Model averaging in the space of probability distributions
- URL: http://arxiv.org/abs/2507.11719v1
- Date: Tue, 15 Jul 2025 20:41:57 GMT
- Title: Model averaging in the space of probability distributions
- Authors: Emmanouil Androulakis, Georgios I. Papayiannis, Athanasios N. Yannacopoulos,
- Abstract summary: We study aggregation schemes in the space of probability distributions metrized in terms of the Wasserstein distance.<n>We employ regularization schemes motivated by the standard elastic net penalization, which is shown to consistently yield models enjoying sparsity properties.<n>The proposed approach is applied to a real-world dataset of insurance losses to estimate the claim size distribution and the associated tail risk.
- Score: 0.0
- License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
- Abstract: This work investigates the problem of model averaging in the context of measure-valued data. Specifically, we study aggregation schemes in the space of probability distributions metrized in terms of the Wasserstein distance. The resulting aggregate models, defined via Wasserstein barycenters, are optimally calibrated to empirical data. To enhance model performance, we employ regularization schemes motivated by the standard elastic net penalization, which is shown to consistently yield models enjoying sparsity properties. The consistency properties of the proposed averaging schemes with respect to sample size are rigorously established using the variational framework of $\Gamma$-convergence. The performance of the methods is evaluated through carefully designed synthetic experiments that assess behavior across a range of distributional characteristics and stress conditions. Finally, the proposed approach is applied to a real-world dataset of insurance losses - characterized by heavy-tailed behavior - to estimate the claim size distribution and the associated tail risk.
Related papers
- Covariate-dependent Graphical Model Estimation via Neural Networks with Statistical Guarantees [18.106204331704156]
We consider settings where the graph structure is co-dependent, and investigate a deep neural network-based approach to estimate it.<n> Theoretical results with PAC guarantees are established for the method, under assumptions commonly used in an Empirical Risk Minimization framework.<n>The performance of the proposed method is evaluated on several synthetic data settings and benchmarked against existing approaches.
arXiv Detail & Related papers (2025-04-23T02:13:36Z) - Model-free Methods for Event History Analysis and Efficient Adjustment (PhD Thesis) [55.2480439325792]
This thesis is a series of independent contributions to statistics unified by a model-free perspective.<n>The first chapter elaborates on how a model-free perspective can be used to formulate flexible methods that leverage prediction techniques from machine learning.<n>The second chapter studies the concept of local independence, which describes whether the evolution of one process is directly influenced by another.
arXiv Detail & Related papers (2025-02-11T19:24:09Z) - Theory on Score-Mismatched Diffusion Models and Zero-Shot Conditional Samplers [49.97755400231656]
We present the first performance guarantee with explicit dimensional dependencies for general score-mismatched diffusion samplers.<n>We show that score mismatches result in an distributional bias between the target and sampling distributions, proportional to the accumulated mismatch between the target and training distributions.<n>This result can be directly applied to zero-shot conditional samplers for any conditional model, irrespective of measurement noise.
arXiv Detail & Related papers (2024-10-17T16:42:12Z) - A Likelihood Based Approach to Distribution Regression Using Conditional Deep Generative Models [6.647819824559201]
We study the large-sample properties of a likelihood-based approach for estimating conditional deep generative models.
Our results lead to the convergence rate of a sieve maximum likelihood estimator for estimating the conditional distribution.
arXiv Detail & Related papers (2024-10-02T20:46:21Z) - Generative Assignment Flows for Representing and Learning Joint Distributions of Discrete Data [2.6499018693213316]
We introduce a novel generative model for the representation of joint probability distributions of discrete random variables.<n>The approach uses measure transport by randomized assignment flows on the statistical submanifold of factorizing distributions.
arXiv Detail & Related papers (2024-06-06T21:58:33Z) - Rejection via Learning Density Ratios [50.91522897152437]
Classification with rejection emerges as a learning paradigm which allows models to abstain from making predictions.<n>We propose a different distributional perspective, where we seek to find an idealized data distribution which maximizes a pretrained model's performance.<n>Our framework is tested empirically over clean and noisy datasets.
arXiv Detail & Related papers (2024-05-29T01:32:17Z) - Quantifying Distribution Shifts and Uncertainties for Enhanced Model Robustness in Machine Learning Applications [0.0]
This study explores model adaptation and generalization by utilizing synthetic data.
We employ quantitative measures such as Kullback-Leibler divergence, Jensen-Shannon distance, and Mahalanobis distance to assess data similarity.
Our findings suggest that utilizing statistical measures, such as the Mahalanobis distance, to determine whether model predictions fall within the low-error "interpolation regime" or the high-error "extrapolation regime" provides a complementary method for assessing distribution shift and model uncertainty.
arXiv Detail & Related papers (2024-05-03T10:05:31Z) - Aggregation Weighting of Federated Learning via Generalization Bound
Estimation [65.8630966842025]
Federated Learning (FL) typically aggregates client model parameters using a weighting approach determined by sample proportions.
We replace the aforementioned weighting method with a new strategy that considers the generalization bounds of each local model.
arXiv Detail & Related papers (2023-11-10T08:50:28Z) - Statistically Optimal Generative Modeling with Maximum Deviation from the Empirical Distribution [2.1146241717926664]
We show that the Wasserstein GAN, constrained to left-invertible push-forward maps, generates distributions that avoid replication and significantly deviate from the empirical distribution.
Our most important contribution provides a finite-sample lower bound on the Wasserstein-1 distance between the generative distribution and the empirical one.
We also establish a finite-sample upper bound on the distance between the generative distribution and the true data-generating one.
arXiv Detail & Related papers (2023-07-31T06:11:57Z) - Score Approximation, Estimation and Distribution Recovery of Diffusion
Models on Low-Dimensional Data [68.62134204367668]
This paper studies score approximation, estimation, and distribution recovery of diffusion models, when data are supported on an unknown low-dimensional linear subspace.
We show that with a properly chosen neural network architecture, the score function can be both accurately approximated and efficiently estimated.
The generated distribution based on the estimated score function captures the data geometric structures and converges to a close vicinity of the data distribution.
arXiv Detail & Related papers (2023-02-14T17:02:35Z) - A likelihood approach to nonparametric estimation of a singular
distribution using deep generative models [4.329951775163721]
We investigate a likelihood approach to nonparametric estimation of a singular distribution using deep generative models.
We prove that a novel and effective solution exists by perturbing the data with an instance noise.
We also characterize the class of distributions that can be efficiently estimated via deep generative models.
arXiv Detail & Related papers (2021-05-09T23:13:58Z) - 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)
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.