Prediction Error and Forecasting Interval Analysis of Decision Trees with an Application in Renewable Energy Supply Forecasting

Figure 9

The dynamic interval forecasting result. The black lines are the raw daily ratio time series; the red lines are the predicted values; the blue line is the upper forecasted interval; and the yellow line is the lower forecasted interval. The purple line describes whether the data are coved by the interval or not. The circle means the model is retrained on that time point. The upper and lower forecasted interval give an interval that in most cases the real future value will be in, which is similar to the confidence interval that the fitted value is most likely to be covered in.