Pub Date : 2026-01-15DOI: 10.1016/j.spl.2026.110655
Pritam Sarkar , Soumi Thakur Chakraborty , Ayan Pal
We investigate the conditions of infinite divisibility of the Exponentiated Pareto (EP) distribution supported on the entire positive half-line , along with its discrete analogue defined on the set of non-negative integers. The EP distribution is defined via the cumulative distribution function (CDF) , where and , is the CDF of Pareto Type II (Lomax) distribution with tail parameter The discrete counterpart is defined as the integer part of a random variable following the EP distribution. The main results assert that both the continuous and discrete versions of the EP distribution are infinitely divisible if A brief discussion of the Lévy process corresponding to the infinitely divisible case for is provided along with a real world data illustration.
研究了整条正半线上(0,∞)支持的幂Pareto (EP)分布的无限可除性条件,以及它在非负整数集上定义的离散模拟。EP分布通过累积分布函数(CDF) [F(x)]α来定义,其中α>;0, F(x)=1−(1+x)−λ,x>;0为尾部参数为λ>;0的Pareto Type II (Lomax)分布的CDF。离散对应项定义为随机变量X遵循EP分布的整数部分。主要结果表明,如果α∈(0,1),EP分布的连续和离散版本都是无限可分的。简要讨论了与α∈(0,1)无限可除情况相对应的lsamvy过程,并给出了一个真实世界的数据说明。
{"title":"When is an Exponentiated Pareto distribution infinitely divisible?","authors":"Pritam Sarkar , Soumi Thakur Chakraborty , Ayan Pal","doi":"10.1016/j.spl.2026.110655","DOIUrl":"10.1016/j.spl.2026.110655","url":null,"abstract":"<div><div>We investigate the conditions of infinite divisibility of the Exponentiated Pareto (EP) distribution supported on the entire positive half-line <span><math><mrow><mo>(</mo><mn>0</mn><mo>,</mo><mi>∞</mi><mo>)</mo></mrow></math></span>, along with its discrete analogue defined on the set of non-negative integers. The EP distribution is defined via the cumulative distribution function (CDF) <span><math><msup><mrow><mrow><mo>[</mo><mi>F</mi><mrow><mo>(</mo><mi>x</mi><mo>)</mo></mrow><mo>]</mo></mrow></mrow><mrow><mi>α</mi></mrow></msup></math></span> , where <span><math><mrow><mi>α</mi><mo>></mo><mn>0</mn></mrow></math></span> and <span><math><mrow><mi>F</mi><mrow><mo>(</mo><mi>x</mi><mo>)</mo></mrow><mo>=</mo><mn>1</mn><mo>−</mo><msup><mrow><mrow><mo>(</mo><mn>1</mn><mo>+</mo><mi>x</mi><mo>)</mo></mrow></mrow><mrow><mo>−</mo><mi>λ</mi></mrow></msup><mo>,</mo><mi>x</mi><mo>></mo><mn>0</mn></mrow></math></span>, is the CDF of Pareto Type II (Lomax) distribution with tail parameter <span><math><mrow><mi>λ</mi><mo>></mo><mn>0</mn><mo>.</mo></mrow></math></span> The discrete counterpart is defined as the integer part of a random variable <span><math><mi>X</mi></math></span> following the EP distribution. The main results assert that both the continuous and discrete versions of the EP distribution are infinitely divisible if <span><math><mrow><mi>α</mi><mo>∈</mo><mrow><mo>(</mo><mn>0</mn><mo>,</mo><mn>1</mn><mo>]</mo></mrow><mo>.</mo></mrow></math></span> A brief discussion of the Lévy process corresponding to the infinitely divisible case for <span><math><mrow><mi>α</mi><mo>∈</mo><mrow><mo>(</mo><mn>0</mn><mo>,</mo><mn>1</mn><mo>]</mo></mrow></mrow></math></span> is provided along with a real world data illustration.</div></div>","PeriodicalId":49475,"journal":{"name":"Statistics & Probability Letters","volume":"232 ","pages":"Article 110655"},"PeriodicalIF":0.7,"publicationDate":"2026-01-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145979445","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-01-15DOI: 10.1016/j.spl.2026.110657
Meiling Zhao
This paper examines the synchronization of a stochastic coupled system driven by fractional Brownian motion with Hurst parameter . A key aspect of our analysis is the study of the uniform boundedness of the fractional Ornstein–Uhlenbeck process with a singular parameter, which serves as a crucial tool in determining the convergence rate of synchronization.
