Pub Date : 2025-10-16DOI: 10.1016/j.spa.2025.104795
Jules Berry , Fausto Colantoni
In this paper, we investigate continuous diffusions on star graphs with sticky behaviour at the vertex. These are Markov processes with continuous paths having a positive occupation time at the vertex. We characterize the sticky diffusions as time changed nonsticky diffusions by adapting the classical technique of Itô and McKean. We prove a form of Itô formula, also known as Freidlin–Sheu formula, for this type of process. As an intermediate step, we also obtain a stochastic differential equation satisfied by the radial component of the process. These results generalize those already known for sticky diffusions on a half-line and skew sticky diffusions on the real line.
{"title":"Sticky diffusions on star graphs: Characterization and Itô formula","authors":"Jules Berry , Fausto Colantoni","doi":"10.1016/j.spa.2025.104795","DOIUrl":"10.1016/j.spa.2025.104795","url":null,"abstract":"<div><div>In this paper, we investigate continuous diffusions on star graphs with sticky behaviour at the vertex. These are Markov processes with continuous paths having a positive occupation time at the vertex. We characterize the sticky diffusions as time changed nonsticky diffusions by adapting the classical technique of Itô and McKean. We prove a form of Itô formula, also known as Freidlin–Sheu formula, for this type of process. As an intermediate step, we also obtain a stochastic differential equation satisfied by the radial component of the process. These results generalize those already known for sticky diffusions on a half-line and skew sticky diffusions on the real line.</div></div>","PeriodicalId":51160,"journal":{"name":"Stochastic Processes and their Applications","volume":"192 ","pages":"Article 104795"},"PeriodicalIF":1.2,"publicationDate":"2025-10-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145326464","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-10-16DOI: 10.1016/j.spa.2025.104794
Diego Goldsztajn , Sem C. Borst , Johan S.H. van Leeuwaarden
Consider a network of single-server queues where tasks arrive independently at each server at rate . The servers are connected by a graph that is resampled at rate in a way that is symmetric with respect to the servers, and each task is dispatched to the shortest queue in the graph neighborhood where it appears. We aim to gain insight in the impact of the dynamic network structure on the load balancing dynamics in terms of the occupancy process which describes the empirical distribution of the number of tasks across the servers. This process evolves on the underlying dynamic graph, and its dynamics depend on the number of tasks at each individual server and the neighborhood structure of the graph. We establish that this dependency disappears in the limit as when and , and prove that the limit of the occupancy process is given by a system of differential equations that depends solely on and the limiting degree distribution of the graph. We further show that the stationary distribution of the occupancy process converges to an equilibrium of the differential equations, and derive properties of this equilibrium that reflect the impact of the degree distribution. Our focus is on truly sparse graphs where the maximum degree is uniformly bounded across , which is natural in load balancing systems.
{"title":"Fluid limits for interacting queues in sparse dynamic graphs","authors":"Diego Goldsztajn , Sem C. Borst , Johan S.H. van Leeuwaarden","doi":"10.1016/j.spa.2025.104794","DOIUrl":"10.1016/j.spa.2025.104794","url":null,"abstract":"<div><div>Consider a network of <span><math><mi>n</mi></math></span> single-server queues where tasks arrive independently at each server at rate <span><math><msub><mrow><mi>λ</mi></mrow><mrow><mi>n</mi></mrow></msub></math></span>. The servers are connected by a graph that is resampled at rate <span><math><msub><mrow><mi>μ</mi></mrow><mrow><mi>n</mi></mrow></msub></math></span> in a way that is symmetric with respect to the servers, and each task is dispatched to the shortest queue in the graph neighborhood where it appears. We aim to gain insight in the impact of the dynamic network structure on the