Random

random@lists.dm.unipi.it

5 participants
5327 discussions

Fwd: International Seminar on SDEs and Related Topics: Laurent Denis - March14
by Gianmario Tessitore - UNIMIB 06 Mar '25

06 Mar '25

Diffondo con piacere Mario ============================================================================ Dear Colleague, *on Friday, March 14,* (12:30 noon London, 1:30 pm Berlin, 2:30 pm Helsinki, 8:30 pm Beijing) in the *International Seminar on SDEs and Related Topics* in Zoom https://jyufi.zoom.us/j/61891007917 *Laurent Denis* (Université du Maine, France) will speak about */BSDE with singular terminal condition: the continuity up to terminal time problem/ * Abstract: We study the limit behavior of the solution of a backward stochastic differential equation when the terminal condition is singular, that is it can be equal to infinity with a positive probability. In the Markovian setting and in the case where the equation is driven by a Brownian motion, Malliavin's calculus enables us to prove continuity if a balance condition between the growth w.r.t. /y/ and the growth w.r.t. /z/ of the generator is satisfied. We apply our result to liquidity problem in finance and to the solution of some semi-linear partial differential equation ; the imposed assumption is also new in the literature on PDE. Finally, we prove that if there are jumps (i.e. the operator of the PDE is non local), we observe a propagation of the singularity, contrary to the continuous case (local operator). This talk is based on several joint works with D. Cacitti-Holland and A. Popier. References: Cacitti-Holland D., Denis L., Popier A. Continuity problem for BSDE and IPDE with singular terminal condition,/Journal of Mathematical Analysis and Applications/, Vol. 543, issue 1 (2025). Cacitti-Holland D., Denis L., Popier A. Growth condition on the generator of BSDE with singular terminal value ensuring continuity up to terminal time, to appear in /Stochastic Processes and their Applications/ (2025). ABOUT THE SPEAKER: Laurent Denis is professor at the mathematical laboratory, LMM, of "Le Mans Université" in France, since 2013. Formerly, he was professor at "Université d’Evry » from 2005 to 2013.He received a PhD in Mathematics from University Paris VI in 1994 under the supervision of F. Hirsch and his habilitation from Le Mans University in 2012. From 2012 to 2023 he was also teaching at Ecole Polytechnique. His research interests are centered around uncertain models in finance, non-linear expectation, Stochastic Partial Differential Equations, Malliavin calculus for jump processes, Dirichlet forms and more recently Backward Stochastic Differential equations.. Besides numerous publications, he is the co-author with N. Bouleau of the monograph "Dirichlet Forms Methods for Poisson Point Measures and Lévy Processes » published in 2017. Welcome in the name of all the organizers Hannah Geiss For the dates and the list of the upcoming speakers go to http://users.jyu.fi/~chgeiss/seminar-on-sdes.html -- Gianmario Tessitore Dipartimento di Matematica e Applicazioni Università degli Studi di Milano-Bicocca

1 0

Reminder to register for SPDEvent 2025
by Umberto PAPPALETTERA 05 Mar '25

05 Mar '25

Dear colleagues, This is a friendly reminder that the deadline for registrations to the SPDEvent 2025 is approaching. If you wish to participate and you haven't already registered and/or applied for funding, please do it now to secure your participation. We look forward to seeing you in Bielefeld! The organizers, Florian Bechtold Stefanie Berkemeier Theresa Lange Eliseo Luongo Umberto Pappalettera

