03 Chapter - Forecasting
Chapter 03 Forecasting
True / False Questions 1. Forecasting techniques generally assume an existing causal system that will continue to exist in the future. TRUE
Difficulty: Medium TLO: 2 Taxonomy: Knowledge
2. For new products in a strong growth mode, a low alpha will minimize forecast errors when using exponential smoothing techniques. FALSE
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3. Once accepted by managers, forecasts should be held firm regardless of new input since many plans have been made using the original forecast. FALSE
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4. Forecasts for groups of items tend to be less accurate than forecasts for individual items because forecasts for individual items don't include as many influencing factors. FALSE
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5. Forecasts help managers plan both the system itself and provide valuable information for using the system. TRUE
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6. Organizations that are capable of responding quickly to changing requirements can use a shorter forecast horizon and therefore benefit from more accurate forecasts. TRUE
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7. When new products or services are introduced, focus forecasting models are an attractive option. FALSE
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8. The purpose of the forecast should be established first so that the level of detail, amount of resources, and accuracy level can be understood. TRUE
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9. Forecasts based on time series (historical) data are referred to as associative forecasts. TRUE
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10. Time series techniques involve identification of explanatory variables that can be used to predict future demand. FALSE
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11. A consumer survey is an easy and sure way to obtain accurate input from future customers since most people enjoy participating in surveys. FALSE
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12. The Delphi approach involves the use of a series of questionnaires to achieve a consensus forecast. TRUE
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13. Exponential smoothing adds a percentage (called alpha) of last period's forecast to estimate next period's demand. FALSE
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14. The shorter the forecast period, the more accurately the forecasts tend to track what actually happens. TRUE
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15. Forecasting techniques that are based on time series data assume that future values of the series will duplicate past values. FALSE
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16. Trend adjusted exponential smoothing uses double smoothing to add twice the forecast error to last periods actual. FALSE
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17. Forecasts based on an average tend to exhibit less variability than the original data. TRUE
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18. The naive approach to forecasting requires a linear trend line. FALSE
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19. The naive forecast is limited in its application to series that reflect no trend or seasonality. FALSE
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20. The naive forecast can serve as a quick and easy standard of comparison against which to judge the cost and accuracy of other techniques. TRUE
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21. A moving average forecast tends to be more responsive to changes in the data series when more data points are included in the average. FALSE
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22. In order to update a moving average forecast, the values of each data point in the average must be known. TRUE
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23. Forecasts of future demand are used by operations people to plan capacity. TRUE
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24. An advantage of a weighted moving average is that recent actual results can be given more importance than what occurred a while ago. TRUE
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25. Exponential smoothing is a form of weighted averaging. TRUE
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26. A smoothing constant of .1 will cause an exponential smoothing forecast to react more quickly to a sudden change than a smoothing constant value of .3. FALSE
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27. The T in the model TAF = S+T represents the time dimension (which is usually expressed in weeks or months). FALSE
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28. Trend adjusted exponential smoothing requires selection of two smoothing constants. TRUE
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29. An advantage of "trend adjusted exponential smoothing" over the "linear trend equation" is its ability to adjust over time to changes in the trend. TRUE
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30. A seasonal relative (or seasonal indexes) is expressed as a percentage of average or trend. TRUE
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31. In order to compute seasonal relatives, the trend of past data must be computed or known which means that for brand new products this approach can't be used. TRUE
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32. Removing the seasonal component from a data series (de-seasonalizing) can be accomplished by dividing each data point by its appropriate seasonal relative. TRUE
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33. If a pattern appears when a dependent variable is plotted against time, one should use time series analysis instead of regression analysis. TRUE
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34. Curvilinear and multiple regression procedures permit us to extend associative models to relationships that are non-linear or involve more than one predictor variable. TRUE
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35. The sample standard deviation of forecast error, is equal to the square root of MSE. TRUE
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36. Correlation measures the strength and direction of a relationship between variables. TRUE
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37. MAD is equal to the square root of MSE which is why we calculate the easier MSE and then calculate the more difficult MAD. FALSE
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38. In exponential smoothing, an alpha of 1.0 will generate the same forecast that a nave forecast would yield. TRUE
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39. A forecast method is generally deemed to perform adequately when the errors exhibit an identifiable pattern. FALSE