load balancing dynamics in terms of the occupancy process which describes the empirical distribution of the number of tasks across the servers. This process evolves on the underlying dynamic graph, and its dynamics depend on the number of tasks at each individual server and the neighborhood structure of the graph. We establish that this dependency disappears in the limit as <span><math><mrow><mi>n</mi><mo>→</mo><mi>∞</mi></mrow></math></span> when <span><math><mrow><msub><mrow><mi>λ</mi></mrow><mrow><mi>n</mi></mrow></msub><mo>/</mo><mi>n</mi><mo>→</mo><mi>λ</mi></mrow></math></span> and <span><math><mrow><msub><mrow><mi>μ</mi></mrow><mrow><mi>n</mi></mrow></msub><mo>→</mo><mi>∞</mi></mrow></math></span>, and prove that the limit of the occupancy process is given by a system of differential equations that depends solely on <span><math><mi>λ</mi></math></span> and the limiting degree distribution of the graph. We further show that the stationary distribution of the occupancy process converges to an equilibrium of the differential equations, and derive properties of this equilibrium that reflect the impact of the degree distribution. Our focus is on truly sparse graphs where the maximum degree is uniformly bounded across <span><math><mi>n</mi></math></span>, which is natural in load balancing systems.</div></div>","PeriodicalId":51160,"journal":{"name":"Stochastic Processes and their Applications","volume":"192 ","pages":"Article 104794"},"PeriodicalIF":1.2,"publicationDate":"2025-10-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145326463","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-10-14DOI: 10.1016/j.spa.2025.104793
Oleksii Galganov , Andrii Ilienko
The Chinese restaurant process is a basic sequential construction of consistent random partitions. We consider random point measures describing the composition of small blocks in such partitions and show that their scaling limit is given by the projective limit of certain inhomogeneous Poisson measures on cones of increasing dimension. This result makes it possible to derive classical and functional limit theorems in the Skorokhod topology for various characteristics of the Chinese restaurant process.
{"title":"Scaling limit for small blocks in the Chinese restaurant process","authors":"Oleksii Galganov , Andrii Ilienko","doi":"10.1016/j.spa.2025.104793","DOIUrl":"10.1016/j.spa.2025.104793","url":null,"abstract":"<div><div>The Chinese restaurant process is a basic sequential construction of consistent random partitions. We consider random point measures describing the composition of small blocks in such partitions and show that their scaling limit is given by the projective limit of certain inhomogeneous Poisson measures on cones of increasing dimension. This result makes it possible to derive classical and functional limit theorems in the Skorokhod topology for various characteristics of the Chinese restaurant process.</div></div>","PeriodicalId":51160,"journal":{"name":"Stochastic Processes and their Applications","volume":"192 ","pages":"Article 104793"},"PeriodicalIF":1.2,"publicationDate":"2025-10-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145326462","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-10-13DOI: 10.1016/j.spa.2025.104779
Mathias Beiglböck , Gudmund Pammer , Lorenz Riess
Change of numeraire is a classical tool in mathematical finance. Campi–Laachir–Martini (Campi et al., 2017) established its applicability to martingale optimal transport. We note that the results of Campi et al. (2017) extend to the case of weak martingale transport. We apply this to shadow couplings (in the sense of Beiglböck and Juillet (2021)), continuous time martingale transport problems in the framework of Huesmann–Trevisan (Huesmann and Trevisan, 2019) and in particular to establish the correspondence of stretched Brownian motion with its geometric counterpart. From a mathematical finance perspective, the geometric (stretched) Brownian motion and the corresponding geometric Bass local volatility model are more natural, and via the change of numeraire transform the efficient and well-understood algorithm for the Bass local volatility model can be adapted to this geometric counterpart.
