Recurrent Neural Networks with more flexible memory: better predictions than rough volatility
This incremental improvement addresses volatility prediction for financial modeling, offering more stable and efficient training.
The authors tackled the problem of predicting asset price volatility with long memory by extending LSTMs to include flexible timescales, resulting in a 20% performance improvement over rough volatility predictions and halving the training epochs needed.
We extend recurrent neural networks to include several flexible timescales for each dimension of their output, which mechanically improves their abilities to account for processes with long memory or with highly disparate time scales. We compare the ability of vanilla and extended long short term memory networks (LSTMs) to predict asset price volatility, known to have a long memory. Generally, the number of epochs needed to train extended LSTMs is divided by two, while the variation of validation and test losses among models with the same hyperparameters is much smaller. We also show that the model with the smallest validation loss systemically outperforms rough volatility predictions by about 20% when trained and tested on a dataset with multiple time series.