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40. A control chart involves setting action limits for cumulative forecast error. FALSE
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41. A tracking signal focuses on the ratio of cumulative forecast error to the corresponding value of MAD. TRUE
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42. The use of a control chart assumes that errors are normally distributed about a mean of zero. TRUE
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43. Bias exists when forecasts tend to be greater or less than the actual values of time series. TRUE
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44. Bias is measured by the cumulative sum of forecast errors. TRUE
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45. Seasonal relatives can be used to de-seasonalize data or incorporate seasonality in a forecast. TRUE
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46. The best forecast is not necessarily the most accurate. TRUE
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47. A proactive approach to forecasting views forecasts as probable descriptions of future demand, and requires action to be taken to meet that demand. FALSE
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48. Simple linear regression applies to linear relationships with no more than three independent variables. FALSE
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49. An important goal of forecasting is to minimize the average forecast error. FALSE
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50. Forecasting techniques such as moving averages, exponential smoothing, and the naive approach all represent smoothed (averaged) values of time series data. FALSE
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51. In exponential smoothing, an alpha of .30 will cause a forecast to react more quickly to a large error than will an alpha of .20. TRUE
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Multiple Choice Questions 52. Forecasts based on judgment and opinion don't include A. executive opinion B. salesperson opinion C. second opinions D. customer surveys E. Delphi methods
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53. In business, forecasts are the basis for: A. capacity planning B. budgeting C. sales planning D. production planning E. all of the above
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54. Which of the following features would not generally be considered common to all forecasts? A. Assumption of a stable underlying causal system B. Actual results will differ somewhat from predicted values. C. Historical data is available on which to base the forecast. D. Forecasts for groups of items tend to be more accurate than forecasts for individual items. E. Accuracy decreases as the time horizon increases.
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55. Which of the following is not a step in the forecasting process? A. determine the purpose and level of detail required B. eliminate all assumptions C. establish a time horizon D. select a forecasting model E. monitor the forecast
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56. Minimizing the sum of the squared deviations around the line is called: A. mean squared error technique B. mean absolute deviation C. double smoothing D. least squares line E. predictor regression
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57. The two general approaches to forecasting are: A. mathematical and statistical B. qualitative and quantitative C. judgmental and qualitative D. historical and associative E. precise and approximation
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58. Which of the following is not a type of judgmental forecasting? A. executive opinions B. sales force opinions C. consumer surveys D. the Delphi method E. time series analysis
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59. Accuracy in forecasting can be measured by: A. MSE B. MRP C. MAPE D. MTM E. A & C
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60. Which of the following would be an advantage of using a sales force composite to develop a demand forecast? A. The sales staff is least affected by changing customer needs. B. The sales force can easily distinguish between customer desires and probable actions. C. The sales staff is often aware of customers' future plans. D. Salespeople are least likely to be influenced by recent events. E. Salespeople are least likely to be biased by sales quotas.
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61. Which phrase most closely describes the Delphi technique? A. associative forecast B. consumer survey C. series of questionnaires D. developed in India E. historical data
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62. The forecasting method which uses anonymous questionnaires to achieve a consensus forecast is: A. sales force opinions B. consumer surveys C. the Delphi method D. time series analysis E. executive opinions
Difficulty: Easy TLO: 3 Taxonomy: Knowledge
63. One reason for using the Delphi method in forecasting is to: A. avoid premature consensus (bandwagon effect) B. achieve a high degree of accuracy C. maintain accountability and responsibility D. be able to replicate results E. prevent hurt feelings
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64. Detecting non-randomness in errors can be done using: A. MSEs B. MAPs C. Control Charts D. Correlation Coefficients E. Strategies
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65. Gradual, long-term movement in time series data is called: A. seasonal variation B. cycles C. irregular variation D. trend E. random variation
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66. The primary difference between seasonality and cycles is: A. the duration of the repeating patterns B. the magnitude of the variation C. the ability to attribute the pattern to a cause D. the direction of the movement E. there are only 4 seasons but 30 cycles
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67. Averaging techniques are useful for: A. distinguishing between random and non-random variations B. smoothing out fluctuations in time series C. eliminating historical data D. providing accuracy in forecasts E. average people
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68. Putting forecast errors into perspective is best done using A. Exponential smoothing B. MAPE C. Linear decision rules D. MAD E. Hindsight
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69. Using the latest observation in a sequence of data to forecast the next period is: A. a moving average forecast B. a naive forecast C. an exponentially smoothed forecast D. an associative forecast E. regression analysis
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70. For the data given below, what would the naive forecast be for the next period (period #5)?