{"title":"Synchronization of coupled system driven by additive fractional Brownian motion","authors":"Meiling Zhao","doi":"10.1016/j.spl.2026.110657","DOIUrl":"10.1016/j.spl.2026.110657","url":null,"abstract":"<div><div>This paper examines the synchronization of a stochastic coupled system driven by fractional Brownian motion with Hurst parameter <span><math><mrow><mn>0</mn><mo><</mo><mi>H</mi><mo><</mo><mfrac><mrow><mn>1</mn></mrow><mrow><mn>2</mn></mrow></mfrac></mrow></math></span>. A key aspect of our analysis is the study of the uniform boundedness of the fractional Ornstein–Uhlenbeck process with a singular parameter, which serves as a crucial tool in determining the convergence rate of synchronization.</div></div>","PeriodicalId":49475,"journal":{"name":"Statistics & Probability Letters","volume":"232 ","pages":"Article 110657"},"PeriodicalIF":0.7,"publicationDate":"2026-01-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146023409","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-01-15DOI: 10.1016/j.spl.2026.110656
Ling-Di Wang , Yu Chen , Yong-Hua Mao , Yu-Hui Zhang
Autoregressive model is a basic one among those time series models, whose stochastic stability is crucial, and often a prerequisite, for statistical inference and other applications. As a specific type of time series model, the linear autoregressive model has garnered significant attention due to its simplicity and ease of generalization. In this paper, we present a comprehensive characterization of stability for the linear autoregressive model with Gaussian innovations, including recurrence and transience, the convergence rate in the ergodicity case, and R-stability in the transience case. The linear autoregressive models are fully classified according to their stability, which is entirely determined by their coefficients.
{"title":"Stochastic stability for linear autoregressive model with Gaussian innovations","authors":"Ling-Di Wang , Yu Chen , Yong-Hua Mao , Yu-Hui Zhang","doi":"10.1016/j.spl.2026.110656","DOIUrl":"10.1016/j.spl.2026.110656","url":null,"abstract":"<div><div>Autoregressive model is a basic one among those time series models, whose stochastic stability is crucial, and often a prerequisite, for statistical inference and other applications. As a specific type of time series model, the linear autoregressive model has garnered significant attention due to its simplicity and ease of generalization. In this paper, we present a comprehensive characterization of stability for the linear autoregressive model with Gaussian innovations, including recurrence and transience, the convergence rate in the ergodicity case, and R-stability in the transience case. The linear autoregressive models are fully classified according to their stability, which is entirely determined by their coefficients.</div></div>","PeriodicalId":49475,"journal":{"name":"Statistics & Probability Letters","volume":"232 ","pages":"Article 110656"},"PeriodicalIF":0.7,"publicationDate":"2026-01-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146023408","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-01-14DOI: 10.1016/j.spl.2026.110651
Charles-Philippe Diez , Luís da Maia , Ivan Nourdin
On August 20, 2025, GPT-5,was reported to have solved an open problem in convex optimization. Motivated by this episode, we conducted a controlled experiment in the Malliavin–Stein framework for central limit theorems. Our objective was to assess whether GPT-5 could go beyond known results by extending a qualitative fourth-moment theorem to a quantitative formulation with explicit convergence rates, both in the Gaussian and in the Poisson settings. To the best of our knowledge, the derivation of such quantitative rates had remained an open problem, in the sense that it had never been addressed in the existing literature. The present paper documents this experiment, presents the results obtained, and discusses their broader implications.
