Pub Date : 2024-06-04DOI: 10.1017/s0269964824000081
James Allen Fill, Ao Sun
<p>Given a sequence of independent random vectors taking values in <span><span><img data-mimesubtype="png" data-type="" src="https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240603131552515-0032:S0269964824000081:S0269964824000081_inline1.png"><span data-mathjax-type="texmath"><span>${mathbb R}^d$</span></span></img></span></span> and having common continuous distribution function <span>F</span>, say that the <span><span><img data-mimesubtype="png" data-type="" src="https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240603131552515-0032:S0269964824000081:S0269964824000081_inline2.png"><span data-mathjax-type="texmath"><span>$n^{rm scriptsize}$</span></span></img></span></span>th observation <span>sets a (Pareto) record</span> if it is not dominated (in every coordinate) by any preceding observation. Let <span><span><img data-mimesubtype="png" data-type="" src="https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240603131552515-0032:S0269964824000081:S0269964824000081_inline3.png"><span data-mathjax-type="texmath"><span>$p_n(F) equiv p_{n, d}(F)$</span></span></img></span></span> denote the probability that the <span><span><img data-mimesubtype="png" data-type="" src="https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240603131552515-0032:S0269964824000081:S0269964824000081_inline4.png"><span data-mathjax-type="texmath"><span>$n^{rm scriptsize}$</span></span></img></span></span>th observation sets a record. There are many interesting questions to address concerning <span>p<span>n</span></span> and multivariate records more generally, but this short paper focuses on how <span>p<span>n</span></span> varies with <span>F</span>, particularly if, under <span>F</span>, the coordinates exhibit negative dependence or positive dependence (rather than independence, a more-studied case). We introduce new notions of negative and positive dependence ideally suited for such a study, called <span>negative record-setting probability dependence</span> (NRPD) and <span>positive record-setting probability dependence</span> (PRPD), relate these notions to existing notions of dependence, and for fixed <span><span><img data-mimesubtype="png" data-type="" src="https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240603131552515-0032:S0269964824000081:S0269964824000081_inline5.png"><span data-mathjax-type="texmath"><span>$d geq 2$</span></span></img></span></span> and <span><span><img data-mimesubtype="png" data-type="" src="https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240603131552515-0032:S0269964824000081:S0269964824000081_inline6.png"><span data-mathjax-type="texmath"><span>$n geq 1$</span></span></img></span></span> prove that the image of the mapping <span>p<span>n</span></span> on the domain of NRPD (respectively, PRPD) distributions is <span><span><img data-mimesubtype="png" data-type="" src="https://stati
{"title":"On the probability of a Pareto record","authors":"James Allen Fill, Ao Sun","doi":"10.1017/s0269964824000081","DOIUrl":"https://doi.org/10.1017/s0269964824000081","url":null,"abstract":"<p>Given a sequence of independent random vectors taking values in <span><span><img data-mimesubtype=\"png\" data-type=\"\" src=\"https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240603131552515-0032:S0269964824000081:S0269964824000081_inline1.png\"><span data-mathjax-type=\"texmath\"><span>${mathbb R}^d$</span></span></img></span></span> and having common continuous distribution function <span>F</span>, say that the <span><span><img data-mimesubtype=\"png\" data-type=\"\" src=\"https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240603131552515-0032:S0269964824000081:S0269964824000081_inline2.png\"><span data-mathjax-type=\"texmath\"><span>$n^{rm scriptsize}$</span></span></img></span></span>th observation <span>sets a (Pareto) record</span> if it is not dominated (in every coordinate) by any preceding observation. Let <span><span><img data-mimesubtype=\"png\" data-type=\"\" src=\"https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240603131552515-0032:S0269964824000081:S0269964824000081_inline3.png\"><span data-mathjax-type=\"texmath\"><span>$p_n(F) equiv p_{n, d}(F)$</span></span></img></span></span> denote the probability that the <span><span><img data-mimesubtype=\"png\" data-type=\"\" src=\"https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240603131552515-0032:S0269964824000081:S0269964824000081_inline4.png\"><span