Exam 16: Time Series and Forecasting

i. In the ratio-to-moving-average procedure, using the median or modified mean eliminates trend) ii. A typical seasonal index of 103.7 for January indicates that sales for January are below the annual average) iii. The total of the four typical quarterly indexes should equal 100.0.

A linear trend equation is used to represent time series values when the dependent data are changing by equal?

i. A typical monthly seasonal index of 107.0 indicates that sales (or whatever the variable is) are 107 percent above the annual average) ii. The ratio-to-moving average method removes the time series trend component, resulting in 12 numbers that are called specific seasonals. iii. The total of the four typical quarterly indexes should equal 100.0.

Teton Village contains shops, restaurants and motels. They have two peak seasons, - winter for skiing, and summer, for tourists visiting nearby parks. The specific seasonal with respect to the total sales volume for recent years are: Using the seasonal indexes below, explain the typical index for the fall season.

If the exports ($ millions) for the period 1997 through 2001 were $878, $892, $864, $870 and $912 respectively, what are these values called?

A logarithmic straight-line trend equation should be used for forecasts when the time series is increasing by?

What is a disadvantage of estimating a trend line equation by "eye-balling" the best fitting line to a scatter diagram?

i. In the linear trend equation, the letter "b" is the average change in t for each change of one unit (either increase or decrease) in y. ii. The least squares method of computing the equation for a straight line going through the data of interest gives the "best fitting" line. iii. A straight-line trend equation is used to represent the time series when it is believed that the data is increasing (or decreasing) by equal amounts, on the average, from one period to another.

i. In the ratio-to-moving-average procedure, using the median or modified mean eliminates trend) ii. In the final step, using the ratio-to-moving-average method on quarterly data, the total of the modified means should theoretically be equal to 400 because the average of should be 100. iii. Seasonal variation is quite common in the retail and wholesale industries.

i. For a quarterly time series, the initial step, using the ratio-to-moving average method, is to remove the seasonal components from the time series using a 3-month centered moving average) ii. In the ratio-to-moving-average procedure, using the median or modified mean eliminates trend) iii. In the final step, using the ratio-to-moving-average method on quarterly data, the total of the modified means should theoretically be equal to 400 because the average of should be 100.

i. A forecast is considered necessary in order to have the raw materials, production facilities, and staff available to meet estimated future demands. Ii) One component of a time series is the secular trend that is the smooth movement of a series over a short period of time, such as a few months or quarters. Iii) Many business and economic time series have a recurring seasonal pattern.

Listed below is the net sales in $ million for Home Depot Inc., and its subsidiaries from 1994 to 2003. Using the printout below, what are the estimated sales for 2004?

What time series component was exemplified during the 1980's when the World economy enjoyed a period of prosperity?

i. A time series is a collection of data recorded over a period of time, usually monthly, quarterly, or yearly. Ii) Long-term forecasts are usually from one year to more than 10 years into the future. Iii) A forecast is considered necessary in order to have the raw materials, production facilities, and staff available to meet estimated future demands.

i. Long-term forecasts are usually from one year to more than 10 years into the future. ii. A forecast is considered necessary in order to have the raw materials, production facilities, and staff available to meet estimated future demands. Iii) One component of a time series is the secular trend that is the smooth movement of a series over a short period of time, such as a few months or quarters.

Given the trend equation ŷ = 25 + 0.6t (t = 0 in 1996), what would be the forecast value for 2000?

In the linear trend equation, how is the average change in the dependent variable represented for every unit change in time?

i. The cyclical component of a time series is described in terms relative to the seasonal index. ii. The irregular component of a time series is the easiest to measure. Iii) The ratio-to-moving average method removes the time series trend component, resulting in 12 numbers that are called specific seasonals.

How can you describe the moving average method?

i. A typical monthly seasonal index of 107.0 indicates that sales (or whatever the variable is) are 107 percent above the annual average. ii. Each typical seasonal index is a percent with the average for the year equal to 100. Iii) The ratio-to-moving-average method eliminates the seasonal, cyclical and irregular components from the original data (y).t6 The trend component of a time series is obtained my minimizing the sum of the squares of the errors.