Exam 16: Time-Series Analysis and Index Numbers

TABLE 16-13 A local store developed a multiplicative time-series model to forecast its revenues in future quarters, using quarterly data on its revenues during the 4-year period from 2005 to 2009. The following is the resulting regression equation: -Referring to Table 16-13, to obtain a forecast for the fourth quarter of 2006 using the model, which of the following sets of values should be used in the regression equation?

TABLE 16-3 The following table contains the number of complaints received in a department store for the first 6 months of last year. -Referring to Table 16-3, if a three-month moving average is used to smooth this series, how many values would it have?

The principle of parsimony indicates that the simplest model that gets the job done adequately should be used.

If a time series does not exhibit a long-term trend, the method of exponential smoothing may be used to obtain short-term predictions about the future.

The method of least squares may be used to estimate both linear and curvilinear trends.

TABLE 16-6 The number of cases of merlot wine sold by a Paso Robles winery in an 8-year period follows. -Referring to Table 16-6, exponential smoothing with a weight or smoothing constant of 0.4 will be used to smooth the wine sales. The value of E₂, the smoothed value for 2002 is ________.

TABLE 16-9 The executive vice-president of a drug manufacturing firm believes that the demand for the firm's most popular drug has been evidencing an exponential trend since 1995. She uses Microsoft Excel to obtain the partial output below. The dependent variable is the log base 10 of the demand for the drug, while the independent variable is years, where 1995 is coded as 0, 1996 is coded as 1, etc. SUMMARY OUTPUT Regression Statistics -Referring to Table 16-9, the fitted trend value for 1995 is ________.

The effect of an unpredictable, rare event will be contained in the ________ component.

TABLE 16-5 A contractor developed a multiplicative time-series model to forecast the number of contracts in future quarters, using quarterly data on number of contracts during the 3-year period from 2006 to 2008. The following is the resulting regression equation: -Referring to Table 16-5, to obtain a forecast for the first quarter of 2009 using the model, which of the following sets of values should be used in the regression equation?

When using the exponentially weighted moving average for purposes of forecasting rather than smoothing,

Which of the following statements about the method of exponential smoothing is not true?

The method of moving averages is used

TABLE 16-7 The number of passengers arriving at San Francisco on the Amtrak cross-country express on 6 successive Mondays were: 60, 72, 96, 84, 36, and 48. -Referring to Table 16-7, the number of arrivals will be smoothed with a 5-term moving average. The last smoothed value will be ________.

TABLE 16-11 Business closures in Laramie, Wyoming from 2003 to 2008 were: Microsoft Excel was used to fit both first-order and second-order autoregressive models, resulting in the following partial outputs: SUMMARY OUTPUT - 2^nd Order Model SUMMARY OUTPUT - 1^st Order Model -Referring to Table 16-11, the residuals for the second-order autoregressive model are ________, ________, ________, and ________.

TABLE 16-7 The number of passengers arriving at San Francisco on the Amtrak cross-country express on 6 successive Mondays were: 60, 72, 96, 84, 36, and 48. -Referring to Table 16.7, exponentially smooth the number of arrivals using a smoothing constant of 0.1.

TABLE 16-6 The number of cases of merlot wine sold by a Paso Robles winery in an 8-year period follows. -Referring to Table 16-6, a centered 3-year moving average is to be constructed for the wine sales. The result of this process will lead to a total of ________ moving averages.

To assess the adequacy of a forecasting model, one measure that is often used is

TABLE 16-5 A contractor developed a multiplicative time-series model to forecast the number of contracts in future quarters, using quarterly data on number of contracts during the 3-year period from 2006 to 2008. The following is the resulting regression equation: -Referring to Table 16-5, the best interpretation of the coefficient of Q₃ (0.617) in the regression equation is:

MAD is the summation of the residuals divided by the sample size.

TABLE 16-7 The number of passengers arriving at San Francisco on the Amtrak cross-country express on 6 successive Mondays were: 60, 72, 96, 84, 36, and 48. -Referring to Table 16-7, exponentially smooth the number of arrivals using a smoothing constant of 0.25.