data-mathjax-type=\"texmath\"><span>$n^{rm scriptsize}$</span></span></img></span></span>th observation sets a record. There are many interesting questions to address concerning <span>p<span>n</span></span> and multivariate records more generally, but this short paper focuses on how <span>p<span>n</span></span> varies with <span>F</span>, particularly if, under <span>F</span>, the coordinates exhibit negative dependence or positive dependence (rather than independence, a more-studied case). We introduce new notions of negative and positive dependence ideally suited for such a study, called <span>negative record-setting probability dependence</span> (NRPD) and <span>positive record-setting probability dependence</span> (PRPD), relate these notions to existing notions of dependence, and for fixed <span><span><img data-mimesubtype=\"png\" data-type=\"\" src=\"https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240603131552515-0032:S0269964824000081:S0269964824000081_inline5.png\"><span data-mathjax-type=\"texmath\"><span>$d geq 2$</span></span></img></span></span> and <span><span><img data-mimesubtype=\"png\" data-type=\"\" src=\"https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240603131552515-0032:S0269964824000081:S0269964824000081_inline6.png\"><span data-mathjax-type=\"texmath\"><span>$n geq 1$</span></span></img></span></span> prove that the image of the mapping <span>p<span>n</span></span> on the domain of NRPD (respectively, PRPD) distributions is <span><span><img data-mimesubtype=\"png\" data-type=\"\" src=\"https://stati","PeriodicalId":54582,"journal":{"name":"Probability in the Engineering and Informational Sciences","volume":"35 1","pages":""},"PeriodicalIF":1.1,"publicationDate":"2024-06-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141254853","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-05-07DOI: 10.1017/s026996482400007x
Ramkrishna Jyoti Samanta, Sangita Das, N. Balakrishnan
<p>In this work, we consider two sets of dependent variables <span><span><img data-mimesubtype="png" data-type="" src="https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240507063908403-0649:S026996482400007X:S026996482400007X_inline1.png"><span data-mathjax-type="texmath"><span>${X_{1},ldots,X_{n}}$</span></span></img></span></span> and <span><span><img data-mimesubtype="png" data-type="" src="https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240507063908403-0649:S026996482400007X:S026996482400007X_inline2.png"><span data-mathjax-type="texmath"><span>${Y_{1},ldots,Y_{n}}$</span></span></img></span></span>, where <span><span><img data-mimesubtype="png" data-type="" src="https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240507063908403-0649:S026996482400007X:S026996482400007X_inline3.png"><span data-mathjax-type="texmath"><span>$X_{i}sim EW(alpha_{i},lambda_{i},k_{i})$</span></span></img></span></span> and <span><span><img data-mimesubtype="png" data-type="" src="https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240507063908403-0649:S026996482400007X:S026996482400007X_inline4.png"><span data-mathjax-type="texmath"><span>$Y_{i}sim EW(beta_{i},mu_{i},l_{i})$</span></span></img></span></span>, for <span><span><img data-mimesubtype="png" data-type="" src="https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240507063908403-0649:S026996482400007X:S026996482400007X_inline5.png"><span data-mathjax-type="texmath"><span>$i=1,ldots, n$</span></span></img></span></span>, which are coupled by Archimedean copulas having different generators. We then establish different inequalities between two extremes, namely, <span><span><img data-mimesubtype="png" data-type="" src="https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240507063908403-0649:S026996482400007X:S026996482400007X_inline6.png"><span data-mathjax-type="texmath"><span>$X_{1:n}$</span></span></img></span></span> and <span><span><img data-mimesubtype="png" data-type="" src="https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240507063908403-0649:S026996482400007X:S026996482400007X_inline7.png"><span data-mathjax-type="texmath"><span>$Y_{1:n}$</span></span></img></span></span> and <span><span><img data-mimesubtype="png" data-type="" src="https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240507063908403-0649:S026996482400007X:S026996482400007X_inline8.png"><span data-mathjax-type="texmath"><span>$X_{n:n}$</span></span></img></span></span> and <span><span><img data-mimesubtype="png" data-type="" src="https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240507063908403-0649:S026996482400007X:S026996482400007X_inline9.png"><span data-mathjax-type="texmath"><span>$Y_{n:n}$</span></span></img></span></span>, in terms of the usual stochastic, star, Lorenz, hazard rate, reversed hazar