数值变换是数学金融中的一种经典工具。Campi - laachir - martini (Campi et al., 2017)建立了其对鞅最优运输的适用性。我们注意到Campi等人(2017)的结果扩展到弱鞅输运的情况。我们将其应用于阴影耦合(Beiglböck和juliet(2021)的意义上),Huesmann - Trevisan框架中的连续时间矩阵输移问题(Huesmann和Trevisan, 2019),特别是建立拉伸布朗运动与其几何对应的对应关系。从数学金融的角度来看,几何(拉伸)布朗运动和相应的几何Bass局部波动模型更自然,通过改变数值变换,Bass局部波动模型的高效且易于理解的算法可以适应于这种几何对应物。
{"title":"Change of numeraire for weak martingale transport","authors":"Mathias Beiglböck , Gudmund Pammer , Lorenz Riess","doi":"10.1016/j.spa.2025.104779","DOIUrl":"10.1016/j.spa.2025.104779","url":null,"abstract":"<div><div>Change of numeraire is a classical tool in mathematical finance. Campi–Laachir–Martini (Campi et al., 2017) established its applicability to martingale optimal transport. We note that the results of Campi et al. (2017) extend to the case of weak martingale transport. We apply this to shadow couplings (in the sense of Beiglböck and Juillet (2021)), continuous time martingale transport problems in the framework of Huesmann–Trevisan (Huesmann and Trevisan, 2019) and in particular to establish the correspondence of stretched Brownian motion with its geometric counterpart. From a mathematical finance perspective, the geometric (stretched) Brownian motion and the corresponding geometric Bass local volatility model are more natural, and via the change of numeraire transform the efficient and well-understood algorithm for the Bass local volatility model can be adapted to this geometric counterpart.</div></div>","PeriodicalId":51160,"journal":{"name":"Stochastic Processes and their Applications","volume":"192 ","pages":"Article 104779"},"PeriodicalIF":1.2,"publicationDate":"2025-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145467325","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-10-11DOI: 10.1016/j.spa.2025.104791
Leo Hahn
We study the long-time behavior of two run-and-tumble particles on the real line subjected to an attractive interaction potential and jamming interactions, which prevent the particles from crossing. We provide the explicit invariant measure, a useful tool for studying clustering phenomena in out-of-equilibrium statistical mechanics, for different tumbling mechanisms and potentials. An important difference with invariant measures of equilibrium systems are Dirac masses on the boundary of the state space, due to the jamming interactions. Qualitative changes in the invariant measure depending on model parameters are also observed, suggesting, like a growing body of evidence, that run-and-tumble particle systems can be classified into close-to-equilibrium and strongly out-of-equilibrium models. We also study the relaxation properties of the system, which are linked to the timescale at which clustering emerges from an arbitrary initial configuration. When the interaction potential is linear, we show that the total variation distance to the invariant measure decays exponentially and provide sharp bounds on the decay rate. When the interaction potential is harmonic, we give quantitative exponential bounds in a Wasserstein-type distance.
{"title":"Steady state and mixing of two run-and-tumble particles interacting through jamming and attractive forces","authors":"Leo Hahn","doi":"10.1016/j.spa.2025.104791","DOIUrl":"10.1016/j.spa.2025.104791","url":null,"abstract":"<div><div>We study the long-time behavior of two run-and-tumble particles on the real line subjected to an attractive interaction potential and jamming interactions, which prevent the particles from crossing. We provide the explicit invariant measure, a useful tool for studying clustering phenomena in out-of-equilibrium statistical mechanics, for different tumbling mechanisms and potentials. An important difference with invariant measures of equilibrium systems are Dirac masses on the boundary of the state space, due to the jamming interactions. Qualitative changes in the invariant measure depending on model parameters are also observed, suggesting, like a growing body of evidence, that run-and-tumble particle systems can be classified into close-to-equilibrium and strongly out-of-equilibrium models. We also study the relaxation properties of the system, which are linked to the timescale at which clustering emerges from an arbitrary initial configuration. When the interaction potential is linear, we show that the total variation distance to the invariant measure decays exponentially and provide sharp bounds on the decay rate. When the interaction potential is harmonic, we give quantitative exponential bounds in a Wasserstein-type distance.</div></div>","PeriodicalId":51160,"journal":{"name":"Stochastic Processes and their Applications","volume":"192 ","pages":"Article 104791"},"PeriodicalIF":1.2,"publicationDate":"2025-10-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145326465","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-10-10DOI: 10.1016/j.spa.2025.104788
Thomas Cavallazzi
We prove Itô’s formula for the flow of measures associated with a jump process defined by a drift, an integral with respect to a Poisson random measure and with respect to the associated compensated Poisson random measure. We work in , the space of probability measures on having a finite moment of order . As an application, we exhibit the backward Kolmogorov partial differential equation stated on associated with a McKean–Vlasov stochastic differential equation driven by a Poisson random measure. It describes the dynamics of the semigroup acting on functions defined on associated with the McKean–Vlasov stochastic differential equation, under regularity assumptions on it. Finally, we use the semigroup and the backward Kolmogorov equation to prove new quantitative weak propagation of chaos results for a mean-field system of interacting Ornstein–Uhlenbeck processes driven by i.i.d. -stable processes with .
