BUS 327 Chapter 9
(T/F) A moving average (MA) method is most appropriate for data with major identifiable trends.
False
(T/F) In the context of causal forecasting models with multiple regression, an R-squared (R2) value of 0.70 means that 30 percent of the variation in the dependent variable is explained by the independent variable.
False
(T/F) Judgemental forecasting relies upon historical data in developing forecasts
False
(T/F)Call center service training is a preproduction service that requires forecasts to create value in a value chain.
False
(T/F) Forecasting is a key component in customer relationship management
True
(T/F) In the context of demand planning, customers' wants and needs define the customer benefit package.
True
__________is the difference between the observed value of the time series and the forecast. a. Forecast error b. Forecast consumption c. Forecast precision d. Forecast density
a. Forecast error
_____ are necessary to plan for facility expansion. a. Long-range forecasts b. Intermediate-range forecasts c. Make-to-order operations d. Make-to-stock operations
a. Long-range forecasts
In the context of a fairly stable time series with relatively little random variability, which of the following statements is true of single exponential smoothing (SES)? a. Values of the smoothing constant larger than 0.5 place more emphasis on recent data. b. Exponential smoothing models completely forget past data if the smoothing constant is strictly between 0 and 1. c. Typical values for the smoothing constant are in the range of 1 to 1.5. d. Values of the smoothing constant smaller than 0.1 allow a forecast to react faster to changing
a. Values of the smoothing constant larger than 0.5 place more emphasis on recent data.
A tracking signal provides a method for monitoring a forecast by quantifying ___________. a. bias b. throughput c. probability d. validity
a. bias
The mean absolute deviation (MAD) for the forecasts shown in the following table is: a. more than 10 but less than or equal to 20. b. more than 20 but less than or equal to 30. c. more than 30 but less than or equal to 40. d. more than 40 but less than or equal to 50.
a. more than 10 but less than or equal to 20.
A__________is the underlying pattern of growth or decline in a time series. a. trend b. planning horizon c. forecast error d. bias
a. trend
Alex, a manager at Symbic Inc., plotted the company's total energy costs of 1 billion dollars over the past 10 years on a chart. The chart suggested that the energy costs appear to be increasing in a fairly predictable linear fashion and that the energy costs are related to time by a linear function Y t =3+5t, where Y represents the estimate of the energy cost in year t. Given the equation, which of the following is the value of the intercept of the straight line that best fits the time series? a. 1 b. 3 c. 5 d. 10
b. 3
_____ are needed to plan workforce levels, allocate budgets among divisions, and schedule jobs and resources. a. Make-to-order operations b. Intermediate-range forecasts c. Short-range forecasts d. Make-to-stock operations
b. Intermediate-range forecasts
__________is a method for building a statistical model that defines a relationship between a single dependent variable and one or more independent variables, all of which are numerical. a. The Delphi method b. Regression analysis c. Judgmental forecasting d. The Cooke method
b. Regression analysis
__________is a forecasting technique that uses a weighted average of past time-series values to forecast the value of the time series in the next period. a. A moving average forecast b. Single exponential smoothing c. A grassroots forecast d. Regression analysis
b. Single exponential smoothing
__________is based on the assumption that the future will be an extrapolation of the past. a. Judgmental forecasting b. Statistical forecasting c. The Delphi method d. The Cooke method
b. Statistical forecasting
The following table shows the data for the sales of tennis rackets at a store for 4 consecutive months. Find the forecast error in month 4 using a 3-month moving average. a. The forecast error in month 4 is less than or equal to 5. b. The forecast error in month 4 is more than 5 but less than or equal to 10. c. The forecast error in month 4 is more than 10 but less than or equal to 15. d. The forecast error in month 4 is more than 15.
b. The forecast error in month 4 is more than 5 but less than or equal to 10.