{"title":"Orderings of extremes among dependent extended Weibull random variables","authors":"Ramkrishna Jyoti Samanta, Sangita Das, N. Balakrishnan","doi":"10.1017/s026996482400007x","DOIUrl":"https://doi.org/10.1017/s026996482400007x","url":null,"abstract":"<p>In this work, we consider two sets of dependent variables <span><span><img data-mimesubtype=\"png\" data-type=\"\" src=\"https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240507063908403-0649:S026996482400007X:S026996482400007X_inline1.png\"><span data-mathjax-type=\"texmath\"><span>${X_{1},ldots,X_{n}}$</span></span></img></span></span> and <span><span><img data-mimesubtype=\"png\" data-type=\"\" src=\"https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240507063908403-0649:S026996482400007X:S026996482400007X_inline2.png\"><span data-mathjax-type=\"texmath\"><span>${Y_{1},ldots,Y_{n}}$</span></span></img></span></span>, where <span><span><img data-mimesubtype=\"png\" data-type=\"\" src=\"https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240507063908403-0649:S026996482400007X:S026996482400007X_inline3.png\"><span data-mathjax-type=\"texmath\"><span>$X_{i}sim EW(alpha_{i},lambda_{i},k_{i})$</span></span></img></span></span> and <span><span><img data-mimesubtype=\"png\" data-type=\"\" src=\"https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240507063908403-0649:S026996482400007X:S026996482400007X_inline4.png\"><span data-mathjax-type=\"texmath\"><span>$Y_{i}sim EW(beta_{i},mu_{i},l_{i})$</span></span></img></span></span>, for <span><span><img data-mimesubtype=\"png\" data-type=\"\" src=\"https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240507063908403-0649:S026996482400007X:S026996482400007X_inline5.png\"><span data-mathjax-type=\"texmath\"><span>$i=1,ldots, n$</span></span></img></span></span>, which are coupled by Archimedean copulas having different generators. We then establish different inequalities between two extremes, namely, <span><span><img data-mimesubtype=\"png\" data-type=\"\" src=\"https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240507063908403-0649:S026996482400007X:S026996482400007X_inline6.png\"><span data-mathjax-type=\"texmath\"><span>$X_{1:n}$</span></span></img></span></span> and <span><span><img data-mimesubtype=\"png\" data-type=\"\" src=\"https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240507063908403-0649:S026996482400007X:S026996482400007X_inline7.png\"><span data-mathjax-type=\"texmath\"><span>$Y_{1:n}$</span></span></img></span></span> and <span><span><img data-mimesubtype=\"png\" data-type=\"\" src=\"https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240507063908403-0649:S026996482400007X:S026996482400007X_inline8.png\"><span data-mathjax-type=\"texmath\"><span>$X_{n:n}$</span></span></img></span></span> and <span><span><img data-mimesubtype=\"png\" data-type=\"\" src=\"https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240507063908403-0649:S026996482400007X:S026996482400007X_inline9.png\"><span data-mathjax-type=\"texmath\"><span>$Y_{n:n}$</span></span></img></span></span>, in terms of the usual stochastic, star, Lorenz, hazard rate, reversed hazar","PeriodicalId":54582,"journal":{"name":"Probability in the Engineering and Informational Sciences","volume":"51 1","pages":""},"PeriodicalIF":1.1,"publicationDate":"2024-05-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140884164","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-04-18DOI: 10.1017/s0269964824000044
Bora Çekyay
We focus on exponential semi-Markov decision processes with unbounded transition rates. We first provide several sufficient conditions under which the value iteration procedure converges to the optimal value function and optimal deterministic stationary policies exist. These conditions are also valid for general semi-Markov decision processes possibly with accumulation points. Then, we apply our results to a service rate control problem with impatient customers. The resulting exponential semi-Markov decision process has unbounded transition rates, which makes the well-known uniformization technique inapplicable. We analyze the structure of the optimal policy and the monotonicity of the optimal value function by using the customization technique that was introduced by the author in prior work.