1 0

OWPS is back next week!
by Luisa Andreis 05 Mar '25

05 Mar '25

Dear colleagues, We are delighted to announce that the One World Probability Seminar is returning for the Spring 2025 semester with a refreshed schedule! The seminar will be held every other Wednesday at 14:00 UTC. The season will kick off on Wednesday, March 12 at 14:00 UTC via Zoom (link<https://polimi-it.zoom.us/j/92945513591?pwd=zjtRwpHoO9kRyQuPPj4o186jXrvg1v.1>). We are thrilled to welcome our first two speakers: Shankar Bhamidi (University of North Carolina) and David J. Aldous (UC Berkeley) Please find titles and abstracts of their talks below and on our website<https://www.owprobability.org/about>, which also contains future speakers for the semester. Originally launched during the early days of the pandemic to keep the probability community connected, our seminar has since hosted over 100 research talks from around the globe. It remains open to anyone eager to learn about the latest developments in probability theory. We encourage you to share this announcement as we embark on this new chapter. If you want updates on future OWP seminars, consider joining our mailing list: here<https://www.owprobability.org/mailing-list> the instructions. We look forward to seeing many of you online! Best wishes, Luisa Andreis and Roger Van Peski Aldous’s fringe convergence of random trees and its applications Shankar Bhamidi (UNC Chapel Hill) Local weak convergence starting with the work of Aldous and Benjamini and Schramm has turned out to be one of the standard work horses in modern probabilistic combinatorics, to understand asymptotics of large discrete random structures and dynamics of processes such as random walks on such processes. The goal of this talk is to describe the impact of one of the less well known “OG” (original great) papers in this area: Aldous’s work on fringe convergence of random trees developed in a paper in the mid 90s. This technique, coupled with stochastic approximation techniques allows one to relatively easily prove local weak convergence of a number of modern random tree models proposed by domain scientists, including network evolution with limited choice, network dynamics where new individuals have access to only a partial temporal snapshot of the network and network evolution models where individuals have different attributes. Obscure results and open problems: some of my favorites David J. Aldous (UC Berkeley) These are some problems that I would like some smart young person to work on! (1) What probability distributions on $[0,\infty)$ arise as the distance between two i.i.d. points in some complete separable metric space? (2) Probability distributions on routed planar networks. (3) Combinatorics of fringe trees in a phylogenetic model. (4) Nearest neighbor of nearest neighbor, on the complete network -- Are you smarter than an AI? (5) Find a qualitatively realistic model for a generic subway network. (6) Percolation of empires.

1 0

Seminar Luciano CAMPI
by Antonello Pesce 05 Mar '25

05 Mar '25

Dear all, On March 19th, at the Department of Mathematics of the University of Bologna and online at this LINK <https://teams.microsoft.com/l/meetup-join/19:meeting_ZTI3YTRhYmEtZDhmYi00ZW…>, the following seminar will take place: 11:00-12:00: Luciano CAMPI “CONTINUOUS-TIME PERSUASION BY FILTERING ” as part of the cycle Stochastics and Applications. The abstract is available at https://seminari.dm.unibo.it/mat/seminars/2025/03/19/luciano-campi <https://seminari.dm.unibo.it/mat/seminars/2025/03/19/luciano-campi> For any question, please contact the organizers: Elena Bandini (elena.bandini7(a)unibo.it <mailto:elena.bandini7@unibo.it>), Antonello Pesce (antonello.pesce2(a)unibo.it <mailto:antonello.pesce2@unibo.it>)

1 0

ABS25 (Applied Bayesian Statistics) summer school in Genova, Italy, 3-6/6/2025
by Elisa Varini 05 Mar '25

05 Mar '25

We are pleased to inform you that registration and fee payment are now possible for the next Applied Bayesian Statistics summer school - ABS25 to be held from 3 to 6 June 2025 in the beautiful historic city of Genova, overlooking the Ligurian Sea in Italy. Website: https://abs25.imati.cnr.it/ <https://abs25.imati.cnr.it/> The school is organized by CNR IMATI (Institute of Applied Mathematics and Information Technologies at the Italian National Research Council in Milano), in cooperation with the Department of Mathematics of the University of Genova. The topic will be SPATIO-TEMPORAL METHODS IN ENVIRONMENTAL EPIDEMIOLOGY The lecturer will be Prof. ALEXANDRA SCHMIDT (McGill University, Department of Epidemiology, Biostatistics and Occupational Health, Canada), with the support of Dr. CARLO ZACCARDI (University G. d'Annunzio Chieti-Pescara, Department of Economics, Italy). As in the past (since 2004), there will be a combination of theoretical and practical sessions, along with presentations by participants about their work (past, current and future) related to the topic of the school. OUTLINE: This course aims to explore the interface between environmental epidemiology (EE) and spatio-temporal modelling (ST). The aim of EE is to understand the adverse health effects of environmental hazards and to estimate the risks associated with those hazards. Such risks have traditionally been assessed either over time at a fixed point in space or over space at a fixed point in time. ST modelling characterizes the distribution of those hazards and associated risks over both geographical locations and time. Understanding variation and exploiting dependencies over both space and time greatly increases the power to assess those relationships. The course will cover a wide range of topics from an introduction to spatio-temporal and epidemiological principles along with the foundations of ST modeling, with specific focus on their application, to new directions for research. Topics to be covered: - Types of epidemiological studies: cohort, case–control, ecological - Measures of risk: relative risks, odds ratios, absolute risk, sources of bias, assessing uncertainty - Bayesian statistics and computational techniques: Markov Chain Monte Carlo (MCMC) - Regression models in epidemiology: Logistic and Poisson generalized linear models, hierarchical models - Dynamic linear models, temporal autocorrelation - Spatial models: area and point referenced methods, mapping, geostatistical methods, spatial regression - Spatial-temporal models: separable models, non-separable models, modelling exposures in space and time. Reference: Shaddick, G., Zidek, J.V., & Schmidt, A.M. (2023). Spatio–Temporal Methods in Environmental Epidemiology with R (2nd ed.). Chapman and Hall/CRC. https://doi.org/10.1201/9781003352655 <https://doi.org/10.1201/9781003352655> We hope you will be interested in the school, and we would like to meet you in Genova. We invite you also to share the information with people potentially interested. Best regards Elisa Varini and Fabrizio Ruggeri Executive Director and Director of ABS25

