Regression Statistics & Forecasting Method Excel Questions
ANSWER
Exercise 28 (Multiple Regression): a. Using Excel, do a multiple regression analysis where the dependent variable is the current wage, and the independent factors are the starting salary, prior experience, and total years of schooling. You will receive the regression equation from the output.
b. You should look at the t-values for each independent variable in the regression output to determine which model best fits the data using the t-value criterion. One by one, eliminate variables with high p-values (usually >0.05) until the last variable has a low p-value.
As part of Exercise 8 (Moving Averages), a. Make a spreadsheet with the DJIA and each stock’s two- and three-period moving averages, and b. Project the stock prices.
b. For the two- and three-period moving averages, compute the mean absolute deviation (MAD), mean squared error (MSE), and mean absolute percentage error (MAPE). To find out which moving average period is best for forecasting, compare these parameters.
Exercise 5 (Linear Optimization): a. Decision Variables: Let x and y represent the minutes allotted to radio and television advertising.
Maximize exposure (350x + 800y) while considering the financial constraints.
Limitations:
400x + 2000y ≤ 25000 is the budget constraint.
y > 0.75(x + y) (at least 75% of TV time) is the allocation constraint.
b. Put these calculations into a spreadsheet and use Solver to determine the best answer. The solver will supply the values of x and y that optimize exposure within the limitations of budget and allocation.
Exercise 12: Making Decisions in the Face of Uncertainty
Aggressive Strategy: Select the option (Wisconsin or Carmel) with the lowest cost for each scenario.
a. Conservative Strategy: For each scenario, pick the choice (Wisconsin or Carmel) with the highest cost.
c. Opportunity-Loss Strategy: Determine which choice will minimize the difference between the best and second-best options for each situation.
Exercise 10 (Expected Value Decision):
- Multiply the probability of each situation by the associated cost for each approach (aggressive, conservative, opportunity-loss) to determine the expected cost.
- Add up these numbers.
- Select the plan whose projected cost is the lowest.
QUESTION
Description
Based on Evans (2020) Chapters 8, 9, 13, and 16 end-of-chapter exercises:
- Chapter 8 #28;
- Chapter 9 # 8;
- Chapter 13 #5, 12;
- Chapter 16# 3, 10.
INSTRUCTION:
Complete the Analysis using Excel.
- 28. The Excel file Salary Data provides information on current salary, beginning salary, previous experience (in months) when hired, and total years of education for a sample of 100 employees in a firm. a. Find the multiple regression model for predicting current salary as a function of the other variables. b. Find the best model for predicting current salary using the t-value criterion.
- 8. The Excel file Closing Stock Prices provides data for four stocks and the Dow Jones Industrial Average over a one-month period. a. Develop a spreadsheet for forecasting each of the stock prices and the DJIA using a simple twoperiod and three-period moving average. b. Compute MAD, MSE, and MAPE and determine whether two or three moving average periods is better.
- 5) A brand manager for ColPal Products must determine how much time to allocate between radio and television advertising during the next month. Market research has provided estimates of the audience exposure for each minute of advertising in each medium, which it would like to maximize. Costs per minute of advertising are also known, and the manager has a limited budget of $25,000. The manager has decided that because television ads have been found to be much more effective than radio ads, at least 75% of the time should be allocated to television. Suppose that we have the following data: Type of Ad Exposure/Minute Cost/Minute Radio 350 $400 TV 800 $2,000 a. Identify the decision variables, objective function, and constraints in simple verbal expressions. b. Mathematically formulate a linear optimization model.
- 12. Implement the linear optimization model that you developed for ColPal Products in Problem 5 on a spreadsheet and use Solver to find an optimal solution. Interpret the Solver Answer Report, identify the binding constraints, and verify the values of the slack variables by substituting the optimal solution into the model constraints.
- *3. The DoorCo Corporation is a leading manufacturer of garage doors. All doors are manufactured in their plant in Carmel, Indiana, and shipped to distribution centers or major customers. DoorCo recently acquired another manufacturer of garage doors, Wisconsin Door, and is considering moving its wood door operations to the Wisconsin plant. Key considerations in this decision are the transportation, labor, and production costs at the two plants. Complicating matters is the fact that marketing is predicting a decline in the demand for wood doors. The company developed three scenarios: a. Demand falls slightly, with no noticeable effect on production. b. Demand and production decline 20%. c. Demand and production decline 40%. The following table shows the total costs under each decision and scenario. Slight Decline 20% Decline 40% Decline Stay in Carmel $1,000,000 $800,000 $840,000 Move to Wisconsin $1,100,000 $950,000 $750,000 What decision should DoorCo make using each of the following strategies? a. aggressive strategy b. conservative strategy c. opportunity-loss strategy.
- 10. For the DoorCo Corporation decision in Problem 3, suppose that the probabilities of the three scenarios are estimated to be 0.15, 0.40, and 0.45, respectively. Find the best expected value decision.