A. 58 B. 62 C. 59.5 D. 61 E. cannot tell from the data given
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Chapter 03 - Forecasting
71. Moving average forecasting techniques do the following: A. immediately reflect changing patterns in the data B. lead changes in the data C. smooth variations in the data D. operate independently of recent data E. assist when organizations are relocating
Difficulty: Hard TLO: 5 Taxonomy: Knowledge
72. Which is not a characteristic of simple moving averages applied to time series data? A. smoothes random variations in the data B. weights each historical value equally C. lags changes in the data D. requires only last period's forecast and actual data E. smoothes real variations in the data
Difficulty: Medium TLO: 5 Taxonomy: Knowledge
73. In order to increase the responsiveness of a forecast made using the moving average technique, the number of data points in the average should be: A. decreased B. increased C. multiplied by a larger alpha D. multiplied by a smaller alpha E. eliminated if the MAD is greater than the MSE
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74. A forecast based on the previous forecast plus a percentage of the forecast error is: A. a naive forecast B. a simple moving average forecast C. a centered moving average forecast D. an exponentially smoothed forecast E. an associative forecast
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75. Which is not a characteristic of exponential smoothing? A. smoothes random variations in the data B. weights each historical value equally C. has an easily altered weighting scheme D. has minimal data storage requirements E. smoothes real variations in the data
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76. Which of the following smoothing constants would make an exponential smoothing forecast equivalent to a naive forecast? A. 0 B. .01 C. .1 D. .5 E. 1.0
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77. Simple exponential smoothing is being used to forecast demand. The previous forecast of 66 turned out to be four units less than actual demand. The next forecast is 66.6, implying a smoothing constant, alpha, equal to: A. .01 B. .10 C. .15 D. .20 E. .60
AACSB: AS Difficulty: Hard TLO: 5 Taxonomy: Application
78. Given an actual demand of 59, a previous forecast of 64, and an alpha of .3, what would the forecast for the next period be using simple exponential smoothing? A. 36.9 B. 57.5 C. 60.5 D. 62.5 E. 65.5
AACSB: AS Difficulty: Medium TLO: 5 Taxonomy: Application
79. Given an actual demand of 105, a forecasted value of 97, and an alpha of .4, the simple exponential smoothing forecast for the next period would be: A. 80.8 B. 93.8 C. 100.2 D. 101.8 E. 108.2
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80. Which of the following possible values of alpha would cause exponential smoothing to respond the most quickly to forecast errors? A. 0 B. .01 C. .05 D. .10 E. .15
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81. A manager uses the following equation to predict monthly receipts: Yt= 40,000 + 150t. What is the forecast for July if t = 0 in April of this year? A. 40,450 B. 40,600 C. 42,100 D. 42,250 E. 42,400
AACSB: AS Difficulty: Medium TLO: 5 Taxonomy: Application
82. In trend-adjusted exponential smoothing, the trend adjusted forecast (TAF) consists of: A. an exponentially smoothed forecast and a smoothed trend factor B. an exponentially smoothed forecast and an estimated trend value C. the old forecast adjusted by a trend factor D. the old forecast and a smoothed trend factor E. a moving average and a trend factor
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83. In the "additive" model for seasonality, seasonality is expressed as a ______________ adjustment to the average; in the multiplicative model, seasonality is expressed as a __________ adjustment to the average. A. quantity, percentage B. percentage, quantity C. quantity, quantity D. percentage, percentage E. qualitative, quantitative
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84. Which technique is useful in computing seasonal relatives? A. double smoothing B. Delphi C. Mean Squared Error (MSE) D. centered moving average E. exponential smoothing
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85. A persistent tendency for forecasts to be greater than or less than the actual values is called: A. bias B. tracking C. control charting D. positive correlation E. linear regression
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86. Which of the following might be used to indicate the cyclical component of a forecast? A. leading variable B. Mean Squared Error (MSE) C. Delphi technique D. exponential smoothing E. Mean Absolute Deviation (MAD)
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87. The primary method for associative forecasting is: A. sensitivity analysis B. regression analysis C. simple moving averages D. centered moving averages E. exponential smoothing
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88. Which term most closely relates to associative forecasting techniques? A. time series data B. expert opinions C. Delphi technique D. consumer survey E. predictor variables
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89. Which of the following corresponds to the predictor variable in simple linear regression? A. regression coefficient B. dependent variable C. independent variable D. predicted variable demand E. coefficient
