GAS-Norm: Score-Driven Adaptive Normalization for Non-Stationary Time Series Forecasting in Deep Learning
- URL: http://arxiv.org/abs/2410.03935v1
- Date: Fri, 4 Oct 2024 21:26:12 GMT
- Title: GAS-Norm: Score-Driven Adaptive Normalization for Non-Stationary Time Series Forecasting in Deep Learning
- Authors: Edoardo Urettini, Daniele Atzeni, Reshawn J. Ramjattan, Antonio Carta,
- Abstract summary: We show how changes in the mean and variance of the input data can disrupt the predictive capability of a deep neural network (DNN)
We introduce GAS-Norm, a novel methodology for adaptive time series normalization and forecasting based on the combination of a Generalized Autoregressive Score (GAS) model and a Deep Neural Network.
Results show that deep forecasting models improve their performance in 21 out of 25 settings when combined with GAS-Norm compared to other normalization methods.
- Score: 1.642449952957482
- License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
- Abstract: Despite their popularity, deep neural networks (DNNs) applied to time series forecasting often fail to beat simpler statistical models. One of the main causes of this suboptimal performance is the data non-stationarity present in many processes. In particular, changes in the mean and variance of the input data can disrupt the predictive capability of a DNN. In this paper, we first show how DNN forecasting models fail in simple non-stationary settings. We then introduce GAS-Norm, a novel methodology for adaptive time series normalization and forecasting based on the combination of a Generalized Autoregressive Score (GAS) model and a Deep Neural Network. The GAS approach encompasses a score-driven family of models that estimate the mean and variance at each new observation, providing updated statistics to normalize the input data of the deep model. The output of the DNN is eventually denormalized using the statistics forecasted by the GAS model, resulting in a hybrid approach that leverages the strengths of both statistical modeling and deep learning. The adaptive normalization improves the performance of the model in non-stationary settings. The proposed approach is model-agnostic and can be applied to any DNN forecasting model. To empirically validate our proposal, we first compare GAS-Norm with other state-of-the-art normalization methods. We then combine it with state-of-the-art DNN forecasting models and test them on real-world datasets from the Monash open-access forecasting repository. Results show that deep forecasting models improve their performance in 21 out of 25 settings when combined with GAS-Norm compared to other normalization methods.
Related papers
- On conditional diffusion models for PDE simulations [53.01911265639582]
We study score-based diffusion models for forecasting and assimilation of sparse observations.
We propose an autoregressive sampling approach that significantly improves performance in forecasting.
We also propose a new training strategy for conditional score-based models that achieves stable performance over a range of history lengths.
arXiv Detail & Related papers (2024-10-21T18:31:04Z) - Deep Limit Model-free Prediction in Regression [0.0]
We provide a Model-free approach based on Deep Neural Network (DNN) to accomplish point prediction and prediction interval under a general regression setting.
Our method is more stable and accurate compared to other DNN-based counterparts, especially for optimal point predictions.
arXiv Detail & Related papers (2024-08-18T16:37:53Z) - Conditional Shift-Robust Conformal Prediction for Graph Neural Network [0.0]
Graph Neural Networks (GNNs) have emerged as potent tools for predicting outcomes in graph-structured data.
Despite their efficacy, GNNs have limited ability to provide robust uncertainty estimates.
We propose Conditional Shift Robust (CondSR) conformal prediction for GNNs.
arXiv Detail & Related papers (2024-05-20T11:47:31Z) - SwinVRNN: A Data-Driven Ensemble Forecasting Model via Learned
Distribution Perturbation [16.540748935603723]
We propose a Swin Transformer-based Variational Recurrent Neural Network (SwinVRNN), which is a weather forecasting model combining a SwinRNN predictor with a perturbation module.
SwinVRNN surpasses operational ECMWF Integrated Forecasting System (IFS) on surface variables of 2-m temperature and 6-hourly total precipitation at all lead times up to five days.
arXiv Detail & Related papers (2022-05-26T05:11:58Z) - Probabilistic AutoRegressive Neural Networks for Accurate Long-range
Forecasting [6.295157260756792]
We introduce the Probabilistic AutoRegressive Neural Networks (PARNN)
PARNN is capable of handling complex time series data exhibiting non-stationarity, nonlinearity, non-seasonality, long-range dependence, and chaotic patterns.
We evaluate the performance of PARNN against standard statistical, machine learning, and deep learning models, including Transformers, NBeats, and DeepAR.
arXiv Detail & Related papers (2022-04-01T17:57:36Z) - Post-mortem on a deep learning contest: a Simpson's paradox and the
complementary roles of scale metrics versus shape metrics [61.49826776409194]
We analyze a corpus of models made publicly-available for a contest to predict the generalization accuracy of neural network (NN) models.
We identify what amounts to a Simpson's paradox: where "scale" metrics perform well overall but perform poorly on sub partitions of the data.
We present two novel shape metrics, one data-independent, and the other data-dependent, which can predict trends in the test accuracy of a series of NNs.
arXiv Detail & Related papers (2021-06-01T19:19:49Z) - Rank-R FNN: A Tensor-Based Learning Model for High-Order Data
Classification [69.26747803963907]
Rank-R Feedforward Neural Network (FNN) is a tensor-based nonlinear learning model that imposes Canonical/Polyadic decomposition on its parameters.
First, it handles inputs as multilinear arrays, bypassing the need for vectorization, and can thus fully exploit the structural information along every data dimension.
We establish the universal approximation and learnability properties of Rank-R FNN, and we validate its performance on real-world hyperspectral datasets.
arXiv Detail & Related papers (2021-04-11T16:37:32Z) - Improving predictions of Bayesian neural nets via local linearization [79.21517734364093]
We argue that the Gauss-Newton approximation should be understood as a local linearization of the underlying Bayesian neural network (BNN)
Because we use this linearized model for posterior inference, we should also predict using this modified model instead of the original one.
We refer to this modified predictive as "GLM predictive" and show that it effectively resolves common underfitting problems of the Laplace approximation.
arXiv Detail & Related papers (2020-08-19T12:35:55Z) - Unlabelled Data Improves Bayesian Uncertainty Calibration under
Covariate Shift [100.52588638477862]
We develop an approximate Bayesian inference scheme based on posterior regularisation.
We demonstrate the utility of our method in the context of transferring prognostic models of prostate cancer across globally diverse populations.
arXiv Detail & Related papers (2020-06-26T13:50:19Z) - Bayesian Graph Neural Networks with Adaptive Connection Sampling [62.51689735630133]
We propose a unified framework for adaptive connection sampling in graph neural networks (GNNs)
The proposed framework not only alleviates over-smoothing and over-fitting tendencies of deep GNNs, but also enables learning with uncertainty in graph analytic tasks with GNNs.
arXiv Detail & Related papers (2020-06-07T07:06:35Z) - Spatiotemporal Adaptive Neural Network for Long-term Forecasting of
Financial Time Series [0.2793095554369281]
We investigate whether deep neural networks (DNNs) can be used to forecast time series (TS) forecasts conjointly.
We make use of the dynamic factor graph (DFG) to build a multivariate autoregressive model.
With ACTM, it is possible to vary the autoregressive order of a TS model over time and model a larger set of probability distributions.
arXiv Detail & Related papers (2020-03-27T00:53:11Z)
This list is automatically generated from the titles and abstracts of the papers in this site.
This site does not guarantee the quality of this site (including all information) and is not responsible for any consequences.