The double exponential smoothing procedure draws a graph containing the observations, smoothed values, and forecasts, versus time. The graph allows you to visually inspect how the weighted averages fit your data.

The double exponential smoothing procedure also displays, along with the graph, the smoothing constants and three measures to help you determine the accuracy of the fitted values: MAPE, MAD, and MSD.

·    The smoothing constants (alpha and gamma) are the weights used in computing the components of the fitted value.

·    The three measures of accuracy are not very informative by themselves, but they are used to compare the fits obtained by using different methods. For all three measures, smaller values generally indicate a better fitting model.

For the sales data, the graph shows that the data are fit fairly well by the double exponential smoothing procedure.