{"title":"Mathematical research with GPT-5: A Malliavin–Stein experiment","authors":"Charles-Philippe Diez , Luís da Maia , Ivan Nourdin","doi":"10.1016/j.spl.2026.110651","DOIUrl":"10.1016/j.spl.2026.110651","url":null,"abstract":"<div><div>On August 20, 2025, GPT-5,was reported to have solved an open problem in convex optimization. Motivated by this episode, we conducted a controlled experiment in the Malliavin–Stein framework for central limit theorems. Our objective was to assess whether GPT-5 could go beyond known results by extending a <em>qualitative</em> fourth-moment theorem to a <em>quantitative</em> formulation with explicit convergence rates, both in the Gaussian and in the Poisson settings. To the best of our knowledge, the derivation of such quantitative rates had remained an open problem, in the sense that it had never been addressed in the existing literature. The present paper documents this experiment, presents the results obtained, and discusses their broader implications.</div></div>","PeriodicalId":49475,"journal":{"name":"Statistics & Probability Letters","volume":"232 ","pages":"Article 110651"},"PeriodicalIF":0.7,"publicationDate":"2026-01-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145979446","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-01-14DOI: 10.1016/j.spl.2026.110653
Matthew Aldridge
If you take a superposition of IID copies of a point process and thin that by a factor of , then the resulting process tends to a Poisson process as . We give a simple proof of this result that highlights its similarity to the law of large numbers and to the law of thin numbers of Harremoës et al.
{"title":"The law of thin processes: A law of large numbers for point processes","authors":"Matthew Aldridge","doi":"10.1016/j.spl.2026.110653","DOIUrl":"10.1016/j.spl.2026.110653","url":null,"abstract":"<div><div>If you take a superposition of <span><math><mi>n</mi></math></span> IID copies of a point process and thin that by a factor of <span><math><mrow><mn>1</mn><mo>/</mo><mi>n</mi></mrow></math></span>, then the resulting process tends to a Poisson process as <span><math><mrow><mi>n</mi><mo>→</mo><mi>∞</mi></mrow></math></span>. We give a simple proof of this result that highlights its similarity to the law of large numbers and to the law of thin numbers of Harremoës et al.</div></div>","PeriodicalId":49475,"journal":{"name":"Statistics & Probability Letters","volume":"232 ","pages":"Article 110653"},"PeriodicalIF":0.7,"publicationDate":"2026-01-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145979447","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Moment inequalities for a class of symmetric distributions","authors":"Weiwei Zhuang, Taizhong Hu","doi":"10.1016/j.spl.2026.110652","DOIUrl":"10.1016/j.spl.2026.110652","url":null,"abstract":"<div><div>For a class of symmetrically distributed random vectors <span><math><mrow><mo>(</mo><mi>X</mi><mo>,</mo><mi>Y</mi><mo>)</mo></mrow></math></span> with finite mean, it is shown that <span><math><mrow><mi>E</mi><mrow><mo>|</mo><mi>X</mi><mo>+</mo><mi>Y</mi><mo>|</mo></mrow><mo>≥</mo><mi>E</mi><mrow><mo>|</mo><mi>X</mi><mo>−</mo><mi>Y</mi><mo>|</mo></mrow></mrow></math></span> holds, along with its generalizations.</div></div>","PeriodicalId":49475,"journal":{"name":"Statistics & Probability Letters","volume":"232 ","pages":"Article 110652"},"PeriodicalIF":0.7,"publicationDate":"2026-01-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145979442","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-01-13DOI: 10.1016/j.spl.2026.110642
Chie Taguchi , Manabu Kuroki
This paper considers a situation where the cause–effect relationships among random variables are represented by a linear structural equation model and the corresponding directed acyclic graph. When the causal effect is not quantitatively identifiable, we propose two novel qualitative identification conditions for causal effects under bad controls.
{"title":"Qualitative identification conditions for causal effects under bad controls in linear structural equation models","authors":"Chie Taguchi , Manabu Kuroki","doi":"10.1016/j.spl.2026.110642","DOIUrl":"10.1016/j.spl.2026.110642","url":null,"abstract":"<div><div>This paper considers a situation where the cause–effect relationships among random variables are represented by a linear structural equation model and the corresponding directed acyclic graph. When the causal effect is not quantitatively identifiable, we propose two novel qualitative identification conditions for causal effects under bad controls.</div></div>","PeriodicalId":49475,"journal":{"name":"Statistics & Probability Letters","volume":"233 ","pages":"Article 110642"},"PeriodicalIF":0.7,"publicationDate":"2026-01-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146080925","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-01-09DOI: 10.1016/j.spl.2026.110641
Thomas Royen
A probability inequality is proved for n-fold convolutions of a smooth cumulative distribution function on , which is multivariate totally positive of order 2 (MTP2). This inequality is sharper than an inequality of the same form as the Gaussian correlation inequality for distribution functions. An example are some multivariate chi-square distributions, derived from the diagonal of a Wishart matrix.
