Concept explainers
Applying the Concepts 10–3
Interpreting Simple Linear Regression
Answer the questions about the following computer-generated information.
Linear
Coefficient of determination = 0.631319
Standard error of estimate = 12.9668
Explained variation = 5182.41
Unexplained variation = 3026.49
Total variation = 8208.90
Equation of regression line y′ = 0.725983x + 16.5523
Level of significance = 0.1
Test statistic = 0.794556
Critical value = 0.378419
1. Are both variables moving in the same direction?
2. Which number measures the distances from the prediction line to the actual values?
3. Which number is the slope of the regression line?
4. Which number is the y intercept of the regression line?
5. Which number can be found in a table?
6. Which number is the allowable risk of making a type I error?
7. Which number measures the variation explained by the regression?
8. Which number measures the scatter of points about the regression line?
9. What is the null hypothesis?
10. Which number is compared to the critical value to see if the null hypothesis should be rejected?
11. Should the null hypothesis be rejected?
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Elementary Statistics: A Step By Step Approach
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