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90. The mean absolute deviation (MAD) is used to: A. estimate the trend line B. eliminate forecast errors C. measure forecast accuracy D. seasonally adjust the forecast E. all of the above
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91. Given forecast errors of 4, 8, and 3, what is the mean absolute deviation? A. 4 B. 3 C. 5 D. 6 E. 12
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92. Given forecast errors of 5, 0, 4, and 3, what is the mean absolute deviation? A. 4 B. 3 C. 2.5 D. 2 E. 1
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93. Given forecast errors of 5, 0, 4, and 3, what is the bias? A. 4 B. 4 C. 5 D. 12 E. 6
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94. Which of the following is used for constructing a control chart? A. mean absolute deviation (MAD) B. mean squared error (MSE) C. tracking signal (TS) D. bias E. none of the above
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95. The two most important factors in choosing a forecasting technique are: A. cost and time horizon B. accuracy and time horizon C. cost and accuracy D. quantity and quality E. objective and subjective components
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96. The degree of management involvement in short range forecasts is: A. none B. low C. moderate D. high E. total
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97. Which of the following is not necessarily an element of a good forecast? A. estimate of accuracy B. timeliness C. meaningful units D. low cost E. written
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98. Current information on _________ can have a significant impact on forecast accuracy: A. prices B. promotion C. inventory D. competition E. all of the above
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99. A managerial approach toward forecasting which seeks to actively influence demand is: A. reactive B. proactive C. influential D. protracted E. retroactive
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100. Customer service levels can be improved by better: A. mission statements B. control charting C. short term forecast accuracy D. exponential smoothing E. customer selection
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101. Given the following historical data, what is the simple three-period moving average forecast for period 6?
A. 67 B. 115 C. 69 D. 68 E. 68.67
AACSB: AS Difficulty: Easy TLO: 5 Taxonomy: Application
102. Given the following historical data and weights of .5, .3, and .2, what is the three-period moving average forecast for period 5?
A. 144.20 B. 144.80 C. 144.67 D. 143.00 E. 144.00
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103. Use of simple linear regression analysis assumes that: A. Variations around the line are random. B. Deviations around the line are normally distributed. C. Predictions are to be made only within the range of observed values of the predictor variable. D. all of the above E. none of the above
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104. Given forecast errors of 5, 10, and +15, the MAD is: A. 0 B. 10 C. 30 D. 175 E. none of these
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Essay Questions
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105. Develop a forecast for the next period, given the data below, using a 3-period moving average.
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106. Consider the data below:
Using exponential smoothing with alpha = .2, and assuming the forecast for period 11 was 80, what would the forecast for period 14 be?
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107. A manager is using exponential smoothing to predict merchandise returns at a suburban branch of a department store chain. Given a previous forecast of 140 items, an actual number of returns of 148 items, and a smoothing constant equal to .15, what is the forecast for the next period?
AACSB: AS Difficulty: Medium TLO: 5 Taxonomy: Application
108. A manager is using the equation below to forecast quarterly demand for a product: Yt = 6,000 + 80t where t = 0 at Q2 of last year Quarter relatives are Q1 = .6, Q2 = .9, Q3 = 1.3, and Q4 = 1.2. What forecasts are appropriate for the last quarter of this year and the first quarter of next year?
For Q4 of this year t = 6 For Q1 of next year t = 7
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109. Over the past five years, a firm's sales have averaged 250 units in the first quarter of each year, 100 units in the second quarter, 150 units in the third quarter, and 300 units in the fourth quarter. What are appropriate quarter relatives for this firm's sales? Hint: Only minimal computations are necessary.
Since a trend is not present, quarter relatives are simply a percentage of average, which is 200 units. Thus,
AACSB: AS Difficulty: Medium TLO: 5 Taxonomy: Application
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110. A manager has been using a certain technique to forecast demand for gallons of ice cream for the past six periods. Actual and predicted amounts are shown below. Would a naive forecast have produced better results?
Essentially, the student must recognize that either MSE or MAD should be computed for both forecasts and compared. The demand data are stable. Therefore, the most recent value of the series is a reasonable forecast for the next period of time, justifying the nave approach. Some students may also elect to compute control limits to see if the forecasts are in control.
