Exam 17: Time Series Analysis and Forecasting

Weekly sales of the Weber Dicamatic food processor for the past ten weeks have been: a. Determine, on the basis of minimizing the mean square error, whether a three period or four period simple moving average model gives a better forecast for this problem. b. For each model, forecast sales for week 11.

Gradual shifting or movement of a time series to relatively higher or lower values over a longer period of time is called

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.

Four months ago, the Bank Drug Company introduced Jeffrey William brand designer bandages. Advertised using the slogan, "What the best dressed cuts are wearing", weekly sales for this period (in 1000's) have been as follows: a) Plot a graph of sales vs. weeks. Does linear trend appear reasonable? b) Assuming linear trend, forecast sales for weeks 17, 18, 19, and 20.

The sales volumes of CMM, Inc., a computer firm, for the past 8 years is given below. a.Develop a linear trend expression for the above time series. b.Forecast sales for period 9.

The yearly series below exhibits a long-term trend. Use the appropriate forecasting technique to produce forecasts for years 11 and 12.

Exhibit 17-3 Consider the following time series. -Refer to Exhibit 17-3. In which time period does the value of Y_i reach zero?

The trend pattern is easy to identify by using

Student enrollment at a university over the past six years is given below. a.Develop a linear trend expression for the above time series. b.Forecast enrollment for year 10.

The time series pattern that exists when the data fluctuate around a constant mean is the

The forecasting method that is appropriate when the time series has no significant trend, cyclical, or seasonal effect is

Exhibit 17-2 Consider the following time series. -Refer to Exhibit 17-2. The forecast for period 5 is

One measure of the accuracy of a forecasting model is the

Which of the following forecasting methods puts the least weight on the most recent time series value?

Exhibit 17-3 Consider the following time series. -Refer to Exhibit 17-3. The intercept, b₀, is

The objective of smoothing methods is to smooth out

The quarterly sales (in thousands of copies) for an educational software package 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 = 174 + 4 t (t represents time, where t = 1 for Quarter 1 of 2011 and t = 12 for Quarter 4 of 2013). Forecast sales for the first quarter of 2014 using the trend and seasonal indexes. Show all of your computations.

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

Based on the information shown below, develop forecasts for June using both a 2-period moving average model and an exponential smoothing model with $\alpha$ = 0.10. For the exponential smoothing model, assume the forecast for February was 800.

Exhibit 17-3 Consider the following time series. -The forecasting model that makes use of the "least squares" method is