• "Those who have knowledge, don't
predict. Those who predict, don't
have knowledge. "
• --Lao Tzu, 6th Century BC Chinese
Forecasting using exponential
• Part 1. Theory
• Part 2. Using Excel: demonstration.
Forecasting a number of library visitors
• Assignment 1, 2
• To learn how to use moving exponential
smoothing method in forecasting
Main idea of the method
• Main idea of the method: smoothing down
variations in the data. Forecast error for the
previous period is taken into account.
Prerequisite data pattern
Horizontal (irregular variations)
Evaluation of the method
• Advantages: rather simple method; More
recent data are considered as being more
• Shortcomings: Not applicable when trend
exists; No definite rule of choosing its
Switch to Excel
Open the Workbook
Using Data Analysis ToolPak in
• Tools Data Analysis Exponential
• Note: if you dont find Data Analysis, it may
be not installed: Tools Add Ins; Analysis
ToolPak should be checked.
Part 2. Working with Excel
• Forecasting a number of visitors of a small
library. Demonstration of the forecasting
procedure using exponential smoothing method
• Assignment 1. Repeating of the forecasting
procedure with the same data
• Assignment 2. Repeating of the forecasting
procedure with the same data but different
parameter (damping factor).