Questions: Complete the hypothesis test with the alternative hypothesis μd>0 based on the paired data that follow and d=B-A. Use α=0.05. Assume normality.
A 700 830 860 1080 930 B 720 820 890 1100 960
B: Solve using the evalue approach. n= , 𝑑̅=20 x, 5 d=10
Hypothesis Test:
H0: μd=0 vs. Ha: μd>0
Solve for t.
t =4.47
Use t to find the p-value. p-value: 0.0025
Decision for the p-value Approach: Reject H0, p-value < α
Find t(df, a).
t(df, a)=2.353
Decision for the Classical Approach: Reject H0, t >t(df, a)
Transcript text: Complete the hypothesis test with the alternative hypothesis $\mu_{d}>0$ based on the paired data that follow and $d=B-A$. Use $\alpha=0.05$. Assume normality.
A 7008308601080930 B 7208208901100960
B: Solve using the evalue approach. $n=$ $\qquad$ , $\bar{d}=20$ $x, 5 d=10$
Hypothesis Test:
\[
\begin{array}{l}
H_{0}: \mu_{d}=0 \text { vs. } H_{a}: \mu_{d}>0 \\
\end{array}
\]
Solve for $t$.
\[
t *=4.47
\]
Use t* to find the p-value. p -value: $0.0025$
Decision for the $p$-value Approach: Reject $\mathrm{H}_{0}$, p-value < $\alpha$
Find $t(d f, a)$.
\[
t(d f, a)=2.353
\]
Decision for the Classical Approach: Reject $H_{0}, t *>t(d f, a)$
Solution
Solution Steps
Step 1: Data Summary
We have paired data from two groups, \( A \) and \( B \), with the following values:
\( A = [700, 830, 860, 1080, 930] \)
\( B = [720, 820, 890, 1100, 960] \)
The differences \( d = B - A \) are calculated as follows:
\[
d = [20, -10, 30, 20, 30]
\]
Step 2: Calculate Sample Statistics
The sample size \( n \) is:
\[
n = 5
\]
The mean of the differences \( \bar{d} \) is:
\[
\bar{d} = \frac{20 + (-10) + 30 + 20 + 30}{5} = 18.0
\]
The sample standard deviation \( s_d \) is calculated as:
\[
s_d = \sqrt{\frac{\sum (d_i - \bar{d})^2}{n - 1}} \approx 16.4317
\]
The standard error (SE) of the mean difference is:
\[
SE = \frac{s_d}{\sqrt{n}} = \frac{16.4317}{\sqrt{5}} \approx 7.3485
\]
Step 3: Calculate Test Statistic
The test statistic \( t \) is calculated using the formula:
\[
t = \frac{\bar{d}}{SE} = \frac{18.0}{7.3485} \approx 2.4489
\]
Step 4: Determine Critical Value and p-value
For a two-tailed test at \( \alpha = 0.05 \) with \( df = n - 1 = 4 \), the critical value \( t_{\alpha/2, df} \) is:
\[
t_{(0.025, 4)} \approx 2.7764
\]
The p-value is calculated as:
\[
P = 2 \times (1 - T(|t|)) = 2 \times (1 - T(2.4489)) \approx 0.0705
\]
Step 5: Decision Making
Since \( p \text{-value} = 0.0705 \) is greater than \( \alpha = 0.05 \), we fail to reject the null hypothesis \( H_0 \).
The test statistic \( t \approx 2.4489 \) is less than the critical value \( t_{(0.025, 4)} \approx 2.7764 \), confirming the decision to fail to reject \( H_0 \).
Final Answer
The conclusion of the hypothesis test is that we fail to reject the null hypothesis \( H_0: \mu_d = 0 \) in favor of the alternative hypothesis \( H_a: \mu_d > 0 \).