Summary: Current method: MAD = 3.67; MSE =16.8; 2s Control limits 8.2 (OK) Nave method: MAD = 4.40; MSE = 30.0; 2s Control limits 11.0 (OK) The current method is slightly superior both in terms of MAD and MSE. Either method would be considered in control.
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111. A new car dealer has been using exponential smoothing with an alpha of .2 to forecast weekly new car sales. Given the data below, would a naive forecast have provided greater accuracy? Explain. Assume an initial exponential forecast of 60 units in period 2 (i.e., no forecast for period 1).
Summary: Exponential method: MAD = 1.70; MSE = 6.34 Nave method: MAD = 3.00; MSE = 15.25 The exponential forecast method appears to be superior
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112. A CPA firm has been using the following equation to predict annual demand for tax audits: Yt = 55 + 4t Demand for the past few years is shown below. Is the forecast performing as well as it might? Explain.
The student must recognize that either a tracking signal or a control chart is called for and proceed on that basis. In addition, it is necessary for the student to generate the forecasts using the equation so that errors can be determined.
MSE = 11/6 and s = = 3.41. Even with 2s limits (6.82) all values are within the limits. It seems, then, that only random variation is present, so one might say that the forecast is working. One might also observe that the first three errors are negative and the last three are positive. Although six observations constitute a relatively small sample, it may be that the errors are cycling, and this would be a matter to investigate with additional data.
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113. Given the data below, develop a forecast for period 6 using a four-period weighted moving average and weights of .4, .3, .2 and .1
.4(17) + .3(19) + .2(18) + .1(20) = 18.1
AACSB: AS Difficulty: Medium TLO: 5 Taxonomy: Application
114. Use linear regression to develop a predictive model for demand for burial vaults based on sales of caskets.
A) Develop the regression equation.
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115. Given the following data, develop a linear regression model for y as a function of x.
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116. Given the following data, develop a linear regression model for y as a function of x.
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117. Develop a linear trend equation for the data on bread deliveries shown below. Forecast deliveries for period 11 through 14.
Yt = 518.2 + 52.164t r = +.935
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Multiple Choice Questions
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118. The president of State University wants to forecast student enrollments for this academic year based on the following historical data:
What is the forecast for this year using the naive approach? A. 18,750 B. 19,500 C. 21,000 D. 22,000 E. 22,800
Difficulty: Easy TLO: 5 Taxonomy: Knowledge
Essay Questions
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119. Demand for the last four months was:
A) Predict demand for July using each of these methods: 1) a 3-period moving average 2) exponential smoothing with alpha equal to .20 (use a nave forecast for April for your first forecast) B) If the naive approach had been used to predict demand for April through June, what would MAD have been for those months?
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120. A manager wants to choose one of two forecasting alternatives. Each alternative was tested using historical data. The resulting forecast errors for the two are shown in the table. Analyze the data and recommend a course of action to the manager.
Although Alternative #1 has the smaller MSE, it appears to be cycling and steady; Alternative #2 errors after the first three periods are small or zero. For the last six periods, Alternative #2 was much better, suggesting that approach would be better:
AACSB: AS Difficulty: Hard TLO: 7 Taxonomy: Application
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121. A manager uses this equation to predict demand: Yt = 20 + 4t. Over the past 8 periods, demand has been as follows. Are the results acceptable? Explain.
s = 2.10; 2s control limits are 4.20. Although all values are within control limits, the errors may be exhibiting cyclical patterns, which would suggest nonrandomness.