{"title":"Itô’s formula for the flow of measures of Poisson stochastic integrals and applications","authors":"Thomas Cavallazzi","doi":"10.1016/j.spa.2025.104788","DOIUrl":"10.1016/j.spa.2025.104788","url":null,"abstract":"<div><div>We prove Itô’s formula for the flow of measures associated with a jump process defined by a drift, an integral with respect to a Poisson random measure and with respect to the associated compensated Poisson random measure. We work in <span><math><mrow><msub><mrow><mi>P</mi></mrow><mrow><mi>β</mi></mrow></msub><mrow><mo>(</mo><msup><mrow><mi>R</mi></mrow><mrow><mi>d</mi></mrow></msup><mo>)</mo></mrow></mrow></math></span>, the space of probability measures on <span><math><msup><mrow><mi>R</mi></mrow><mrow><mi>d</mi></mrow></msup></math></span> having a finite moment of order <span><math><mrow><mi>β</mi><mo>∈</mo><mrow><mo>(</mo><mn>0</mn><mo>,</mo><mn>2</mn><mo>]</mo></mrow></mrow></math></span>. As an application, we exhibit the backward Kolmogorov partial differential equation stated on <span><math><mrow><mrow><mo>[</mo><mn>0</mn><mo>,</mo><mi>T</mi><mo>]</mo></mrow><mo>×</mo><msub><mrow><mi>P</mi></mrow><mrow><mi>β</mi></mrow></msub><mrow><mo>(</mo><msup><mrow><mi>R</mi></mrow><mrow><mi>d</mi></mrow></msup><mo>)</mo></mrow></mrow></math></span> associated with a McKean–Vlasov stochastic differential equation driven by a Poisson random measure. It describes the dynamics of the semigroup acting on functions defined on <span><math><mrow><msub><mrow><mi>P</mi></mrow><mrow><mi>β</mi></mrow></msub><mrow><mo>(</mo><msup><mrow><mi>R</mi></mrow><mrow><mi>d</mi></mrow></msup><mo>)</mo></mrow></mrow></math></span> associated with the McKean–Vlasov stochastic differential equation, under regularity assumptions on it. Finally, we use the semigroup and the backward Kolmogorov equation to prove new quantitative weak propagation of chaos results for a mean-field system of interacting Ornstein–Uhlenbeck processes driven by i.i.d. <span><math><mi>α</mi></math></span>-stable processes with <span><math><mrow><mi>α</mi><mo>∈</mo><mrow><mo>(</mo><mn>1</mn><mo>,</mo><mn>2</mn><mo>)</mo></mrow></mrow></math></span>.</div></div>","PeriodicalId":51160,"journal":{"name":"Stochastic Processes and their Applications","volume":"192 ","pages":"Article 104788"},"PeriodicalIF":1.2,"publicationDate":"2025-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145326388","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-10-04DOI: 10.1016/j.spa.2025.104785
M. Aleandri , P. Dai Pra
A dynamical system that undergoes a supercritical Hopf’s bifurcation is perturbed by a multiplicative Brownian motion that scales with a small parameter . The random fluctuations of the system at the critical point are studied when the dynamics starts near equilibrium, in the limit as goes to zero. Under a space–time scaling the system can be approximated by a 2-dimensional process lying on the center manifold of the Hopf’s bifurcation and a slow radial component together with a fast angular component are identified. Then the critical fluctuations are described by a “universal” stochastic differential equation whose coefficients are obtained taking the average with respect to the fast variable.
