The extended Ville's inequality for nonintegrable nonnegative supermartingales
- URL: http://arxiv.org/abs/2304.01163v3
- Date: Tue, 08 Oct 2024 17:12:13 GMT
- Title: The extended Ville's inequality for nonintegrable nonnegative supermartingales
- Authors: Hongjian Wang, Aaditya Ramdas,
- Abstract summary: We rigorously present an extended theory of nonnegative supermartingales requiring neither integrability nor finiteness.
We derive a key maximal inequality foreshadowed by Robbins, which we call the extended Ville's inequality.
We derive an extension of the method of mixtures, which applies to $sigma$-finite mixtures of our extended nonnegative supermartingales.
- Score: 30.14855064043107
- License:
- Abstract: Following the initial work by Robbins, we rigorously present an extended theory of nonnegative supermartingales, requiring neither integrability nor finiteness. In particular, we derive a key maximal inequality foreshadowed by Robbins, which we call the extended Ville's inequality, that strengthens the classical Ville's inequality (for integrable nonnegative supermartingales), and also applies to our nonintegrable setting. We derive an extension of the method of mixtures, which applies to $\sigma$-finite mixtures of our extended nonnegative supermartingales. We present some implications of our theory for sequential statistics, such as the use of improper mixtures (priors) in deriving nonparametric confidence sequences and (extended) e-processes.
Related papers
- Nonlinear Stochastic Gradient Descent and Heavy-tailed Noise: A Unified Framework and High-probability Guarantees [56.80920351680438]
We study high-probability convergence in online learning, in the presence of heavy-tailed noise.
Compared to state-of-the-art, who only consider clipping and require noise with bounded $p$-th moments, we provide guarantees for a broad class of nonlinearities.
arXiv Detail & Related papers (2024-10-17T18:25:28Z) - Tighter Constraints of Multi-Qubit Entanglement in Terms of Nonconvex
Entanglement Measures LCREN and LCRENoA [1.2070981561059435]
The monogamy property of characterizing multipart quantum entanglement is an intriguing feature.
Measures satisfying the monogamy inequality are turned out to violate our constraints.
arXiv Detail & Related papers (2024-02-01T09:55:14Z) - Positive Semidefinite Supermartingales and Randomized Matrix
Concentration Inequalities [35.61651875507142]
We present new concentration inequalities for either martingale dependent or exchangeable random symmetric matrices under a variety of tail conditions.
These inequalities are often randomized in a way that renders them strictly tighter than existing deterministic results in the literature.
arXiv Detail & Related papers (2024-01-28T04:22:43Z) - Taming under isoperimetry [0.0]
In this article we propose a Langevin-based scheme calledmathbfsTULA$ to sample from distributions with growing log.
We derive non-asymientKL and consequently consequently satisfy a Log-Sobolev inequality.
arXiv Detail & Related papers (2023-11-15T14:44:16Z) - Negativity of Wigner distribution function as a measure of
incompatibility [0.0]
Measurement incompatibility and the negativity of quasiprobability distribution functions are well-known non-classical aspects of quantum systems.
We establish a connection between the negativity of the Wigner function, a well-known phase-space quasiprobability distribution, of finite-dimensional Hermitian operators and incompatibility among them.
We generalize our treatment for higher dimensional qudits for specific finite-dimensional Gell-Mann operators to observe that with an increase in the dimension of the operators, the negativity of their Wigner distribution, and hence incompatibility, decreases.
arXiv Detail & Related papers (2023-06-13T17:22:56Z) - Concentration of Contractive Stochastic Approximation: Additive and Multiplicative Noise [9.76321513479048]
We establish maximal concentration bounds for the iterates generated by an approximation (SA) under a contractive operator.
We consider two settings where the iterates are potentially unbounded: SA with bounded multiplicative noise and SA with sub-Gaussian additive noise.
arXiv Detail & Related papers (2023-03-28T05:32:30Z) - Exact Non-Oblivious Performance of Rademacher Random Embeddings [79.28094304325116]
This paper revisits the performance of Rademacher random projections.
It establishes novel statistical guarantees that are numerically sharp and non-oblivious with respect to the input data.
arXiv Detail & Related papers (2023-03-21T11:45:27Z) - High-Probability Bounds for Stochastic Optimization and Variational
Inequalities: the Case of Unbounded Variance [59.211456992422136]
We propose algorithms with high-probability convergence results under less restrictive assumptions.
These results justify the usage of the considered methods for solving problems that do not fit standard functional classes in optimization.
arXiv Detail & Related papers (2023-02-02T10:37:23Z) - On Lower Bounds for Standard and Robust Gaussian Process Bandit
Optimization [55.937424268654645]
We consider algorithm-independent lower bounds for the problem of black-box optimization of functions having a bounded norm.
We provide a novel proof technique for deriving lower bounds on the regret, with benefits including simplicity, versatility, and an improved dependence on the error probability.
arXiv Detail & Related papers (2020-08-20T03:48:14Z) - Metrizing Weak Convergence with Maximum Mean Discrepancies [88.54422104669078]
This paper characterizes the maximum mean discrepancies (MMD) that metrize the weak convergence of probability measures for a wide class of kernels.
We prove that, on a locally compact, non-compact, Hausdorff space, the MMD of a bounded continuous Borel measurable kernel k, metrizes the weak convergence of probability measures if and only if k is continuous.
arXiv Detail & Related papers (2020-06-16T15:49:33Z)
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.