Sparsity Regularized and Robust Mean Variance Portfolio Selection Under Ellipsoidal Uncertainty
- URL: http://arxiv.org/abs/2609.11749v1
- Date: Thu, 10 Sep 2026 16:03:35 GMT
- Title: Sparsity Regularized and Robust Mean Variance Portfolio Selection Under Ellipsoidal Uncertainty
- Abstract summary: Uncertainty in the mean return vector is incorporated through an ellipsoidal uncertainty set.<n>We characterize the structure of both local and global minimizers and exploit these properties in the risk minimization and return formulations.<n>Building on this structural insight, we develop a branch-and-bound algorithm tailored to the resulting robust sparse portfolio problems.
- Score: 0.0
- License: http://creativecommons.org/licenses/by/4.0/
- Abstract: We investigate mean-variance portfolio selection with an $\ell_0$-penalty to promote sparsity in asset allocations. Uncertainty in the mean return vector is incorporated through an ellipsoidal uncertainty set, yielding a robust sparse optimization framework. We characterize the structure of both local and global minimizers and exploit these properties in the risk minimization and return maximization formulations. Building on this structural insight, we develop a branch-and-bound algorithm tailored to the resulting robust sparse portfolio problems, together with a new pruning rule that can discard exponentially many candidate portfolios in a single step. Extensive computational experiments on real market data, together with comparisons against a mixed-integer second-order cone programming solver, demonstrate the effectiveness and competitiveness of the proposed approach.
Related papers
- Variable Selection for Feature-Based Newsvendor [1.9851118379257533]
Feature-based newsvendor models balance holding and shortage costs under demand uncertainty.<n>High-dimensional feature sets often hinder interpretability and inflate data collection and implementation costs.<n>This paper studies variable selection for the feature-based newsvendor problem under a hard cardinality constraint on the number of selected features.
arXiv Detail & Related papers (2026-09-01T17:10:24Z) - Deep Reinforcement Learning for Reliability Based Bi-Objective Portfolio Optimization [5.11777500105171]
We propose a deep reinforcement learning framework for reliability based portfolio optimization (MORP-DRL)<n>We jointly optimize expected return and downside risk using three complementary risk measures: variance, Conditional Value-at-Risk (CVaR), and Entropic Value-at-Risk (EVaR)<n>Experiments on ten global equity indices demonstrate that MORP-DRL achieves competitive risk-return performance, reduced downside risk during periods of market stress, and scalability to high-dimensional portfolio settings.
arXiv Detail & Related papers (2026-07-07T06:24:32Z) - A Novel approach to portfolio construction [0.0]
This paper proposes a machine learning-based framework for asset selection and portfolio construction.<n>It is called the Best-Path Algorithm Sparse Graphical Model (BPASGM)<n>Monte Carlo simulations show BPASGM-based portfolios achieve more stable risk-return profiles, lower realized volatility, and superior risk-adjusted performance.
arXiv Detail & Related papers (2026-02-03T09:52:06Z) - Covariance-Aware Simplex Projection for Cardinality-Constrained Portfolio Optimization [0.0]
Covariance-Aware Simplex Projection (CASP) is a two-stage repair operator that selects a target number of assets using volatility-normalized scores.<n>On S&P 500 data (2020-2024), CASP-Basic delivers materially lower portfolio variance than standard Euclidean repair.
arXiv Detail & Related papers (2025-12-23T02:22:53Z) - Modest-Align: Data-Efficient Alignment for Vision-Language Models [67.48633659305592]
Cross-modal alignment models often suffer from overconfidence and degraded performance when operating in resource-constrained settings.<n>We propose Modest-Align, a lightweight alignment framework designed for robustness and efficiency.<n>Our method offers a practical and scalable solution for cross-modal alignment in real-world, low-resource scenarios.
arXiv Detail & Related papers (2025-10-24T16:11:10Z) - Distributionally Robust Optimization with Adversarial Data Contamination [49.89480853499918]
We focus on optimizing Wasserstein-1 DRO objectives for generalized linear models with convex Lipschitz loss functions.<n>Our primary contribution lies in a novel modeling framework that integrates robustness against training data contamination with robustness against distributional shifts.<n>This work establishes the first rigorous guarantees, supported by efficient computation, for learning under the dual challenges of data contamination and distributional shifts.
arXiv Detail & Related papers (2025-07-14T18:34:10Z) - Asymptotically Optimal Linear Best Feasible Arm Identification with Fixed Budget [55.938644481736446]
We introduce a novel algorithm for best feasible arm identification that guarantees an exponential decay in the error probability.<n>We validate our algorithm through comprehensive empirical evaluations across various problem instances with different levels of complexity.
arXiv Detail & Related papers (2025-06-03T02:56:26Z) - Generalization Bounds of Surrogate Policies for Combinatorial Optimization Problems [53.03951222945921]
We analyze smoothed (perturbed) policies, adding controlled random perturbations to the direction used by the linear oracle.<n>Our main contribution is a generalization bound that decomposes the excess risk into perturbation bias, statistical estimation error, and optimization error.<n>We illustrate the scope of the results on applications such as vehicle scheduling, highlighting how smoothing enables both tractable training and controlled generalization.
arXiv Detail & Related papers (2024-07-24T12:00:30Z) - Model-Based Epistemic Variance of Values for Risk-Aware Policy Optimization [59.758009422067]
We consider the problem of quantifying uncertainty over expected cumulative rewards in model-based reinforcement learning.
We propose a new uncertainty Bellman equation (UBE) whose solution converges to the true posterior variance over values.
We introduce a general-purpose policy optimization algorithm, Q-Uncertainty Soft Actor-Critic (QU-SAC) that can be applied for either risk-seeking or risk-averse policy optimization.
arXiv Detail & Related papers (2023-12-07T15:55:58Z) - Robustifying Conditional Portfolio Decisions via Optimal Transport [19.30689697702845]
We propose a data-driven portfolio selection model that integrates side information, conditional estimation and robustness.
We show that the distributionally robust portfolio allocation with side information problem can be reformulated as a finite-dimensional optimization problem.
arXiv Detail & Related papers (2021-03-30T15:56:03Z) - Distributional Robustness and Regularization in Reinforcement Learning [62.23012916708608]
We introduce a new regularizer for empirical value functions and show that it lower bounds the Wasserstein distributionally robust value function.
It suggests using regularization as a practical tool for dealing with $textitexternal uncertainty$ in reinforcement learning.
arXiv Detail & Related papers (2020-03-05T19:56:23Z)
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.