18. In the context of forecasting, the term__________refers to the tendency of forecasts to consistently be larger or smaller than the actual values of the time series. a. trend b. bias c. fad d. variability
b. bias
In the context of data patterns and variations in a time series, _____ are characterized by repeatable periods of ups and downs over short periods of time. a. random variations b. seasonal patterns c. cyclical patterns d. irregular variations
b. seasonal patterns
_____ is a common approach to gather data for judgmental forecasts. a. A moving average model b. Regression analysis c. A survey questionnaire d. Single exponential smoothing
c. A survey questionnaire
_____ are used by operations managers to plan production schedules and assign workers to jobs. a. Balanced scorecards b. Intermediate-range forecasts c. Short-range forecasts d. Credit scorecards
c. Short-range forecasts
The following table shows the sales data of server computers of Ziffcore Inc. for the past 5 years. The management plotted the data on a chart. The chart suggested that the sales appear to be increasing in a fairly predictable linear fashion and that the sales are related to time by a linear function Y t =240+340t. Using simple linear regression, calculate the forecast for sales in year 6. a. The forecast for sales in year 6 is more than 1800 but less than or equal to 2000. b. The forecast for sales in year 6 is more than 2000 but less than or equal to 2200. c. The forecast for sales in year 6 is more than 2200 but less than or equal to 2400. d. The forecast for sales in year 6 is more than 2400 but less than or equal to 2600.
c. The forecast for sales in year 6 is more than 2200 but less than or equal to 2400.
The following table shows the sales data of a particular model of a DVD player. If the forecast sales for May is 36.25, calculate the sales forecast for July using the simple exponential smoothing (SES) model with a smoothing constant of 0.40. a. The sales forecast for July is more than 30 but less than or equal to 35. b. The sales forecast for July is more than 35 but less than or equal to 40. c. The sales forecast for July is more than 40 but less than or equal to 50. d. The sales forecast for July is more than 50 but less than or equal to 55.
c. The sales forecast for July is more than 40 but less than or equal to 50.
In the context of data patterns in a time series, regular patterns in a data series that take place over long periods of time are called _____. a. orthographic patterns b. seasonal patterns c. cyclical patterns d. parallel patterns
c. cyclical patterns
Moving average (MA) methods work best when: a. a long planning horizon is involved. b. a cyclical pattern is observed in a time series. c. demand is relatively stable and consistent. d. there is a major trend in a time series.
c. demand is relatively stable and consistent.
If the time series in an exponential smoothing model exhibits a negative trend, the _____. a. mean square error will be negative b. value of smoothing constant will either be less than zero or greater than one c. forecast will overshoot the actual values d. future forecasts will rely solely upon expertise of people in developing forecasts
c. forecast will overshoot the actual values
In the context of data patterns in a time series, a(n) _____ is a one-time variation that is explainable. a. cyclical variation b. random variation c. irregular variation d. seasonal variation
c. irregular variation
When no historical data are available, _____ is the sole basis for predicting future demands. a. Statistical forecasting b. regression analysis c. judgmental forecasting d. exponential smoothing
c. judgmental forecasting
The mean absolute percentage error (MAPE) for the forecasts shown in the following table is: a. less than or equal to 5 percent. b. more than 5 percent but less than or equal to 10 percent. c. more than 10 percent but less than or equal to 15 percent. d. more than 15 percent.
c. more than 10 percent but less than or equal to 15 percent.
In the Delphi method of judgmental forecasting, _____. a. predictions are based on the assumption that the future will be an extrapolation of the past b. predictions are based on one or more independent variables, all of which are numerical c. people from outside an organization are not eligible to make predictions d. experts are not consulted as a group to make predictions
d. experts are not consulted as a group to make predictions
In the context of forecasting errors, _____ eliminates the measurement scale factor. a. normalized mean signed deviation b. mean absolute deviation c. normalized root mean square error d. mean absolute percentage error
d. mean absolute percentage error
An exponential smoothing model must have a smoothing constant (α) _____ to be roughly equivalent to a moving average model with a seven-month moving average. a. less than or equal to 0.10 b. more than 0.10 but less than or equal to 0.15 c. more than 0.15 but less than or equal to 0.20 d. more than 0.20
d. more than 0.20
The mean square error (MSE) for the forecasts shown in the following table is: a. more than 250 but less than or equal to 300. b. more than 300 but less than or equal to 350 c. more than 350 but less than or equal to 400. d. more than 400 but less than or equal to 450.
d. more than 400 but less than or equal to 450.