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BUS 310, Homework #10, Fall 2017Instructor: Betsy McCallInstructions: Complete each problem on a separate worksheet in a single Excel file. Rename the separate worksheets with the respective problem number. You may have to copy and paste the datasets into your homework file first. Name the file with your last name, first initial, and HW #. Label each part of the question. When calculating statistics, label your outputs. Submit your completed file in Blackboard. If not significance level is specified, assume 5%.The file 310homework10data.xlsx, problem #1 includes data on 204 employees at the fictional company (Beta Technologies).Estimate a multiple regression equation to explain the variation in employee salaries at Beta Technologies using all of the potential explanatory variables.Using the regression output, determine which of the explanatory variables, if any, should be excluded from the regression equation. Justify your choices.Regardless of your answer to b, exclude the least significant variable (highest P-value) not including the constant and estimate the resulting equation. Would you conclude that this equation and the one from a are equally good? Explain.The file 310homework10data.xlsx in Problem #2 contains data on the top 40 golfers in 2008. This was the year when Tiger Woods won the U.S. Open in June, and then had year-ending surgery directly afterwards. Using all the golfers, run a regression of earnings per Round vs. the potential explanatory variables in Columns B-G. Then create a second data set that omits Tiger Woods and repeat the same regression on the smaller data set. Are the results about the same? Explain the effect, if any, of the Tiger Woods outlier in the regression.The file 310homework10data.xlsx in Problem #3 contains data from the owner of a restaurant in Bloomington, Indiana, recorded for the last 19 years. He has also recorded potentially relevant variables.Estimate a regression equation for sales as a function of population, advertising in the current year. Can you expect predictions of sales in future years to be very accurate if they are based on this regression equation? Explain.The company would like to predict sales in the next year (year 20). It doesn’t know what the population will be in year 20, so it assumes no change from year 19. Its planned advertising level for year 20 is $30,000. Find a prediction and a 95% prediction interval for sales in year 20. ................
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