1 0

Seminario Matteo Brachetta - Politecnico di Milano - 13 Marzo 2025
by Luca Scarpa 04 Mar '25

04 Mar '25

Si segnala il seguente seminario a tutti gli interessati. Giovedì 13 Marzo 2025, ore 11:45. Aula Seminari VI Piano, Dipartimento di Matematica, Politecnico di Milano. Speaker: Matteo Brachetta, Università di Genova. Title: Risk measures and optimal reinsurance: finding a connection via BSDEs. Abstract: The aim of this talk is to connect utiility maximization problems and the optimization of dynamic risk measures, which are usually considered as two different branches or approaches to financial problems. A reinsurance contract allows an insurance company to transfer part of the risk to another company, namely the reinsurer, in order to reduce the future losses, which are usually modeled as a marked point process. Finding the optimal reinsurance agreement translates into a stochastic control problem for the insurer. Recently, some authors showed that the optimal value process for the utility maximization problem can be characterized as the solution of a BSDE with jumps. In other works, it is proved that some BSDEs induce dynamic risk measures, which can be financially interpreted as a default time and an associated mark. In this talk we aim to explore the properties of the risk measure induced by the optimal reinsurance policy under dierent risk models with jumps. The talk is based on a work in progress with Fulvia Confortola (Politecnico of Milan). Link Zoom: <https://polimi-it.zoom.us/j/95837122103?pwd=hXtbnj0t8rpSbybIkhGUYwEjZ1dgxN.1> Join our Cloud HD Video Meeting<https://polimi-it.zoom.us/j/95837122103?pwd=hXtbnj0t8rpSbybIkhGUYwEjZ1dgxN.1> polimi-it.zoom.us<https://polimi-it.zoom.us/j/95837122103?pwd=hXtbnj0t8rpSbybIkhGUYwEjZ1dgxN.1> [zoom.ico]<https://polimi-it.zoom.us/j/95837122103?pwd=hXtbnj0t8rpSbybIkhGUYwEjZ1dgxN.1> Link Seminario Polimi: <https://www.mate.polimi.it/Eventi/?id=2550&sezione_di_ricerca=&stringa=&sub…> Eventi Dipartimento di Matematica - Politecnico di Milano<https://www.mate.polimi.it/Eventi/?id=2550&sezione_di_ricerca=&stringa=&sub…> mate.polimi.it<https://www.mate.polimi.it/Eventi/?id=2550&sezione_di_ricerca=&stringa=&sub…> [apple-touch-icon.png]<https://www.mate.polimi.it/Eventi/?id=2550&sezione_di_ricerca=&stringa=&sub…> ----- Prof. Luca Scarpa, PhD Associate Professor in Probability Department of Mathematics Politecnico di Milano Via E. Bonardi 9 20133 Milano, Italy e.mail: luca.scarpa(a)polimi.it<mailto:luca.scarpa@polimi.it> url: https://sites.google.com/view/lucascarpa

1 0

Seminario Elena Montanaro - Politecnico di Milano - 13 Marzo 2025
by Luca Scarpa 04 Mar '25

