Recursive strategy
The recursive strategy is the oldest, most intuitive, and most popular technique to generate multi-step forecasts. To understand a strategy, there are two major regimes we have to understand:
- How is the training of the models done?
- How are the trained models used to generate forecasts?
Let’s take the help of a diagram to understand the recursive strategy:
Figure 17.2 – Recursive strategy for multi-step forecasting
Let’s discuss these regimes in detail.
Training regime
The recursive strategy involves training a single model to perform a one-step-ahead forecast. We can see in Figure 17.1 that we use the window function, , to draw a window from and train the model to predict . And during training, a loss function (which measures the divergence between the output of the model, , and the actual value, ) is used to optimize the parameters of the model.
Forecasting regime
We have trained a model...