{"title":"Discounted cost exponential semi-Markov decision processes with unbounded transition rates: a service rate control problem with impatient customers","authors":"Bora Çekyay","doi":"10.1017/s0269964824000044","DOIUrl":"https://doi.org/10.1017/s0269964824000044","url":null,"abstract":"<p>We focus on exponential semi-Markov decision processes with unbounded transition rates. We first provide several sufficient conditions under which the value iteration procedure converges to the optimal value function and optimal deterministic stationary policies exist. These conditions are also valid for general semi-Markov decision processes possibly with accumulation points. Then, we apply our results to a service rate control problem with impatient customers. The resulting exponential semi-Markov decision process has unbounded transition rates, which makes the well-known uniformization technique inapplicable. We analyze the structure of the optimal policy and the monotonicity of the optimal value function by using the customization technique that was introduced by the author in prior work.</p>","PeriodicalId":54582,"journal":{"name":"Probability in the Engineering and Informational Sciences","volume":"30 1","pages":""},"PeriodicalIF":1.1,"publicationDate":"2024-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140609514","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-03-19DOI: 10.1017/s0269964824000032
Hui Gao, Chuancun Yin
This paper considers the first passage times to constant boundaries and the two-sided exit problem for Lévy process with a characteristic exponent in which at least one of the two jumps having rational Laplace transforms. The joint distribution of the first passage times and undershoot/overshoot are obtained. The processes recover many models that have appeared in the literature such as the compound Poisson risk models, the perturbed compound Poisson risk models, and their dual ones. As applications, we obtain the solutions for popular path-dependent options such as lookback and barrier options in terms of Laplace transforms.
{"title":"Discounted densities of overshoot and undershoot for Lévy processes with applications in finance","authors":"Hui Gao, Chuancun Yin","doi":"10.1017/s0269964824000032","DOIUrl":"https://doi.org/10.1017/s0269964824000032","url":null,"abstract":"This paper considers the first passage times to constant boundaries and the two-sided exit problem for Lévy process with a characteristic exponent in which at least one of the two jumps having rational Laplace transforms. The joint distribution of the first passage times and undershoot/overshoot are obtained. The processes recover many models that have appeared in the literature such as the compound Poisson risk models, the perturbed compound Poisson risk models, and their dual ones. As applications, we obtain the solutions for popular path-dependent options such as lookback and barrier options in terms of Laplace transforms.","PeriodicalId":54582,"journal":{"name":"Probability in the Engineering and Informational Sciences","volume":"59 1","pages":""},"PeriodicalIF":1.1,"publicationDate":"2024-03-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140165478","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-03-05DOI: 10.1017/s0269964824000020
Qingyuan Guan, Bing Xing Wang
In this paper, the ordering properties of convex and increasing convex orders of the dependent random variables are studied. Some closure properties of the convex and increasing convex orders under independent random variables are extended to the dependent random variables under the Archimedean copula. Two applications are provided to illustrate our results.
{"title":"Some properties of convex and increasing convex orders under Archimedean copula","authors":"Qingyuan Guan, Bing Xing Wang","doi":"10.1017/s0269964824000020","DOIUrl":"https://doi.org/10.1017/s0269964824000020","url":null,"abstract":"<p>In this paper, the ordering properties of convex and increasing convex orders of the dependent random variables are studied. Some closure properties of the convex and increasing convex orders under independent random variables are extended to the dependent random variables under the Archimedean copula. Two applications are provided to illustrate our results.</p>","PeriodicalId":54582,"journal":{"name":"Probability in the Engineering and Informational Sciences","volume":"1 1","pages":""},"PeriodicalIF":1.1,"publicationDate":"2024-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140034523","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-02-16DOI: 10.1017/s0269964824000019
Murat Ozkut, Cihangir Kan, Ceki Franko
A system experiences random shocks over time, with two critical levels, d1 and d2, where $d_{1} lt d_{2}$. k consecutive shocks with magnitudes between d1 and d2 partially damaging the system, causing it to transition to a lower, partially working state. Shocks with magnitudes above d2 have a catastrophic effect, resulting in complete failure. This theoretical framework gives rise to a multi-state system characterized by an indeterminate quantity of states. When the time between successive shocks follows a phase-type distribution, a detailed analysis of the system’s dynamic reliability properties such as the lifetime of the system, the time it spends in perfect functioning, as well as the total time it spends in partially working states are discussed.
