Multivariate Probabilistic Time Series Forecasting with Correlated Errors
- URL: http://arxiv.org/abs/2402.01000v3
- Date: Fri, 31 May 2024 14:49:11 GMT
- Title: Multivariate Probabilistic Time Series Forecasting with Correlated Errors
- Authors: Vincent Zhihao Zheng, Lijun Sun,
- Abstract summary: We present a plug-and-play method that learns the covariance structure of errors over multiple steps for autoregressive models with Gaussian-distributed errors.
The learned covariance matrix can be used to calibrate predictions based on observed residuals.
- Score: 17.212396544233307
- License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
- Abstract: Accurately modeling the correlation structure of errors is essential for reliable uncertainty quantification in probabilistic time series forecasting. Recent deep learning models for multivariate time series have developed efficient parameterizations for time-varying contemporaneous covariance, but they often assume temporal independence of errors for simplicity. However, real-world data frequently exhibit significant error autocorrelation and cross-lag correlation due to factors such as missing covariates. In this paper, we present a plug-and-play method that learns the covariance structure of errors over multiple steps for autoregressive models with Gaussian-distributed errors. To achieve scalable inference and computational efficiency, we model the contemporaneous covariance using a low-rank-plus-diagonal parameterization and characterize cross-covariance through a group of independent latent temporal processes. The learned covariance matrix can be used to calibrate predictions based on observed residuals. We evaluate our method on probabilistic models built on RNN and Transformer architectures, and the results confirm the effectiveness of our approach in enhancing predictive accuracy and uncertainty quantification without significantly increasing the parameter size.
Related papers
- Structured Radial Basis Function Network: Modelling Diversity for
Multiple Hypotheses Prediction [51.82628081279621]
Multi-modal regression is important in forecasting nonstationary processes or with a complex mixture of distributions.
A Structured Radial Basis Function Network is presented as an ensemble of multiple hypotheses predictors for regression problems.
It is proved that this structured model can efficiently interpolate this tessellation and approximate the multiple hypotheses target distribution.
arXiv Detail & Related papers (2023-09-02T01:27:53Z) - Better Batch for Deep Probabilistic Time Series Forecasting [15.31488551912888]
We propose an innovative training method that incorporates error autocorrelation to enhance probabilistic forecasting accuracy.
Our method constructs a mini-batch as a collection of $D$ consecutive time series segments for model training.
It explicitly learns a time-varying covariance matrix over each mini-batch, encoding error correlation among adjacent time steps.
arXiv Detail & Related papers (2023-05-26T15:36:59Z) - Scalable Dynamic Mixture Model with Full Covariance for Probabilistic
Traffic Forecasting [16.04029885574568]
We propose a dynamic mixture of zero-mean Gaussian distributions for the time-varying error process.
The proposed method can be seamlessly integrated into existing deep-learning frameworks with only a few additional parameters to be learned.
We evaluate the proposed method on a traffic speed forecasting task and find that our method not only improves model horizons but also provides interpretabletemporal correlation structures.
arXiv Detail & Related papers (2022-12-10T22:50:00Z) - Learning Asynchronous and Error-prone Longitudinal Data via Functional
Calibration [4.446626375802735]
We propose a new functional calibration approach to efficiently learn longitudinal covariate processes based on functional data with measurement error.
For regression with time-invariant coefficients, our estimator is root-n consistent, and root-n normal; for time-varying coefficient models, our estimator has the optimal varying coefficient model convergence rate.
The feasibility and usability of the proposed methods are verified by simulations and an application to the Study of Women's Health Across the Nation.
arXiv Detail & Related papers (2022-09-28T03:27:31Z) - Benign Overfitting in Time Series Linear Model with
Over-Parameterization [5.68558935178946]
We develop a theory for excess risk of the estimator under multiple dependence types.
We show that the convergence rate of risks with short-memory processes is identical to that of cases with independent data.
arXiv Detail & Related papers (2022-04-18T15:26:58Z) - TACTiS: Transformer-Attentional Copulas for Time Series [76.71406465526454]
estimation of time-varying quantities is a fundamental component of decision making in fields such as healthcare and finance.
We propose a versatile method that estimates joint distributions using an attention-based decoder.
We show that our model produces state-of-the-art predictions on several real-world datasets.
arXiv Detail & Related papers (2022-02-07T21:37:29Z) - Anomaly Detection of Time Series with Smoothness-Inducing Sequential
Variational Auto-Encoder [59.69303945834122]
We present a Smoothness-Inducing Sequential Variational Auto-Encoder (SISVAE) model for robust estimation and anomaly detection of time series.
Our model parameterizes mean and variance for each time-stamp with flexible neural networks.
We show the effectiveness of our model on both synthetic datasets and public real-world benchmarks.
arXiv Detail & Related papers (2021-02-02T06:15:15Z) - Adjusting for Autocorrelated Errors in Neural Networks for Time Series
Regression and Forecasting [10.659189276058948]
We learn the autocorrelation coefficient jointly with the model parameters in order to adjust for autocorrelated errors.
For time series regression, large-scale experiments indicate that our method outperforms the Prais-Winsten method.
Results across a wide range of real-world datasets show that our method enhances performance in almost all cases.
arXiv Detail & Related papers (2021-01-28T04:25:51Z) - Accounting for Unobserved Confounding in Domain Generalization [107.0464488046289]
This paper investigates the problem of learning robust, generalizable prediction models from a combination of datasets.
Part of the challenge of learning robust models lies in the influence of unobserved confounders.
We demonstrate the empirical performance of our approach on healthcare data from different modalities.
arXiv Detail & Related papers (2020-07-21T08:18:06Z) - Good Classifiers are Abundant in the Interpolating Regime [64.72044662855612]
We develop a methodology to compute precisely the full distribution of test errors among interpolating classifiers.
We find that test errors tend to concentrate around a small typical value $varepsilon*$, which deviates substantially from the test error of worst-case interpolating model.
Our results show that the usual style of analysis in statistical learning theory may not be fine-grained enough to capture the good generalization performance observed in practice.
arXiv Detail & Related papers (2020-06-22T21:12:31Z) - Machine learning for causal inference: on the use of cross-fit
estimators [77.34726150561087]
Doubly-robust cross-fit estimators have been proposed to yield better statistical properties.
We conducted a simulation study to assess the performance of several estimators for the average causal effect (ACE)
When used with machine learning, the doubly-robust cross-fit estimators substantially outperformed all of the other estimators in terms of bias, variance, and confidence interval coverage.
arXiv Detail & Related papers (2020-04-21T23:09:55Z)
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.