IDNLearn.com: Where curiosity meets clarity and questions find their answers. Join our community to access reliable and comprehensive responses to your questions from experienced professionals.
Sagot :
To determine whether a simple linear regression model provides useful information for predicting growth rate from research and development expenditure, we will follow these steps:
### Part (a): Hypothesis Testing
Step 1: State the hypotheses
- Null Hypothesis ([tex]\(H_0\)[/tex]): There is no significant linear relationship between growth rate and research and development expenditure ([tex]\( \beta = 0 \)[/tex]).
- Alternative Hypothesis ([tex]\(H_a\)[/tex]): There is a significant linear relationship between growth rate and research and development expenditure ([tex]\( \beta \neq 0 \)[/tex]).
Step 2: Calculate the test statistic
From linear regression analysis, we have the slope [tex]\( \beta \)[/tex], standard error of the slope [tex]\( SE_{\beta} \)[/tex], and the t-statistic.
Given:
- Test statistic [tex]\( t = 2.28 \)[/tex]
Step 3: Determine the p-value
We use the t-statistic to find the corresponding p-value.
Given:
- [tex]\( P \text{-value} = 0.0625 \)[/tex]
Since the p-value (0.0625) is greater than the significance level of 0.05, we compare it with the significant level as follows:
Step 4: Draw a conclusion
Since the p-value (0.0625) is greater than the significance level (0.05), we fail to reject the null hypothesis.
Conclusion:
Fail to reject [tex]\( H_0 \)[/tex]. We do not have convincing evidence of a useful linear relationship between growth rate and research and development expenditure.
### Part (b): Confidence Interval for Slope
Step 1: Calculate the confidence interval for the slope
We want to construct a 90% confidence interval for the average change in growth rate associated with a [tex]$1,000,000 increase in expenditure. Given: - slope (\( \beta \)) = 0.5751273930806419 - standard error of the slope (\( SE_{\beta} \)) = 0.25184706198095234 The critical value for a 90% confidence interval with 6 degrees of freedom (\( df = n - 2 \)) is approximately 1.943. Step 2: Compute the confidence interval The formula for the confidence interval is: \[ \text{Slope CI} = \beta \pm \text{critical t} \times SE_{\beta} \] Given: - Lower bound = 0.08576954016490956 - Upper bound = 1.0644852459963743 Hence, the confidence interval is: \[ 0.086 \leq \beta \leq 1.064\] ### Conclusion: (a) - Test Statistic: \( t = 2.28 \) - P-value: \( P = 0.0625 \) - Conclusion: Fail to reject \( H_0 \). We do not have convincing evidence of a useful linear relationship between growth rate and research and development expenditure. (b) - The 90% confidence interval for the average change in growth rate associated with a $[/tex]1,000,000 increase in expenditure is approximately [tex]\([0.086, 1.064]\)[/tex] percent per year.
### Part (a): Hypothesis Testing
Step 1: State the hypotheses
- Null Hypothesis ([tex]\(H_0\)[/tex]): There is no significant linear relationship between growth rate and research and development expenditure ([tex]\( \beta = 0 \)[/tex]).
- Alternative Hypothesis ([tex]\(H_a\)[/tex]): There is a significant linear relationship between growth rate and research and development expenditure ([tex]\( \beta \neq 0 \)[/tex]).
Step 2: Calculate the test statistic
From linear regression analysis, we have the slope [tex]\( \beta \)[/tex], standard error of the slope [tex]\( SE_{\beta} \)[/tex], and the t-statistic.
Given:
- Test statistic [tex]\( t = 2.28 \)[/tex]
Step 3: Determine the p-value
We use the t-statistic to find the corresponding p-value.
Given:
- [tex]\( P \text{-value} = 0.0625 \)[/tex]
Since the p-value (0.0625) is greater than the significance level of 0.05, we compare it with the significant level as follows:
Step 4: Draw a conclusion
Since the p-value (0.0625) is greater than the significance level (0.05), we fail to reject the null hypothesis.
Conclusion:
Fail to reject [tex]\( H_0 \)[/tex]. We do not have convincing evidence of a useful linear relationship between growth rate and research and development expenditure.
### Part (b): Confidence Interval for Slope
Step 1: Calculate the confidence interval for the slope
We want to construct a 90% confidence interval for the average change in growth rate associated with a [tex]$1,000,000 increase in expenditure. Given: - slope (\( \beta \)) = 0.5751273930806419 - standard error of the slope (\( SE_{\beta} \)) = 0.25184706198095234 The critical value for a 90% confidence interval with 6 degrees of freedom (\( df = n - 2 \)) is approximately 1.943. Step 2: Compute the confidence interval The formula for the confidence interval is: \[ \text{Slope CI} = \beta \pm \text{critical t} \times SE_{\beta} \] Given: - Lower bound = 0.08576954016490956 - Upper bound = 1.0644852459963743 Hence, the confidence interval is: \[ 0.086 \leq \beta \leq 1.064\] ### Conclusion: (a) - Test Statistic: \( t = 2.28 \) - P-value: \( P = 0.0625 \) - Conclusion: Fail to reject \( H_0 \). We do not have convincing evidence of a useful linear relationship between growth rate and research and development expenditure. (b) - The 90% confidence interval for the average change in growth rate associated with a $[/tex]1,000,000 increase in expenditure is approximately [tex]\([0.086, 1.064]\)[/tex] percent per year.
Your participation means a lot to us. Keep sharing information and solutions. This community grows thanks to the amazing contributions from members like you. IDNLearn.com provides the best answers to your questions. Thank you for visiting, and come back soon for more helpful information.