Chapter 13 Lin ear ear Regressio Regressio n and Corr Corr elatio elatio n Multiple Choice
Use the following to answer questions 133-138: Given the following five points: (–2,0), (–1,0), (0,1), (1,1), and (2,3). 133. What is the slope of the line? line? A) 0.0 B) 0.5 C) 0.6 D) 0.7 Answer: D 134. What is the Y intercept? intercept? A) 0.0 B) 0.7 C) 1.0 D) 1.5 Answer: C 135. What is the standard error of the the estimate? A) 0 B) 0.135 C) 0.367 D) 0.606 Answer: D 136. What is the critical value necessary necessary to determine a confidence confidence interval for a 95% level of confidence? A) 2.132 B) 2.353 C) 2.776 D) 3.182 Answer: D 137. What is the critical value necessary necessary to determine a confidence confidence interval for a 90% level of confidence? A) 1.533 B) 1.638 C) 2.132 D) 2.353 Answer: D
ˆ = 2 – 0.4 X , what is the value of Y ˆ when X = 138. If the regression regression equation is Y = –3? A) 0.8 B) 3.2 C) –10.0 D) 14.0 Answer: B
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Fill-in-the-Blank
Use the following to answer questions 139-145: A company wants to study the relationship between an employee's length of e mployment and their number of workdays absent. The company collected the following information on a random sample of seven employees.
Number of Workdays Absent Length of Employment (in yrs)
2 5
3 6
3 9
5 4
7 2
7 2
8 0
141. What is the slope of the linear equation? ________________ Answer: -0.6852 142. What is the Y intercept of the linear equation? ______________ Answer: 7.7407 143. What is the least squares equation for the data? ___________________
ˆ = 7.7107 - 0.6852 X Answer: Y 145. What is the standard error of estimate? _____________ Answer: 1.31 Use the following to answer questions 146-150: The relationship between interest rates as a percent ( X ) and housing starts (Y ) is given by the linear
ˆ = 4094 – 269 X . equation Y 146. What will be the number of housing starts if the interest rate is 8.25%? ___________ Answer: 1875 (1874.75) 147. What will be the number of housing starts if the interest rate rose to 16%? __________ Answer: zero (0) since you can't have negative housing starts 148. At what interest rate will there be no permits for housing starts? _________ Answer: 15.22 150. For what interest rate will the maximum number of housing starts be achieved? _______ Answer: 0 Multiple Choice
Use the following to answer questions 151-160: A sales manager for an advertising agency believes there is a relationship between the number of contacts and the amount of the sales. To verify this belief, the following data was collected:
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Salesperson 1 2 3 4 5 6 7 8 9 10
Number of Contacts 14 12 20 16 46 23 48 50 55 50
Sales (in thousands) 24 14 28 30 80 30 90 85 120 110
153. What is the Y -intercept of the linear equation? A) –12.201 B) 2.1946 C) –2.1946 D) 12.201 Answer: A 154. What is the slope of the linear equation? A) –12.201 B) 12.201 C) 2.1946 D) –2.1946 Answer: C 155. What is the value of the standard error of estimate? A) 9.3104 B) 8.778 C) 8.328 D) 86.68 Answer: A 156. What is the value of the coefficient of correlation? A) 0.6317 B) 0.9754 C) 0.9513 D) 9.3104 Answer: B 157. What is the value of the coefficient of determination? A) 9.3104 B) 0.9754 C) 0.6319 D) 0.9513 Answer: D
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Test Bank, Chapter 13
158. The 95% confidence interval for 30 calls is A) 55.8, 51.5 B) 51.4, 55.9 C) 46.7, 60.6 D) 31.1, 76.2 Answer: C 159. The 95% prediction interval for a particular person making 30 calls is A) 55.8, 51.5 B) 51.4, 55.9 C) 46.7, 60.6 D) 31.1, 76.2 Answer: D 160. What is the regression equation?
ˆ = 2.1946 – 12.201 X A) Y ˆ = –12.201 X + 2.1946 X B) Y ˆ = 12.201 + 2.1946 X C) Y
ˆ = 2.1946 + 12.201 X D) Y Answer: B 166. If testing the hypothesis: H0: ρ = 0, the computed t – statistic is: A) 9.45 B) 8.84 C) 8.18 D) Cannot be computed Answer: A
ˆ when X = 4. 167. Estimate the value of Y A) 10.45 B) 3.73 C) 8.20 D) Cannot be computed Answer: C
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