Exam 16: Time-Series Forecasting

SCENARIO 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 Scenario 16-3, if this series is smoothed using exponential smoothing with a smoothing constant of 1/3, what would be the third value?

SCENARIO 16-4 The number of cases of merlot wine sold by a Paso Robles winery in an 8-year period follows. -Referring to Scenario 16-4, exponential smoothing with a weight or smoothing constant of 0.2 will be used to forecast wine sales.The forecast for 2013 is __________.

SCENARIO 16-13 Given below is the monthly time series data for U.S.retail sales of building materials over a specific year. The results of the linear trend, quadratic trend, exponential trend, first-order autoregressive, second-order autoregressive and third-order autoregressive model are presented below in which the coded month for the month is 0: Below is the residual plot of the various models: -Referring to Scenario 16-13, what is your forecast for the month using the third-order autoregressive model?

Microsoft Excel was used to obtain the following quadratic trend equation: Sales = 100 - 10X + . The data used was from 2004 through 2013 coded 0 to 9.The forecast for 2014 is __________.

SCENARIO 16-13 Given below is the monthly time series data for U.S.retail sales of building materials over a specific year. The results of the linear trend, quadratic trend, exponential trend, first-order autoregressive, second-order autoregressive and third-order autoregressive model are presented below in which the coded month for the month is 0: Below is the residual plot of the various models: -Referring to Scenario 16-13, you can conclude that the third-order autoregressive model is appropriate at the 5% level of significance.

SCENARIO 16-9 Given below are EXCEL outputs for various estimated autoregressive models for a company's real operating revenues (in billions of dollars)from 1989 to 2012.From the data, you also know that the real operating revenues for 2010, 2011, and 2012 are 11.7909, 11.7757 and 11.5537, respectively. -Referring to Scenario 16-9, if one decides to use the Third-Order Autoregressive model, what will the predicted real operating revenue for the company be in 2014?

SCENARIO 16-9 Given below are EXCEL outputs for various estimated autoregressive models for a company's real operating revenues (in billions of dollars)from 1989 to 2012.From the data, you also know that the real operating revenues for 2010, 2011, and 2012 are 11.7909, 11.7757 and 11.5537, respectively. -Referring to Scenario 16-9, if one decides to use the Third-Order Autoregressive model, what will the predicted real operating revenue for the company be in 2013?

SCENARIO 16-4 The number of cases of merlot wine sold by a Paso Robles winery in an 8-year period follows. -Referring to Scenario 16-4, a centered 3-year moving average is to be constructed for the wine sales.The moving average for 2009 is __________.

SCENARIO 16-11 The manager of a health club has recorded mean attendance in newly introduced step classes over the last 15 months: 32.1, 39.5, 40.3, 46.0, 65.2, 73.1, 83.7, 106.8, 118.0, 133.1, 163.3, 182.8, 205.6, 249.1, and 263.5.She then used Microsoft Excel to obtain the following partial output for both a first- and second-order autoregressive model. SUMMARY OUTPUT - Order Model SUMMARY OUTPUT - 1 Order Model -Referring to Scenario 16-11, using the second-order model, the forecast of mean attendance for month 16 is __________.

SCENARIO 16-2 The monthly advertising expenditures of a department store chain (in $1,000,000s)were collected over the last decade.The last 14 months of this time series follows: -Referring to Scenario 16-2, set up a scatter plot (i.e., time-series plot)with months on the horizontal X-axis.

SCENARIO 16-10 Business closures in a city in the western U.S.from 2007 to 2012 were: Microsoft Excel was used to fit both first-order and second-order autoregressive models, resulting in the following partial outputs: -Referring to Scenario 16-10, the values of the MAD for the two models indicate that the first-order model should be used for forecasting.

The fairly regular fluctuations that occur within each year would be contained in the _________________ component.

SCENARIO 16-6 The president of a chain of department stores believes that her stores' total sales have been showing a linear trend since 1993.She uses Microsoft Excel to obtain the partial output below. The dependent variable is sales (in millions of dollars), while the independent variable is coded years, where 1993 is coded as 0, 1994 is coded as 1, etc. SUMMARY OUTPUT -Referring to Scenario 16-6, the forecast for sales (in millions of dollars)in 2013 is __________.

SCENARIO 16-4 The number of cases of merlot wine sold by a Paso Robles winery in an 8-year period follows. -Referring to Scenario 16-4, exponential smoothing with a weight or smoothing constant of 0.4 will be used to smooth the wine sales.The value of , the smoothed value for 2006 is __________.

SCENARIO 16-10 Business closures in a city in the western U.S.from 2007 to 2012 were: Microsoft Excel was used to fit both first-order and second-order autoregressive models, resulting in the following partial outputs: -Referring to Scenario 16-10, the value of the MAD for the second-order autoregressive model is ________.

SCENARIO 16-12 A local store developed a multiplicative time-series model to forecast its revenues in future quarters, using quarterly data on its revenues during the 5-year period from 2009 to 2013.The following is the resulting regression equation: where is the estimated number of contracts in a quarter. X is the coded quarterly value with X = 0 in the first quarter of 2008. is a dummy variable equal to 1 in the first quarter of a year and 0 otherwise. is a dummy variable equal to 1 in the second quarter of a year and 0 otherwise. is a dummy variable equal to 1 in the third quarter of a year and 0 otherwise. -Referring to Scenario 16-12, the best interpretation of the coefficient of X (0.012)in the regression equation is:

SCENARIO 16-12 A local store developed a multiplicative time-series model to forecast its revenues in future quarters, using quarterly data on its revenues during the 5-year period from 2009 to 2013.The following is the resulting regression equation: where is the estimated number of contracts in a quarter. X is the coded quarterly value with X = 0 in the first quarter of 2008. is a dummy variable equal to 1 in the first quarter of a year and 0 otherwise. is a dummy variable equal to 1 in the second quarter of a year and 0 otherwise. is a dummy variable equal to 1 in the third quarter of a year and 0 otherwise. -Referring to Scenario 16-12, using the regression equation, what is the forecast for the revenues in the first quarter of 2016?

SCENARIO 16-14 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 2011 to 2013.The following is the resulting regression equation: where is the estimated number of contracts in a quarter. X is the coded quarterly value with X = 0 in the first quarter of 2011. is a dummy variable equal to 1 in the first quarter of a year and 0 otherwise. Q is a dummy variable equal to 1 in the second quarter of a year and 0 otherwise. is a dummy variable equal to 1 in the third quarter of a year and 0 otherwise. -Referring to Scenario 16-14, the best interpretation of the coefficient of Q (0.617)in the regression equation is:

SCENARIO 16-13 Given below is the monthly time series data for U.S.retail sales of building materials over a specific year. The results of the linear trend, quadratic trend, exponential trend, first-order autoregressive, second-order autoregressive and third-order autoregressive model are presented below in which the coded month for the month is 0: Below is the residual plot of the various models: -Referring to Scenario 16-13, if a five-month moving average is used to smooth this series, what would be the last calculated value?

SCENARIO 16-7 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 1999.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 1999 is coded as 0, 2000 is coded as 1, etc. SUMMARY OUTPUT -Referring to Scenario 16-7, the fitted trend value for 1999 is __________.