Cheryl Johnson, the director of marketing for the Thingamajig Company, has collected data on the annual number of households in the state, the adjusted average annual household income, and Thingamajig's sales of widgets. She would like you to analyze these data for developing a forecast of future widget sales. Year 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 Number of Households 39.5 39.8 40.4 43.1 43.2 44.0 44.5 46.2 46.5 46.8 47.0 47.1 47.3 47.7 48.0 48.1 48.4 48.5 49.0 Average Household Income 34,000 34,600 41,000 38,000 39,000 42,000 44,000 49,000 46,000 51,000 48,000 47,000 50,000 51,000 53,000 54,000 55,000 53,000 57,000 Widgets Sold 5,500 5,600 5,900 5,800 6,100 6,900 6,300 7,300 6,700 6,900 7,200 7,100 7,100 7,400 7,600 7,900 7,300 8,000 8,500 Question #1 1. (A) In sheet Question #1,Perform a regression analysis on the above data to see if the population can be used to predict future sales. (B) Create a graph that shows the historical data, the regression line and 95% confidence interval lines. (C) Predict sales for the next three years based on the population projections listed below. (fill in the blanks below) Estimated Population 52.0 } Year 1999 2000 2001 52.1 52.3 Prediction (D) Is this a good representational model? Why or why not? (Answer): Question #2 2. (A) In sheet Question # 2 perform a regression analysis on the above data to see if household income can be used to predict future sales. (B) Create a graph that shows the historical data, the regression line and 95% confidence interval lines. (C) Predict sales for the next three years based on the income projections listed below. (fill in the blanks below) Estimated Income Year 1999 2000 2001 58,000 62,000 65,000 Prediction (D) Is this a good representational model? Why or why not? (Answer): Question #3 3. (A) In sheet Question # 3 perform a multiple regression analysis on the above data to see if household income and population can be used to predict future sales. (B) Predict sales for the next three years based on the income and population projections listed below. (fill in the blanks below) Estimated Income 58,000 62,000 B B 3 Year 0 1999 2000 2001 65,000 Estimated Population 52.0 52.1 = (C) Is this a good representational model? Why or why not? (Answer): 52.3 Prediction