{"title":"Long time fluctuations at critical parameter of Hopf’s bifurcation","authors":"M. Aleandri , P. Dai Pra","doi":"10.1016/j.spa.2025.104785","DOIUrl":"10.1016/j.spa.2025.104785","url":null,"abstract":"<div><div>A dynamical system that undergoes a supercritical Hopf’s bifurcation is perturbed by a multiplicative Brownian motion that scales with a small parameter <span><math><mi>ɛ</mi></math></span>. The random fluctuations of the system at the critical point are studied when the dynamics starts near equilibrium, in the limit as <span><math><mi>ɛ</mi></math></span> goes to zero. Under a space–time scaling the system can be approximated by a 2-dimensional process lying on the center manifold of the Hopf’s bifurcation and a slow radial component together with a fast angular component are identified. Then the critical fluctuations are described by a “universal” stochastic differential equation whose coefficients are obtained taking the average with respect to the fast variable.</div></div>","PeriodicalId":51160,"journal":{"name":"Stochastic Processes and their Applications","volume":"192 ","pages":"Article 104785"},"PeriodicalIF":1.2,"publicationDate":"2025-10-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145247888","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-10-04DOI: 10.1016/j.spa.2025.104787
Takumu Ooi
We provide necessary and sufficient conditions for the convergence of Revuz measures of finite energy integrals. More precisely, the Revuz map from the set of all smooth measures of finite energy integrals, equipped with the topology induced by the norm given by the sum of the Dirichlet form and the -norm, to the space of positive continuous additive functionals, equipped with the topology induced by the -norm with the local uniform topology, is a homeomorphism, where is the underlying measure, is the killing measure of a Dirichlet form and is an energy functional corresponding to the part of the process that continuously escapes to the cemetery point.
{"title":"Homeomorphism of the Revuz correspondence for finite energy integrals","authors":"Takumu Ooi","doi":"10.1016/j.spa.2025.104787","DOIUrl":"10.1016/j.spa.2025.104787","url":null,"abstract":"<div><div>We provide necessary and sufficient conditions for the convergence of Revuz measures of finite energy integrals. More precisely, the Revuz map from the set of all smooth measures of finite energy integrals, equipped with the topology induced by the norm given by the sum of the Dirichlet form and the <span><math><mrow><msup><mrow><mi>L</mi></mrow><mrow><mn>2</mn></mrow></msup><mrow><mo>(</mo><mi>m</mi><mo>)</mo></mrow></mrow></math></span>-norm, to the space of positive continuous additive functionals, equipped with the topology induced by the <span><math><mrow><msup><mrow><mi>L</mi></mrow><mrow><mn>2</mn></mrow></msup><mrow><mo>(</mo><msub><mrow><mi>P</mi></mrow><mrow><mi>m</mi><mo>+</mo><mi>κ</mi><mo>+</mo><msub><mrow><mi>ν</mi></mrow><mrow><mn>0</mn></mrow></msub></mrow></msub><mo>)</mo></mrow></mrow></math></span>-norm with the local uniform topology, is a homeomorphism, where <span><math><mi>m</mi></math></span> is the underlying measure, <span><math><mi>κ</mi></math></span> is the killing measure of a Dirichlet form and <span><math><msub><mrow><mi>ν</mi></mrow><mrow><mn>0</mn></mrow></msub></math></span> is an energy functional corresponding to the part of the process that continuously escapes to the cemetery point.</div></div>","PeriodicalId":51160,"journal":{"name":"Stochastic Processes and their Applications","volume":"191 ","pages":"Article 104787"},"PeriodicalIF":1.2,"publicationDate":"2025-10-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145269401","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-10-03DOI: 10.1016/j.spa.2025.104786
Tomasz Klimsiak , Maurycy Rzymowski
We study Dynkin games governed by a nonlinear -expectation on a finite interval , with payoff càdlàg processes of class (D) which are not imposed to satisfy (weak) Mokobodzki’s condition – the existence of a càdlàg semimartingale between the barriers. For that purpose we introduce the notion of Mokobodzki’s stochastic intervals (roughly speaking, maximal stochastic interval on which Mokobodzki’s condition is satisfied when starting from the stopping time ) and the notion of reflected BSDEs without Mokobodzki’s condition. We prove an existence and uniqueness result for RBSDEs with driver that is non-increasing with respect to the value variable (no restrictions on the growth) and Lipschitz continuous with respect to the control variable, and with data in spaces. Next, we show numerous results on Dynkin games with most notable saying that the game is not played beyond , when starting from .
