Average Daily TV Viewing Time Per U.S. Household
Average Daily TV Viewing Time Per U.S. Household
Year Code (t) Total Minutes
Year Code (t) Total Minutes
1950 1 275
1950 1 275
1955 2 291
1955 2 291
1960 3 306
1960 3 306
1965 4 329
1965 4 329
1970 5 356
1970 5 356
1975 6 367
1975 6 367
1980 7 396
1980 7 396
1985 8 430
1985 8 430
1990 9 413
1990 9 413
1995 10 437
1995 10 437
2000 11 455
2005 12 ?
2005 12 ?
(a) Plot the total minutes of TV viewing time per household.
(a) Plot the total minutes of TV viewing time per household.
(b) Describe the trend (if any) and discuss possible causes.
(b) Describe the trend (if any) and discuss possible causes.
(c) Fit a linear trend to the data.
(c) Fit a linear trend to the data.
(d) Would this model give reasonable forecasts? Would another trend model be better? Explain. (e) Make a forecast for 2005. Note: Time is in 5-year increments, so use t = 12 for the 2005 forecast.
(d) Would this model give reasonable forecasts? Would another trend model be better? Explain. (e) Make a forecast for 2005. Note: Time is in 5-year increments, so use t = 12 for the 2005 forecast.
Part 2. Given the following data:
Asian and European share of U.S light truck sales. 1990-2003
Year Percent Year Percent
1990 16.4 1997 15.4
1991 17.1 1998 16.2
1992 14.3 1999 18.4
1993 13.7 2000 21.2
1994 14.2 2001 23.1
1995 13.6 2002 23.9
1996 13.6 2003 25.6
(a) Plot the market-share data. (b) Describe the trend (if any) and discuss possible causes. (c) Fit three trends (linear, exponential, quadratic). (d) Which trend model is best, and why? If none is satisfactory, explain. (e) Make a forecast for 2004 by using a trend model of your choice or a judgment forecast.
