 2: Compare the Test Statistic with Critical Values
The test statistic given is \( z = -1.97 \). We compare this value with the critical z-values:
Critical region for rejection of \( H_0 \): \( z < -1.96 \) or \( z > 1.96 \)
Since \( -1.97 < -1.96 \), the test statistic falls within the critical region.
Step 3: Make a Decision
Since the test statistic \( z = -1.97 \) is in the critical region, we reject the null hypothesis \( H_0: \mu = 53 \) at the \( \alpha = 0.05 \) level.
Final Answer
We reject the null hypothesis \( H_0 \) at the \( \alpha = 0.05 \) level.