{"title":"Analyzing the multi-state system under a run shock model","authors":"Murat Ozkut, Cihangir Kan, Ceki Franko","doi":"10.1017/s0269964824000019","DOIUrl":"https://doi.org/10.1017/s0269964824000019","url":null,"abstract":"A system experiences random shocks over time, with two critical levels, <jats:italic>d</jats:italic><jats:sub>1</jats:sub> and <jats:italic>d</jats:italic><jats:sub>2</jats:sub>, where <jats:inline-formula> <jats:alternatives> <jats:inline-graphic xmlns:xlink=\"http://www.w3.org/1999/xlink\" mime-subtype=\"png\" mimetype=\"image\" xlink:href=\"S0269964824000019_inline1.png\" /> <jats:tex-math>$d_{1} lt d_{2}$</jats:tex-math> </jats:alternatives> </jats:inline-formula>. <jats:italic>k</jats:italic> consecutive shocks with magnitudes between <jats:italic>d</jats:italic><jats:sub>1</jats:sub> and <jats:italic>d</jats:italic><jats:sub>2</jats:sub> partially damaging the system, causing it to transition to a lower, partially working state. Shocks with magnitudes above <jats:italic>d</jats:italic><jats:sub>2</jats:sub> have a catastrophic effect, resulting in complete failure. This theoretical framework gives rise to a multi-state system characterized by an indeterminate quantity of states. When the time between successive shocks follows a phase-type distribution, a detailed analysis of the system’s dynamic reliability properties such as the lifetime of the system, the time it spends in perfect functioning, as well as the total time it spends in partially working states are discussed.","PeriodicalId":54582,"journal":{"name":"Probability in the Engineering and Informational Sciences","volume":"59 1","pages":""},"PeriodicalIF":1.1,"publicationDate":"2024-02-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139769316","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-02-07DOI: 10.1017/s0269964823000207
Félix Balado, Guénolé C. M. Silvestre
We provide general expressions for the joint distributions of the k most significant b-ary digits and of the k leading continued fraction (CF) coefficients of outcomes of arbitrary continuous random variables. Our analysis highlights the connections between the two problems. In particular, we give the general convergence law of the distribution of the jth significant digit, which is the counterpart of the general convergence law of the distribution of the jth CF coefficient (Gauss-Kuz’min law). We also particularise our general results for Benford and Pareto random variables. The former particularisation allows us to show the central role played by Benford variables in the asymptotics of the general expressions, among several other results, including the analogue of Benford’s law for CFs. The particularisation for Pareto variables—which include Benford variables as a special case—is especially relevant in the context of pervasive scale-invariant phenomena, where Pareto variables occur much more frequently than Benford variables. This suggests that the Pareto expressions that we produce have wider applicability than their Benford counterparts in modelling most significant digits and leading CF coefficients of real data. Our results may find practical application in all areas where Benford’s law has been previously used.