{"title":"Mokobodzki’s intervals: An approach to Dynkin games when value process is not a semimartingale","authors":"Tomasz Klimsiak , Maurycy Rzymowski","doi":"10.1016/j.spa.2025.104786","DOIUrl":"10.1016/j.spa.2025.104786","url":null,"abstract":"<div><div>We study Dynkin games governed by a nonlinear <span><math><msup><mrow><mi>E</mi></mrow><mrow><mi>f</mi></mrow></msup></math></span>-expectation on a finite interval <span><math><mrow><mo>[</mo><mn>0</mn><mo>,</mo><mi>T</mi><mo>]</mo></mrow></math></span>, with payoff càdlàg processes <span><math><mrow><mi>L</mi><mo>,</mo><mi>U</mi></mrow></math></span> of class (D) which are not imposed to satisfy (weak) Mokobodzki’s condition – the existence of a càdlàg semimartingale between the barriers. For that purpose we introduce the notion of Mokobodzki’s stochastic intervals <span><math><mrow><mi>ℳ</mi><mrow><mo>(</mo><mi>θ</mi><mo>)</mo></mrow></mrow></math></span> (roughly speaking, maximal stochastic interval on which Mokobodzki’s condition is satisfied when starting from the stopping time <span><math><mi>θ</mi></math></span>) and the notion of reflected BSDEs without Mokobodzki’s condition. We prove an existence and uniqueness result for RBSDEs with driver <span><math><mi>f</mi></math></span> that is non-increasing with respect to the value variable (no restrictions on the growth) and Lipschitz continuous with respect to the control variable, and with data in <span><math><msup><mrow><mi>L</mi></mrow><mrow><mn>1</mn></mrow></msup></math></span> spaces. Next, we show numerous results on Dynkin games with most notable saying that the game is not played beyond <span><math><mrow><mi>ℳ</mi><mrow><mo>(</mo><mi>θ</mi><mo>)</mo></mrow></mrow></math></span>, when starting from <span><math><mi>θ</mi></math></span>.</div></div>","PeriodicalId":51160,"journal":{"name":"Stochastic Processes and their Applications","volume":"191 ","pages":"Article 104786"},"PeriodicalIF":1.2,"publicationDate":"2025-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145269394","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-09-27DOI: 10.1016/j.spa.2025.104784
Yudan Xiong , Fangjun Xu , Jinjiong Yu
Let be the linear process defined by , where the coefficients are constants with and a slowly varying function, and the innovations are i.i.d. random variables belonging to the domain of attraction of an -stable law with . Limit theorems for the partial sum with proper measurable functions have been extensively studied, except for two critical regions: I. and II. . In this paper, we address these open scenarios and identify the asymptotic distributions of under mild conditions.
