Chapter 15 Quiz

1/10/24, 7:42 PM Chapter 15 Quiz: OSC 3440-090 Fall 2023 App of Business Stats https://utah.instructure.com/courses/891130/quizzes/3248145 3/23 3.33 / 3.33 pts Question 4 The editors of a national automotive magazine recently studied 30 different automobiles sold in the United States with the intent of seeing whether they could develop a multiple regression model to explain the variation in highway miles per gallon. A number of different independent variables were collected. The following regression output (with some values missing) was recently presented to the editors by the magazine's analysts: Based on this output and your understanding of multiple regression analysis, what is the critical value for testing the significance of the overall regression model at a 0.05 level of statistical significance? Nearly F = 3.80 About F = 5.92 Approximately F = 2.50 None of the above

1/10/24, 7:42 PM Chapter 15 Quiz: OSC 3440-090 Fall 2023 App of Business Stats https://utah.instructure.com/courses/891130/quizzes/3248145 6/23 3.33 / 3.33 pts Question 8 Under what circumstances does the variance inflation factor signal that multicollinearity may be a problem? When the VIF is a negative value When the VIF is greater than or equal to 5 When the value of VIF exceeds the size of the sample from which the regression model was developed When the VIF value is approximately 1.0 3.33 / 3.33 pts Question 9 A multiple regression is shown below for a data set of yachts where the dependent variable is the price of the boat in thousands of dollars. Given this information, what percentage of variation in the dependent variable is explained by the regression model? About 37 percent

1/10/24, 7:42 PM Chapter 15 Quiz: OSC 3440-090 Fall 2023 App of Business Stats https://utah.instructure.com/courses/891130/quizzes/3248145 9/23 Given this plot, which of the following models would likely give the best fit? = b + b t + b t + b t 0 1 1 2 1 3 = b + b t + b t 0 1 1 2 = b b + b t 0 1 1 = b + b t + b t + b t + b t 0 1 1 2 3 3 4 4 3.33 / 3.33 pts Question 13 If a decision maker wishes to develop a regression model in which the University Class Standing is a categorical variable with 5 possible levels of response, then he will need to include how many dummy variables? 4 1

1/10/24, 7:42 PM Chapter 15 Quiz: OSC 3440-090 Fall 2023 App of Business Stats https://utah.instructure.com/courses/891130/quizzes/3248145 12/23 Based on this output and your understanding of multiple regression analysis, which of the following statements is true? The standard error of the estimate is a negative value due to the multicollinearity problems in the model. The overall multiple regression model explains a significant portion of the variation in highway mileage when tested at a significance level of 0.05. Only the two independent variables are statistically significant in the presence of the others when a significance level of 0.05 is used to test. None of the above is true. 3.33 / 3.33 pts Question 18 The editors of a national automotive magazine recently studied 30 different automobiles sold in the United States with the intent of seeing whether they could develop a multiple regression model to explain the

1/10/24, 7:42 PM Chapter 15 Quiz: OSC 3440-090 Fall 2023 App of Business Stats https://utah.instructure.com/courses/891130/quizzes/3248145 15/23 A multiple regression is shown for a data set of yachts where the dependent variable is the price in thousands of dollars. Given this information, which is correct regarding the test of the overall model using the 0.10 level of significance? The overall model has significant ability to predict the price of a yacht because p - value = 0.163 is greater than 0.10 The overall model has significant ability to predict the price of a yacht because p - value = .001 is less than 0.10 The overall model does not have significant ability to predict the price of a yacht because p - value = .163 is greater than 0.10 The overall model does not have significant ability to predict the price of a yacht because p - value = .001 is less than 0.10 3.33 / 3.33 pts Question 22 The editors of a national automotive magazine recently studied 30 different automobiles sold in the United States with the intent of seeing

1/10/24, 7:42 PM Chapter 15 Quiz: OSC 3440-090 Fall 2023 App of Business Stats https://utah.instructure.com/courses/891130/quizzes/3248145 18/23 Based on this output and your understanding of multiple regression analysis, what percentage of variation in the dependent variable is explained by the regression model? About 37 percent Over 90 percent Approximately 82 percent None of the above 3.33 / 3.33 pts Question 25 The following multiple regression output was generated from a study in which two independent variables are included. The first independent variable (X1) is a quantitative variable measured on a continuous scale. The second variable (X2) is qualitative coded 0 if Yes, 1 if No.

1/10/24, 7:42 PM Chapter 15 Quiz: OSC 3440-090 Fall 2023 App of Business Stats https://utah.instructure.com/courses/891130/quizzes/3248145 21/23 The house value remains the same with or without a garage. A garage increases the house value by $5,400, holding all other independent variables constant. We need to include other dummy variables. A garage increases the house value by $5,400. 3.33 / 3.33 pts Question 28 A multiple regression is shown for a data set of yachts where the dependent variable is the price in thousands of dollars. Given this information, what is the null hypothesis for testing the overall model? H : β = β = β = β = 0 0 1 2 3 4 H : β = 0 0 0 H : β = β = β = β = β = 0 0 0 1 2 3 4 H : β = 0 0 1

1/10/24, 7:42 PM Chapter 15 Quiz: OSC 3440-090 Fall 2023 App of Business Stats https://utah.instructure.com/courses/891130/quizzes/3248145 22/23 3.33 / 3.33 pts Question 29 A study has recently been conducted by a major computer magazine publisher in which the objective was to develop a multiple regression model to explain the variation in price of personal computers. Three quantitative independent variables were used along with one qualitative variable. The qualitative variable was coded 1 if the computer included a monitor, 0 otherwise. The following computer printout shows the final output. Based on this information, and with a 0.05 level of significance, which of the following conclusions can be justified? There are substantial multicollinearity effects in this regression model. The only significant variable in the model at the .05 level of significance is Hard Drive Capacity. Removing the Monitor dummy variable would reduce the standard error of the estimate considerably.

1/10/24, 7:42 PM Chapter 15 Quiz: OSC 3440-090 Fall 2023 App of Business Stats https://utah.instructure.com/courses/891130/quizzes/3248145 23/23 Knowing whether the computer comes with a monitor or not is a significant factor in explaining the variation in price of the computer. 3.33 / 3.33 pts Question 30 Second - order polynomial models: always curve downward. measure interaction between variables. always curve upward. can curve upward or downward depending on the data. Quiz Score: 99.9 out of 99.9