04 Mar '25

Si segnala il seguente seminario a tutti gli interessati. Giovedì 13 Marzo 2025, ore 11:00. Aula Seminari VI Piano, Dipartimento di Matematica, Politecnico di Milano. Speaker: Elena Montanaro, Università La Sapienza. Title: An epidemic model using GW trees and coupon collectors. Abstract: We describe a model for information or viral transmission on the complete graph $\mathbb{K}_n$. Each node is an individual which may be susceptible, infected or recovered. This model has been introduced by Comets et al. with the main goal of studying the asymptotic behavior, as $n$ goes to infinity, of the duration of the infection and of the proportion of infected individuals in the population. The results rely on two interesting stochastic processes: the GW process and the coupon collector process. We discuss some extensions of this problem Link Zoom: <https://polimi-it.zoom.us/j/95837122103?pwd=hXtbnj0t8rpSbybIkhGUYwEjZ1dgxN.1> Join our Cloud HD Video Meeting<https://polimi-it.zoom.us/j/95837122103?pwd=hXtbnj0t8rpSbybIkhGUYwEjZ1dgxN.1> polimi-it.zoom.us<https://polimi-it.zoom.us/j/95837122103?pwd=hXtbnj0t8rpSbybIkhGUYwEjZ1dgxN.1> [zoom.ico]<https://polimi-it.zoom.us/j/95837122103?pwd=hXtbnj0t8rpSbybIkhGUYwEjZ1dgxN.1> Link Seminario Polimi: <https://www.mate.polimi.it/Eventi/?id=2549&sezione_di_ricerca=&stringa=&sub…> Eventi Dipartimento di Matematica - Politecnico di Milano<https://www.mate.polimi.it/Eventi/?id=2549&sezione_di_ricerca=&stringa=&sub…> mate.polimi.it<https://www.mate.polimi.it/Eventi/?id=2549&sezione_di_ricerca=&stringa=&sub…> [apple-touch-icon.png]<https://www.mate.polimi.it/Eventi/?id=2549&sezione_di_ricerca=&stringa=&sub…> ----- Prof. Luca Scarpa, PhD Associate Professor in Probability Department of Mathematics Politecnico di Milano Via E. Bonardi 9 20133 Milano, Italy e.mail: luca.scarpa(a)polimi.it<mailto:luca.scarpa@polimi.it> url: https://sites.google.com/view/lucascarpa

1 0

Seminario PRISMA lunedì 3 marzo 2025 - G. Cannizzaro & F. Toninelli
by Sonia Mazzucchi 03 Mar '25

03 Mar '25

Buongiorno, ricordiamo che *oggi lunedì 3 marzo dalle 16:30 alle 17:45* si terrà il seminario on-line del gruppo UMI - PRISMA ( http://www.umi-prisma.polito.it/). I seminari PRISMA hanno un formato di "colloquium" per creare un'occasione di scambio e discussione con tutta la comunità dei probabilisti e statistici italiani. Ogni giornata comprende due relatori che tengono due seminari di 30 minuti strettamente connessi, per presentare alla comunità una prospettiva sul proprio ambito di ricerca. Le registrazioni dei seminari vengono pubblicate sul canale YouTube dell'UMI: https://youtube.com/playlist?list=PLmySpc-jrtAMq84VH71evyqPc1hl6eEQb I relatori di oggi saranno *Giuseppe Cannizzaro* (University of Warwick) e *Fabio Toninelli* (Technical University of Vienna) che parleranno di: Teorema del Limite Centrale superdiffusivo per l'equazione di Burgers stocastica alla dimensione critica. con il seguente orario: 16:30 Primo seminario 17:00 Pausa e discussione 17:15 Secondo seminario 17:45 Conclusione e discussione Trovate di seguito il riassunto. I seminari verranno trasmessi via Zoom al seguente link: https://unipd.zoom.us/j/81175434050?pwd=hCozT8gqnlu49Io6LawZWAwLDrnaJ7.1 Meeting ID: 811 7543 4050 Passcode: 871716 Vi aspettiamo numerosi! Alberto Chiarini e Sonia Mazzucchi %%%%%%%%%%%%%%%%%%%%%%%%%%%% RELATORI: Giuseppe Cannizzaro (University of Warwick) e Fabio Toninelli (Technical University of Vienna) TITOLO: Teorema del Limite Centrale superdiffusivo per l'equazione di Burgers stocastica alla dimensione critica RIASSUNTO: L'equazione di Burgers Stocastica (EBS) è stata introdotta da van Beijren, Kutner and Spohn per modellizzare sistemi diffusivi asimmetrici con una singola quantità conservata (e.g. il modello di esclusione semplice asimmetrico). Nella dimensione sub-critica d=1, EBS coincide con la derivata dell'equazione KPZ il cui comportamento a grandi scale è superdiffusivo con crescita polinomiale e le cui fluttuazioni coincidono con il KPZ Fixed Point, mentre nelle dimensioni super-critiche d>2, è diffusivo e converge a un'equazione del calore stocastica anisotropica. Alla dimensione critica, è stato congetturato che la EBS sia superdiffusiva con crescita logaritmica con un esponente preciso ma ciò è stato mostrato solo modulo correzioni di ordine inferiore. Il presente seminario è basato su un lavoro assieme a Quentin Moulard https://arxiv.org/abs/2501.00344, in cui indentifichiamo la superdiffusività e deriviamo le asintotiche della matrice di diffusione in modo esatto. Inoltre, dimostriamo che nel limite di scala corretto, ovvero che tiene presente della crescita logaritmiche alla diffusività, la soluzione di EBS soddisfa un teorema del limite centrale. Il nostro è il primo limite di scala superdiffusivo per un'equazione alle derivate parziali stocastica critica, al di là dell'ambito di applicabilità della teoria delle strutture di regolarità di Hairer. %%%%%%%%%%%%%%%%%%%%%%%%%%%%

