Exam 18: Forecasting

The trend component is easy to identify by using

The following information has been collected on the sales of greeting cards for the past 6 weeks. a.Produce exponential smoothing forecasts for the series using a smoothing constant of .2. b.Compute the mean square error for the forecasts produced with a smoothing constant of .2. c.What is the forecast of sales for week 7? d.Is a smoothing constant of .2 or .3 better for the sales data? Explain.

Consider the following time series. a.Develop a linear trend equation for this time series. b.What is the forecast for t = 17?

The model that assumes that the actual time series value is the product of its components is the

One measure of the accuracy of a forecasting model is

A component of the time series model that results in the multi-period above-trend and below-trend behavior of a time series is

Below you are given the first two values of a time series.You are also given the first two values of the exponential smoothing forecast. If the smoothing constant equals .3,then the exponential smoothing forecast for time period three is

For the following time series,you are given the moving average forecast. The mean squared error equals

Below you are given information on John's income for the past 7 years. a.Use regression analysis to obtain an expression for the linear trend component. b.Forecast John's income for the next 5 years.

A group of observations measured at successive time intervals is known as

The following data show the quarterly sales of Amazing Graphics,Inc.for the years 6 through 8. a.Compute the four-quarter moving average values for the above time series. b.Compute the seasonal factors for the four quarters. c.Use the seasonal factors developed in Part b to adjust the forecast for the effect of season for year 6.

You are given the following information on the seasonal-irregular component values for a quarterly time series: The seasonal index for Quarter 1 is

The following time series shows the number of units of a particular product sold over the past six months. a.Compute a 3-month moving average (centered)for the above time series. b.Compute the mean square error (MSE)for the 3-month moving average. c.Use $\alpha$ = 0.2 to compute the exponential smoothing values for the time series. d.Forecast the sales volume for month 7.

Actual sales of a company (in millions of dollars)for January through April are shown below. a.Use= 0.3 to compute the exponential smoothing values for sales.Compute MSE and forecast sales for May.Show all of your computations from February through May. b.Use= 0.1 to compute the exponential smoothing values for sales.Compute MSE and forecast sales for May.Show all of your computations from February through May. c.Based on MSE,whichprovides a better forecast? Explain why?

Exhibit 18-2 Consider the following time series. -Refer to Exhibit 18-2.The forecast for period 5 is

The quarterly sales of a company (in millions of dollars)over the past three years are given in the following table. a.Compute the four seasonal factors (Seasonal Indexes).Show all of your computations. b.The trend for these data is Trend = 20.82 + 0.336 t (t represents time,where t=1 for Quarter 1 of 2007 and t=12 for Quarter 4 of 2009).Forecast sales for the first quarter of 2010 using the trend only.Show all of your computations. c.Forecast sales for the first quarter of 2010 using the trend and seasonal indexes and write your answer below.Show all of your computations.

If data for a time series analysis is collected on an annual basis only,which component may be ignored?

In the linear trend equation,T = b₀ + b₁t,b₁ represents the

Which of the following is not present in a time series?

Below you are given some values of a time series consisting of 26 time periods. The estimated regression equation for these data is Y_t = 16.23 + .52Y_t-1 + .37Y_t-2 The forecasted value for time period 27 is