AACSB: AS Difficulty: Medium TLO: 7 Taxonomy: Application
Multiple Choice Questions The president of State University wants to forecast student enrollments for this academic year based on the following historical data:
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122. What is the forecast for this year using a four-year simple moving average? A. 18,750 B. 19,500 C. 21,000 D. 22,650 E. 22,800
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123. What is the forecast for this year using exponential smoothing with alpha = 0.5, if the forecast for two years ago was 16,000? A. 18,750 B. 19,500 C. 21,000 D. 22,650 E. 22,800
AACSB: AS Difficulty: Medium TLO: 5 Taxonomy: Application
124. What is the forecast for this year using the least squares trend line for these data? A. 18,750 B. 19,500 C. 21,000 D. 22,650 E. 22,800
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125. What is the forecast for this year using trend adjusted (double) smoothing with alpha = . 05 and beta = 0.3, if the forecast for last year was 21,000, the forecast for two years ago was 19,000, and the trend estimate for last year's forecast was 1,500? A. 18,750 B. 19,500 C. 21,000 D. 22,650 E. 22,800
AACSB: AS Difficulty: Hard TLO: 5 Taxonomy: Application
The business analyst for Video Sales, Inc. wants to forecast this year's demand for DVD decoders based on the following historical data:
126. What is the forecast for this year using the naive approach? A. 163 B. 180 C. 300 D. 420 E. 510
AACSB: AS Difficulty: Easy TLO: 5 Taxonomy: Application
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Chapter 03 - Forecasting
127. What is the forecast for this year using a three-year weighted moving average with weights of .5, .3, and .2? A. 163 B. 180 C. 300 D. 420 E. 510
AACSB: AS Difficulty: Medium TLO: 5 Taxonomy: Application
128. What is the forecast for this year using exponential smoothing with alpha = .4, if the forecast for two years ago was 750? A. 163 B. 180 C. 300 D. 420 E. 510
AACSB: AS Difficulty: Medium TLO: 5 Taxonomy: Application
129. What is the forecast for this year using the least squares trend line for these data? A. 163 B. 180 C. 300 D. 420 E. 510
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Chapter 03 - Forecasting
130. What is the forecast for this year using trend adjusted (double) smoothing with alpha = 0.3 and beta = 0.2, if the forecast for last year was 310, the forecast for two years ago was 430, and the trend estimate for last year's forecast was 150? A. 162.4 B. 180.3 C. 301.4 D. 403.2 E. 510.0
AACSB: AS Difficulty: Hard TLO: 5 Taxonomy: Application
Professor Very Busy needs to allocate time next week to include time for office hours. He needs to forecast the number of students who will seek appointments. He has gathered the following data:
131. What is this week's forecast using the naive approach? A. 45 B. 50 C. 52 D. 65 E. 78
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Chapter 03 - Forecasting
132. What is this week's forecast using a three-week simple moving average? A. 49 B. 50 C. 52 D. 65 E. 78
AACSB: AS Difficulty: Medium TLO: 5 Taxonomy: Application
133. What is this week's forecast using exponential smoothing with alpha = .2, if the forecast for two weeks ago was 90? A. 49 B. 50 C. 52 D. 65 E. 77
AACSB: AS Difficulty: Medium TLO: 5 Taxonomy: Application
134. What is this week's forecast using the least squares trend line for these data? A. 49 B. 50 C. 52 D. 65 E. 78
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Chapter 03 - Forecasting
135. What is this week's forecast using trend adjusted (double) smoothing with alpha = 0.5 and beta = 0.1, if the forecast for last week was 65, the forecast for two weeks ago was 75, and the trend estimate for last week's forecast was -5? A. 49.3 B. 50.6 C. 51.3 D. 65.4 E. 78.7
AACSB: AS Difficulty: Hard TLO: 5 Taxonomy: Application
A concert promoter is forecasting this year's attendance for one of his concerts based on the following historical data:
136. What is this year's forecast using the naive approach? A. 22,000 B. 20,000 C. 18,000 D. 15,000 E. 12,000
AACSB: AS Difficulty: Easy TLO: 5 Taxonomy: Application
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Chapter 03 - Forecasting
137. What is this year's forecast using a two-year weighted moving average with weights of .7 and .3? A. 19,400 B. 18,600 C. 19,000 D. 11,400 E. 10,600
AACSB: AS Difficulty: Medium TLO: 5 Taxonomy: Application
138. What is this year's forecast using exponential smoothing with alpha = .2, if last year's smoothed forecast was 15,000? A. 20,000 B. 19,000 C. 17,500 D. 16,000 E. 15,000
AACSB: AS Difficulty: Medium TLO: 5 Taxonomy: Application