{"title":"A probability inequality for convolutions of MTP2-distribution functions","authors":"Thomas Royen","doi":"10.1016/j.spl.2026.110641","DOIUrl":"10.1016/j.spl.2026.110641","url":null,"abstract":"<div><div>A probability inequality is proved for n-fold convolutions of a smooth cumulative distribution function on <span><math><msubsup><mi>R</mi><mo>+</mo><mi>n</mi></msubsup></math></span>, which is multivariate totally positive of order 2 (MTP<sub>2</sub>). This inequality is sharper than an inequality of the same form as the Gaussian correlation inequality for distribution functions. An example are some multivariate chi-square distributions, derived from the diagonal of a Wishart matrix.</div></div>","PeriodicalId":49475,"journal":{"name":"Statistics & Probability Letters","volume":"232 ","pages":"Article 110641"},"PeriodicalIF":0.7,"publicationDate":"2026-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145979441","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-01-08DOI: 10.1016/j.spl.2026.110639
Bingjun Wang , Hongjun Gao , Mingxia Yuan
This paper investigates the exponential stabilization of stochastic systems driven by -Lévy processes via discrete-time feedback control. We design a control input in the drift term based on discrete-time state observations and prove that there exists an upper bound for the observation step size such that the controlled system achieves both mean square and quasi-sure exponential stability for any step size . An illustrative example validates the effectiveness of the proposed control strategy.
{"title":"Exponential stabilization via discrete-time feedback control for stochastic systems driven by G-Lévy process","authors":"Bingjun Wang , Hongjun Gao , Mingxia Yuan","doi":"10.1016/j.spl.2026.110639","DOIUrl":"10.1016/j.spl.2026.110639","url":null,"abstract":"<div><div>This paper investigates the exponential stabilization of stochastic systems driven by <span><math><mi>G</mi></math></span>-Lévy processes via discrete-time feedback control. We design a control input in the drift term based on discrete-time state observations and prove that there exists an upper bound <span><math><mrow><mover><mrow><mi>τ</mi></mrow><mrow><mo>̄</mo></mrow></mover><mo>></mo><mn>0</mn></mrow></math></span> for the observation step size such that the controlled system achieves both mean square and quasi-sure exponential stability for any step size <span><math><mrow><mi>τ</mi><mo><</mo><mover><mrow><mi>τ</mi></mrow><mrow><mo>̄</mo></mrow></mover></mrow></math></span>. An illustrative example validates the effectiveness of the proposed control strategy.</div></div>","PeriodicalId":49475,"journal":{"name":"Statistics & Probability Letters","volume":"232 ","pages":"Article 110639"},"PeriodicalIF":0.7,"publicationDate":"2026-01-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145928321","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-01-08DOI: 10.1016/j.spl.2026.110640
Nguyen Thi The
We investigate a class of stochastic differential algebraic equations with properly stated leading terms that are well-matched in a specific sense. We establish an existence and uniqueness theorem for this class and investigate the Lyapunov exponents in the linear case.
{"title":"Lyapunov exponents of linear stochastic differential algebraic equations with properly stated leading terms","authors":"Nguyen Thi The","doi":"10.1016/j.spl.2026.110640","DOIUrl":"10.1016/j.spl.2026.110640","url":null,"abstract":"<div><div>We investigate a class of stochastic differential algebraic equations with properly stated leading terms that are well-matched in a specific sense. We establish an existence and uniqueness theorem for this class and investigate the Lyapunov exponents in the linear case.</div></div>","PeriodicalId":49475,"journal":{"name":"Statistics & Probability Letters","volume":"232 ","pages":"Article 110640"},"PeriodicalIF":0.7,"publicationDate":"2026-01-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145928320","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}