Robust Gaussian Process Regression with a Bias Model
- URL: http://arxiv.org/abs/2001.04639v1
- Date: Tue, 14 Jan 2020 06:21:51 GMT
- Title: Robust Gaussian Process Regression with a Bias Model
- Authors: Chiwoo Park, David J. Borth, Nicholas S. Wilson, Chad N. Hunter, and
Fritz J. Friedersdorf
- Abstract summary: Most existing approaches replace an outlier-prone Gaussian likelihood with a non-Gaussian likelihood induced from a heavy tail distribution.
The proposed approach models an outlier as a noisy and biased observation of an unknown regression function.
Conditioned on the bias estimates, the robust GP regression can be reduced to a standard GP regression problem.
- Score: 0.6850683267295248
- License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
- Abstract: This paper presents a new approach to a robust Gaussian process (GP)
regression. Most existing approaches replace an outlier-prone Gaussian
likelihood with a non-Gaussian likelihood induced from a heavy tail
distribution, such as the Laplace distribution and Student-t distribution.
However, the use of a non-Gaussian likelihood would incur the need for a
computationally expensive Bayesian approximate computation in the posterior
inferences. The proposed approach models an outlier as a noisy and biased
observation of an unknown regression function, and accordingly, the likelihood
contains bias terms to explain the degree of deviations from the regression
function. We entail how the biases can be estimated accurately with other
hyperparameters by a regularized maximum likelihood estimation. Conditioned on
the bias estimates, the robust GP regression can be reduced to a standard GP
regression problem with analytical forms of the predictive mean and variance
estimates. Therefore, the proposed approach is simple and very computationally
attractive. It also gives a very robust and accurate GP estimate for many
tested scenarios. For the numerical evaluation, we perform a comprehensive
simulation study to evaluate the proposed approach with the comparison to the
existing robust GP approaches under various simulated scenarios of different
outlier proportions and different noise levels. The approach is applied to data
from two measurement systems, where the predictors are based on robust
environmental parameter measurements and the response variables utilize more
complex chemical sensing methods that contain a certain percentage of outliers.
The utility of the measurement systems and value of the environmental data are
improved through the computationally efficient GP regression and bias model.
Related papers
- Multivariate root-n-consistent smoothing parameter free matching estimators and estimators of inverse density weighted expectations [51.000851088730684]
We develop novel modifications of nearest-neighbor and matching estimators which converge at the parametric $sqrt n $-rate.
We stress that our estimators do not involve nonparametric function estimators and in particular do not rely on sample-size dependent parameters smoothing.
arXiv Detail & Related papers (2024-07-11T13:28:34Z) - Model-Based Reparameterization Policy Gradient Methods: Theory and
Practical Algorithms [88.74308282658133]
Reization (RP) Policy Gradient Methods (PGMs) have been widely adopted for continuous control tasks in robotics and computer graphics.
Recent studies have revealed that, when applied to long-term reinforcement learning problems, model-based RP PGMs may experience chaotic and non-smooth optimization landscapes.
We propose a spectral normalization method to mitigate the exploding variance issue caused by long model unrolls.
arXiv Detail & Related papers (2023-10-30T18:43:21Z) - Engression: Extrapolation through the Lens of Distributional Regression [2.519266955671697]
We propose a neural network-based distributional regression methodology called engression'
An engression model is generative in the sense that we can sample from the fitted conditional distribution and is also suitable for high-dimensional outcomes.
We show that engression can successfully perform extrapolation under some assumptions such as monotonicity, whereas traditional regression approaches such as least-squares or quantile regression fall short under the same assumptions.
arXiv Detail & Related papers (2023-07-03T08:19:00Z) - Robust Gaussian Process Regression with Huber Likelihood [2.7184224088243365]
We propose a robust process model in the Gaussian process framework with the likelihood of observed data expressed as the Huber probability distribution.
The proposed model employs weights based on projection statistics to scale residuals and bound the influence of vertical outliers and bad leverage points on the latent functions estimates.
arXiv Detail & Related papers (2023-01-19T02:59:33Z) - Sparse high-dimensional linear regression with a partitioned empirical
Bayes ECM algorithm [62.997667081978825]
We propose a computationally efficient and powerful Bayesian approach for sparse high-dimensional linear regression.
Minimal prior assumptions on the parameters are used through the use of plug-in empirical Bayes estimates.
The proposed approach is implemented in the R package probe.
arXiv Detail & Related papers (2022-09-16T19:15:50Z) - Maximum Likelihood Estimation in Gaussian Process Regression is
Ill-Posed [7.018149356115115]
It remains an open problem to establish the circumstances in which maximum likelihood estimation is well-posed.
This article identifies scenarios where the maximum likelihood estimator fails to be well-posed.
Although the failure of maximum likelihood estimation is part of Gaussian process folklore, these rigorous theoretical results appear to be the first of their kind.
arXiv Detail & Related papers (2022-03-17T09:00:39Z) - Heavy-tailed Streaming Statistical Estimation [58.70341336199497]
We consider the task of heavy-tailed statistical estimation given streaming $p$ samples.
We design a clipped gradient descent and provide an improved analysis under a more nuanced condition on the noise of gradients.
arXiv Detail & Related papers (2021-08-25T21:30:27Z) - Scalable Marginal Likelihood Estimation for Model Selection in Deep
Learning [78.83598532168256]
Marginal-likelihood based model-selection is rarely used in deep learning due to estimation difficulties.
Our work shows that marginal likelihoods can improve generalization and be useful when validation data is unavailable.
arXiv Detail & Related papers (2021-04-11T09:50:24Z) - SLOE: A Faster Method for Statistical Inference in High-Dimensional
Logistic Regression [68.66245730450915]
We develop an improved method for debiasing predictions and estimating frequentist uncertainty for practical datasets.
Our main contribution is SLOE, an estimator of the signal strength with convergence guarantees that reduces the computation time of estimation and inference by orders of magnitude.
arXiv Detail & Related papers (2021-03-23T17:48:56Z) - Robust Gaussian Process Regression Based on Iterative Trimming [6.912744078749024]
This paper presents a new robust GP regression algorithm that iteratively trims the most extreme data points.
It can greatly improve the model accuracy for contaminated data even in the presence of extreme or abundant outliers.
As a practical example in the astrophysical study, we show that this method can precisely determine the main-sequence ridge line in the color-magnitude diagram of star clusters.
arXiv Detail & Related papers (2020-11-22T16:43:35Z) - Maximum likelihood estimation and uncertainty quantification for
Gaussian process approximation of deterministic functions [10.319367855067476]
This article provides one of the first theoretical analyses in the context of Gaussian process regression with a noiseless dataset.
We show that the maximum likelihood estimation of the scale parameter alone provides significant adaptation against misspecification of the Gaussian process model.
arXiv Detail & Related papers (2020-01-29T17:20:21Z)
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.