1 0

Seminario Padova - Marc Hoffman
by alekos.cecchin＠unipd.it 01 Mar '25

01 Mar '25

Buongiorno a tutti, Vorremmo segnalarvi che venerdì prossimo (7 Marzo) in aula 2BC30 (Torre Archimede, Università di Padova) ci sarà un seminario per il ciclo di seminari in Probabilità e Finanza di: Marc Hoffman (Université Paris-Dauphine) <https://www.ceremade.dauphine.fr/~hoffmann/> https://www.ceremade.dauphine.fr/~hoffmann/ Title: Some questions in mathematical statistics linked to evolution PDEs Date: March 7, 2025, at 14:30, room 2BC30 Abstract: Evolution models in applications are often analysed via PDEs, interpreted as a macroscopic decription of the phenomenon of interest. This classical approach is nevertheless challenged by empirical data for model validation, especially when the phenomenon of interest does not depend on well established physical laws. In particular the statistical inference of parameters (estimation and testing) requires a underlying stochastic model. This is usullay treated via some addition of noise, sometimes artificially and always a bit arbitrarily. Relying on some specific examples that appear in population biology (cell growth, human demography) or agent-based models in economy, we propose an alternative approach. Starting from a microscopic stochastic model that can be partially observed and for which the PDE of interest is a mean-field limit, the intrinsic statistical noise becomes the fluctuation between the empirical measure of the particle system and the solution of the PDE. We will outline a rigorous statistical program in this setting and will give some results on McKean-Vlasov models that shall emphasise the interest of our approach. Vi aspettiamo numerosi! Alberto Chiarini e Alekos Cecchin Sito web del seminario: https://www.math.unipd.it/~chiarini/seminars/

1 0

Ait-Sahalia seminar in Verona, 14/3/2025
by Cecilia Mancini 28 Feb '25

28 Feb '25

Professor Yacine Ait-Sahalia will give the seminar So Many Jumps, So Little News At the Department of Economics of the University of Verona, on Friday, March 14, 2025, at noon (12 pm) Via Cantarane 24, Vaona Room, 1st floor It will be possible also to attend on Zoom here https://univr.zoom.us/j/93150650381 All the interested people are warmly invited to attend Abstract This paper relates jumps in high frequency stock prices to firm-level, industry and macroeconomic news, in the form of machine-readable releases from Thomson Reuters News Analytics. We find that most relevant news, both idiosyncratic and systematic, lead quickly to price jumps, as market efficiency suggests they should. However, in the reverse direction, the vast majority of price jumps do not have identifiable public news that can explain them, in a departure from the ideal of a fair, orderly and efficient market. We show that jumps without news do not correlate with observable proxies for asymmetric or private information, and that microstructure-driven variables have only limited power to help predict the occurrence of jumps without news.

1 0

Jump to page:

2025

2024

2023

2022

2021

2020

2019

2018

2017

2016

2015

2014

2013

Random