139. What is this year's forecast using the least squares trend line for these data? A. 20,000 B. 21,000 C. 22,000 D. 23,000 E. 24,000
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Chapter 03 - Forecasting
140. The previous trend line had predicted 18,500 for two years ago, and 19,700 for last year. What was the mean absolute deviation (MAD) for these forecasts? A. 100 B. 200 C. 400 D. 500 E. 800
AACSB: AS Difficulty: Medium TLO: 6 Taxonomy: Application
The dean of a school of business is forecasting total student enrollment for this year's summer session classes based on the following historical data:
141. What is this year's forecast using the naive approach? A. 2,000 B. 2,200 C. 2,800 D. 3,000 E. none of the above
AACSB: AS Difficulty: Easy TLO: 5 Taxonomy: Application
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Chapter 03 - Forecasting
142. What is this year's forecast using a three-year simple moving average? A. 2,667 B. 2,600 C. 2,500 D. 2,400 E. 2,333
AACSB: AS Difficulty: Medium TLO: 5 Taxonomy: Application
143. What is this year's forecast using exponential smoothing with alpha = .4, if last year's smoothed forecast was 2600? A. 2,600 B. 2,760 C. 2,800 D. 3,840 E. 3,000
AACSB: AS Difficulty: Medium TLO: 5 Taxonomy: Application
144. What is the annual rate of change (slope) of the least squares trend line for these data? A. 0 B. 200 C. 400 D. 180 E. 360
AACSB: AS Difficulty: Hard TLO: 5 Taxonomy: Application
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Chapter 03 - Forecasting
145. What is this year's forecast using the least squares trend line for these data? A. 3,600 B. 3,500 C. 3,400 D. 3,300 E. 3,200
AACSB: AS Difficulty: Hard TLO: 5 Taxonomy: Application
The owner of Darkest Tans Unlimited in a local mall is forecasting this month's (October's) demand for the one new tanning booth based on the following historical data:
146. What is this month's forecast using the naive approach? A. 100 B. 160 C. 130 D. 140 E. 120
AACSB: AS Difficulty: Easy TLO: 5 Taxonomy: Application
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Chapter 03 - Forecasting
147. What is this month's forecast using a four-month weighted moving average with weights of .4, .3, .2, and .1? A. 120 B. 129 C. 141 D. 135 E. 140
AACSB: AS Difficulty: Medium TLO: 5 Taxonomy: Application
148. What is this month's forecast using exponential smoothing with alpha = .2, if August's forecast was 145? A. 144 B. 140 C. 142 D. 148 E. 163
AACSB: AS Difficulty: Medium TLO: 5 Taxonomy: Application
149. What is the monthly rate of change (slope) of the least squares trend line for these data? A. 320 B. 102 C. 8 D. -0.4 E. -8
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Chapter 03 - Forecasting
150. What is this month's forecast using the least squares trend line for these data? A. 1,250 B. 128.6 C. 102 D. 158 E. 164
AACSB: AS Difficulty: Hard TLO: 5 Taxonomy: Application
Essay Questions
151. What is this year's forecast using the naive approach?
49
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Chapter 03 - Forecasting
152. What is this year's forecast using a four-year simple moving average?
(45.5)
AACSB: AS Difficulty: Medium TLO: 5 Taxonomy: Application
153. What is this year's forecast using exponential smoothing with alpha = .25, if last year's smoothed forecast was 45?
(45.8)
AACSB: AS Difficulty: Medium TLO: 5 Taxonomy: Application
154. What are this and next year's forecasts using the least squares trend line for these data?
(62; 69)
AACSB: AS Difficulty: Hard TLO: 5 Taxonomy: Application
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Chapter 03 - Forecasting
155. What is this year's forecast using trend adjusted (double) smoothing with alpha = 0.2 and beta = 0.1, if the forecast for last year was 56, the forecast for two years ago was 46, and the trend estimate for last year's forecast was 7?
(61.76)
AACSB: AS Difficulty: Hard TLO: 5 Taxonomy: Application
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Chapter 03 - Forecasting
156. What is the centered moving average for each season?
(Spring 26) (Summer 18) (Fall 34) (Winter 50)
AACSB: AS Difficulty: Medium TLO: 5 Taxonomy: Application
157. What is the seasonal relative for each season?
(Spring 0.895) (Summer 0.615) (Fall 1.020) (Winter 1.471)
AACSB: AS Difficulty: Medium TLO: 5 Taxonomy: Application
158. What is the linear regression trend line for these data (t = 1 for spring, three years ago)?
(y=14.363 + 2.713t)
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Chapter 03 - Forecasting
159. What is this year's seasonally adjusted forecast for each season?
(Spring 44.421) (Summer 32.192) (Fall 56.159) (Winter 84.981)
AACSB: AS Difficulty: Medium TLO: 5 Taxonomy: Application
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