Forecasting Models
REVISED
M05_REND6289_10_IM_C05.QXD 5/7/08 4:42 PM Page 52
C H A P T E R
Forecasting Models
5
TEACHING SUGGESTIONS
Teaching Suggestion 5.1: Wide Use of Forecasting. Forecasting is one of the most important tools a student can master because every firm needs to conduct forecasts. It’s useful to motivate students with the idea that obscure sounding techniques such as exponential smoothing are actually widely used in business, and a good manager is expected to understand forecasting. Regression is commonly accepted as a tool in economic and legal cases. Teaching Suggestion 5.2: Forecasting as an Art and a Science. Forecasting is as much an art as a science. Students should understand that qualitative analysis (judgmental modeling) plays an important role in predicting the future since not every factor can be quantified. Sometimes the best forecast is done by seat-of-thepants methods. Teaching Suggestion 5.3: Use of Simple Models. Many managers want to know what goes on behind the forecast. They may feel uncomfortable with complex statistical models with too many variables. They also need to feel a part of the process. Teaching Suggestion 5.4: Management Input to the Exponential Smoothing Model. One of the strengths of exponential smoothing is that it allows decision makers to input constants that give weight to recent data. Most managers want to feel a part of the modeling process and appreciate the opportunity to provide input. Teaching Suggestion 5.5: Wide Use of Adaptive Models. With today’s dominant use of computers in forecasting, it is possible for a program to constantly track the accuracy of a model’s forecast. It’s important to understand that a program can automatically select the best alpha and beta weights in exponential smoothing. Even if a firm has 10,000 products, the constants can be selected very quickly and easily without human intervention.
Week 1 2 3 4 5 6 7
Actual Bicycle Sales 8 10 9 11 10 13 —
Three-Week Moving Average
(8 10
M05_REND6289_10_IM_C05.QXD 5/7/08 4:42 PM Page 52
C H A P T E R
Forecasting Models
5
TEACHING SUGGESTIONS
Teaching Suggestion 5.1: Wide Use of Forecasting. Forecasting is one of the most important tools a student can master because every firm needs to conduct forecasts. It’s useful to motivate students with the idea that obscure sounding techniques such as exponential smoothing are actually widely used in business, and a good manager is expected to understand forecasting. Regression is commonly accepted as a tool in economic and legal cases. Teaching Suggestion 5.2: Forecasting as an Art and a Science. Forecasting is as much an art as a science. Students should understand that qualitative analysis (judgmental modeling) plays an important role in predicting the future since not every factor can be quantified. Sometimes the best forecast is done by seat-of-thepants methods. Teaching Suggestion 5.3: Use of Simple Models. Many managers want to know what goes on behind the forecast. They may feel uncomfortable with complex statistical models with too many variables. They also need to feel a part of the process. Teaching Suggestion 5.4: Management Input to the Exponential Smoothing Model. One of the strengths of exponential smoothing is that it allows decision makers to input constants that give weight to recent data. Most managers want to feel a part of the modeling process and appreciate the opportunity to provide input. Teaching Suggestion 5.5: Wide Use of Adaptive Models. With today’s dominant use of computers in forecasting, it is possible for a program to constantly track the accuracy of a model’s forecast. It’s important to understand that a program can automatically select the best alpha and beta weights in exponential smoothing. Even if a firm has 10,000 products, the constants can be selected very quickly and easily without human intervention.
Week 1 2 3 4 5 6 7
Actual Bicycle Sales 8 10 9 11 10 13 —
Three-Week Moving Average
(8 10