我们提供了任意连续随机变量结果的 k 个最重要 bary 数字和 k 个前导连续分数 (CF) 系数联合分布的一般表达式。我们的分析强调了这两个问题之间的联系。特别是,我们给出了第 j 个有效数字分布的一般收敛规律,它与第 j 个 CF 系数分布的一般收敛规律(高斯-库兹明规律)相对应。我们还对本福德随机变量和帕累托随机变量的一般结果进行了特殊化。前者的特殊化使我们能够展示本福德变量在一般表达式渐近中的核心作用,以及其他一些结果,包括 CF 的本福德定律类似物。帕累托变量的特殊化--其中包括作为特例的本福德变量--与普遍的规模不变现象尤其相关,因为帕累托变量比本福德变量出现得更频繁。这表明,在模拟真实数据的最显著位数和前导 CF 系数时,我们得出的帕累托表达式比其对应的本福德表达式具有更广泛的适用性。我们的结果可以实际应用于以前使用本福德定律的所有领域。
{"title":"General distributions of number representation elements","authors":"Félix Balado, Guénolé C. M. Silvestre","doi":"10.1017/s0269964823000207","DOIUrl":"https://doi.org/10.1017/s0269964823000207","url":null,"abstract":"We provide general expressions for the joint distributions of the <jats:italic>k</jats:italic> most significant <jats:italic>b</jats:italic>-ary digits and of the <jats:italic>k</jats:italic> leading continued fraction (CF) coefficients of outcomes of arbitrary continuous random variables. Our analysis highlights the connections between the two problems. In particular, we give the general convergence law of the distribution of the <jats:italic>j</jats:italic>th significant digit, which is the counterpart of the general convergence law of the distribution of the <jats:italic>j</jats:italic>th CF coefficient (Gauss-Kuz’min law). We also particularise our general results for Benford and Pareto random variables. The former particularisation allows us to show the central role played by Benford variables in the asymptotics of the general expressions, among several other results, including the analogue of Benford’s law for CFs. The particularisation for Pareto variables—which include Benford variables as a special case—is especially relevant in the context of pervasive scale-invariant phenomena, where Pareto variables occur much more frequently than Benford variables. This suggests that the Pareto expressions that we produce have wider applicability than their Benford counterparts in modelling most significant digits and leading CF coefficients of real data. Our results may find practical application in all areas where Benford’s law has been previously used.","PeriodicalId":54582,"journal":{"name":"Probability in the Engineering and Informational Sciences","volume":"7 1","pages":""},"PeriodicalIF":1.1,"publicationDate":"2024-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139768952","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-01-29DOI: 10.1017/s0269964823000293
Wanwan Xia, Wenhua Lv
In this paper, we compare the entropy of the original distribution and its corresponding compound distribution. Several results are established based on convex order and relative log-concave order. The necessary and sufficient condition for a compound distribution to be log-concave is also discussed, including compound geometric distribution, compound negative binomial distribution and compound binomial distribution.
{"title":"Log-concavity and relative log-concave ordering of compound distributions","authors":"Wanwan Xia, Wenhua Lv","doi":"10.1017/s0269964823000293","DOIUrl":"https://doi.org/10.1017/s0269964823000293","url":null,"abstract":"In this paper, we compare the entropy of the original distribution and its corresponding compound distribution. Several results are established based on convex order and relative log-concave order. The necessary and sufficient condition for a compound distribution to be log-concave is also discussed, including compound geometric distribution, compound negative binomial distribution and compound binomial distribution.","PeriodicalId":54582,"journal":{"name":"Probability in the Engineering and Informational Sciences","volume":"11 1","pages":""},"PeriodicalIF":1.1,"publicationDate":"2024-01-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139579048","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-01-16DOI: 10.1017/s0269964823000256
Claude Lefèvre, Matthieu Simon
We consider the propagation of a stochastic SIR-type epidemic in two connected populations: a relatively small local population of interest which is surrounded by a much larger external population. External infectives can temporarily enter the small population and contribute to the spread of the infection inside this population. The rules for entry of infectives into the small population as well as their length of stay are modeled by a general Markov queueing system. Our main objective is to determine the distribution of the total number of infections within both populations. To do this, the approach we propose consists of deriving a family of martingales for the joint epidemic processes and applying classical stopping time or convergence theorems. The study then focuses on several particular cases where the external infection is described by a linear branching process and the entry of external infectives obeys certain specific rules. Some of the results obtained are illustrated by numerical examples.