设X={Xn:n∈n}是由Xn=∑j=1∞aj æ n−j定义的线性过程,其中系数aj=j−β Z (j)是具有β>;0的常数,α∈(0,2)的缓变函数,创新项{æ n}n∈Z是属于α-稳定定律吸引域的i.d个随机变量。具有适当可测函数K的部分和S[Nt]=∑n=1[Nt][K(Xn)−EK(Xn)]的极限定理已经得到了广泛的研究,除了两个临界区域:I. α∈(1,2),β=1和II。αβ= 2,β≥1。在本文中,我们解决了这些开放的情况,并确定了S[Nt]在温和条件下的渐近分布。
{"title":"Limit theorems for functionals of linear processes in critical regions","authors":"Yudan Xiong , Fangjun Xu , Jinjiong Yu","doi":"10.1016/j.spa.2025.104784","DOIUrl":"10.1016/j.spa.2025.104784","url":null,"abstract":"<div><div>Let <span><math><mrow><mi>X</mi><mo>=</mo><mrow><mo>{</mo><msub><mrow><mi>X</mi></mrow><mrow><mi>n</mi></mrow></msub><mo>:</mo><mi>n</mi><mo>∈</mo><mi>N</mi><mo>}</mo></mrow></mrow></math></span> be the linear process defined by <span><math><mrow><msub><mrow><mi>X</mi></mrow><mrow><mi>n</mi></mrow></msub><mo>=</mo><msubsup><mrow><mo>∑</mo></mrow><mrow><mi>j</mi><mo>=</mo><mn>1</mn></mrow><mrow><mi>∞</mi></mrow></msubsup><msub><mrow><mi>a</mi></mrow><mrow><mi>j</mi></mrow></msub><msub><mrow><mi>ɛ</mi></mrow><mrow><mi>n</mi><mo>−</mo><mi>j</mi></mrow></msub></mrow></math></span>, where the coefficients <span><math><mrow><msub><mrow><mi>a</mi></mrow><mrow><mi>j</mi></mrow></msub><mo>=</mo><msup><mrow><mi>j</mi></mrow><mrow><mo>−</mo><mi>β</mi></mrow></msup><mi>ℓ</mi><mrow><mo>(</mo><mi>j</mi><mo>)</mo></mrow></mrow></math></span> are constants with <span><math><mrow><mi>β</mi><mo>></mo><mn>0</mn></mrow></math></span> and <span><math><mi>ℓ</mi></math></span> a slowly varying function, and the innovations <span><math><msub><mrow><mrow><mo>{</mo><msub><mrow><mi>ɛ</mi></mrow><mrow><mi>n</mi></mrow></msub><mo>}</mo></mrow></mrow><mrow><mi>n</mi><mo>∈</mo><mi>Z</mi></mrow></msub></math></span> are i.i.d. random variables belonging to the domain of attraction of an <span><math><mi>α</mi></math></span>-stable law with <span><math><mrow><mi>α</mi><mo>∈</mo><mrow><mo>(</mo><mn>0</mn><mo>,</mo><mn>2</mn><mo>]</mo></mrow></mrow></math></span>. Limit theorems for the partial sum <span><math><mrow><msub><mrow><mi>S</mi></mrow><mrow><mrow><mo>[</mo><mi>N</mi><mi>t</mi><mo>]</mo></mrow></mrow></msub><mo>=</mo><msubsup><mrow><mo>∑</mo></mrow><mrow><mi>n</mi><mo>=</mo><mn>1</mn></mrow><mrow><mrow><mo>[</mo><mi>N</mi><mi>t</mi><mo>]</mo></mrow></mrow></msubsup><mrow><mo>[</mo><mi>K</mi><mrow><mo>(</mo><msub><mrow><mi>X</mi></mrow><mrow><mi>n</mi></mrow></msub><mo>)</mo></mrow><mo>−</mo><mi>E</mi><mi>K</mi><mrow><mo>(</mo><msub><mrow><mi>X</mi></mrow><mrow><mi>n</mi></mrow></msub><mo>)</mo></mrow><mo>]</mo></mrow></mrow></math></span> with proper measurable functions <span><math><mi>K</mi></math></span> have been extensively studied, except for two critical regions: I. <span><math><mrow><mi>α</mi><mo>∈</mo><mrow><mo>(</mo><mn>1</mn><mo>,</mo><mn>2</mn><mo>)</mo></mrow><mo>,</mo><mi>β</mi><mo>=</mo><mn>1</mn></mrow></math></span> and II. <span><math><mrow><mi>α</mi><mi>β</mi><mo>=</mo><mn>2</mn><mo>,</mo><mi>β</mi><mo>≥</mo><mn>1</mn></mrow></math></span>. In this paper, we address these open scenarios and identify the asymptotic distributions of <span><math><msub><mrow><mi>S</mi></mrow><mrow><mrow><mo>[</mo><mi>N</mi><mi>t</mi><mo>]</mo></mrow></mrow></msub></math></span> under mild conditions.</div></div>","PeriodicalId":51160,"journal":{"name":"Stochastic Processes and their Applications","volume":"191 ","pages":"Article 104784"},"PeriodicalIF":1.2,"publicationDate":"2025-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145269400","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}