Example of Single Exponential Smoothing

A toothpaste retailer collects sales data and the number of commercials that were broadcast during the previous 60 weeks. The retailer creates a time-series model for prediction of sales.

  1. Open the sample data, ToothpasteSales.MTW.
  2. Choose Stat > Time Series > Single Exp Smoothing.
  3. In Variable, enter Sales.
  4. Select Generate forecasts. In Number of forecasts, enter 6.
  5. Click OK.

Interpret the results

On the smoothing plot, the forecasts and line closely follow the data, especially at the end of the series. The retailer can be 95% confident that the sales will be between approximately 52 and 65 for the next 6 months.

Method

DataSales
Length101

Smoothing Constant

α0.951534

Accuracy Measures

MAPE7.9574
MAD2.5674
MSD11.3479

Forecasts

PeriodForecastLowerUpper
10258.188951.898964.4790
10358.188951.898964.4790
10458.188951.898964.4790
10558.188951.898964.4790
10658.188951.898964.4790
10758.188951.898964.4790