我们考虑的是随机 SIR 型流行病在两个相连种群中的传播问题:一个相对较小的本地相关种群被一个大得多的外部种群所包围。外部感染者可以暂时进入小种群,并促进感染在该种群内部的传播。感染者进入小群体的规则及其停留时间由一般马尔可夫排队系统建模。我们的主要目标是确定两个人群中感染者总数的分布情况。为此,我们提出的方法包括为联合流行过程推导出一系列马氏过程,并应用经典的停止时间或收敛定理。然后,研究将重点放在外部感染由线性分支过程描述且外部感染者的进入遵守某些特定规则的几种特殊情况上。一些结果通过数值示例进行了说明。
{"title":"A queueing system with an SIR-type infection","authors":"Claude Lefèvre, Matthieu Simon","doi":"10.1017/s0269964823000256","DOIUrl":"https://doi.org/10.1017/s0269964823000256","url":null,"abstract":"<p>We consider the propagation of a stochastic SIR-type epidemic in two connected populations: a relatively small local population of interest which is surrounded by a much larger external population. External infectives can temporarily enter the small population and contribute to the spread of the infection inside this population. The rules for entry of infectives into the small population as well as their length of stay are modeled by a general Markov queueing system. Our main objective is to determine the distribution of the total number of infections within both populations. To do this, the approach we propose consists of deriving a family of martingales for the joint epidemic processes and applying classical stopping time or convergence theorems. The study then focuses on several particular cases where the external infection is described by a linear branching process and the entry of external infectives obeys certain specific rules. Some of the results obtained are illustrated by numerical examples.</p>","PeriodicalId":54582,"journal":{"name":"Probability in the Engineering and Informational Sciences","volume":"11 1","pages":""},"PeriodicalIF":1.1,"publicationDate":"2024-01-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139476167","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-01-12DOI: 10.1017/s026996482300027x
Wanyang Dai
We study 2-stage game-theoretic problem oriented 3-stage service policy computing, convolutional neural network (CNN) based algorithm design, and simulation for a blockchained buffering system with federated learning. More precisely, based on the game-theoretic problem consisting of both “win-lose” and “win-win” 2-stage competitions, we derive a 3-stage dynamical service policy via a saddle point to a zero-sum game problem and a Nash equilibrium point to a non-zero-sum game problem. This policy is concerning users-selection, dynamic pricing, and online rate resource allocation via stable digital currency for the system. The main focus is on the design and analysis of the joint 3-stage service policy for given queue/environment state dependent pricing and utility functions. The asymptotic optimality and fairness of this dynamic service policy is justified by diffusion modeling with approximation theory. A general CNN based policy computing algorithm flow chart along the line of the so-called big model framework is presented. Simulation case studies are conducted for the system with three users, where only two of the three users can be selected into the service by a zero-sum dual cost game competition policy at a time point. Then, the selected two users get into service and share the system rate service resource through a non-zero-sum dual cost game competition policy. Applications of our policy in the future blockchain based Internet (e.g., metaverse and web3.0) and supply chain finance are also briefly illustrated.
{"title":"Game-theoretic policy computing and simulation for blockchained buffering system via diffusion approximation","authors":"Wanyang Dai","doi":"10.1017/s026996482300027x","DOIUrl":"https://doi.org/10.1017/s026996482300027x","url":null,"abstract":"We study 2-stage game-theoretic problem oriented 3-stage service policy computing, convolutional neural network (CNN) based algorithm design, and simulation for a blockchained buffering system with federated learning. More precisely, based on the game-theoretic problem consisting of both <jats:italic>“win-lose”</jats:italic> and <jats:italic>“win-win”</jats:italic> 2-stage competitions, we derive a 3-stage dynamical service policy via a saddle point to a zero-sum game problem and a Nash equilibrium point to a non-zero-sum game problem. This policy is concerning users-selection, dynamic pricing, and online rate resource allocation via stable digital currency for the system. The main focus is on the design and analysis of the joint 3-stage service policy for given queue/environment state dependent pricing and utility functions. The asymptotic optimality and fairness of this dynamic service policy is justified by diffusion modeling with approximation theory. A general CNN based policy computing algorithm flow chart along the line of the so-called <jats:italic>big model</jats:italic> framework is presented. Simulation case studies are conducted for the system with three users, where only two of the three users can be selected into the service by a zero-sum dual cost game competition policy at a time point. Then, the selected two users get into service and share the system rate service resource through a non-zero-sum dual cost game competition policy. Applications of our policy in the future blockchain based Internet (e.g., metaverse and web3.0) and supply chain finance are also briefly illustrated.","PeriodicalId":54582,"journal":{"name":"Probability in the Engineering and Informational Sciences","volume":"129 1","pages":""},"PeriodicalIF":1.1,"publicationDate":"2024-01-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139464797","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}