- Random - Mailing list — Dipartimento di Matematica, UniPI

Seminars in Statistics at Collegio Carlo Alberto - Fadoua BALABDAOUI (ETH ZURICH)
by Matteo Giordano 31 Oct '25

31 Oct '25

SEMINARS IN STATISTICS @ COLLEGIO CARLO ALBERTO <https://www.google.com/url?q=https://www.carloalberto.org/events/category/s…> Venerdì 07/11/2025, presso il Collegio Carlo Alberto, in Piazza Arbarello 8, Torino, si terrà il seguente seminario: ------------------------------------------------ 12.00-13.00 Speaker: Fadoua BALABDAOUI (ETH ZURICH) Title: Unmatched linear regression: Asymptotic results under identifiability Abstract: Consider the regression problem where the response $Y\in \mathbb R$ and the covariate $X\in \mathbb R^d $ for $d\geq 1$ are unmatched. Under this scenario we do not have access to pairs of observations from the distribution of $(X, Y)$, but instead we have separate data sets $\{Y_i\}_{i=1}^n$ and $\{X_j\}_{j=1}^m$, possibly collected from different sources. We study this problem assuming that the regression function is linear and the noise distribution is known or can be estimated. We introduce an estimator of the regression vector based on deconvolution (the DLSE) and demonstrate its consistency and asymptotic normality under an identifiability assumption. Under non-identifiability of the regression vector but identifiability of the distribution of the predictor, we construct an estimator of the latter based on the DLSE and show that it converges to the true distribution of the predictor at the parametric rate in the Wasserstein distance of order 1. We illustrate the theory with several simulation results. ------------------------------------------------ Sarà possibile seguire il seminario anche in streaming: chiunque volesse collegarsi è pregato di inviare una email entro *mercoledì 05/11/2025* a matteo.giordano(a)unito.it <mailto:matteo.giordano@unito.it> Il webinar è organizzato dalla "de Castro" Statistics Initiative (www.carloalberto.org/stats <http://www.carloalberto.org/stats>) in collaborazione con il Collegio Carlo Alberto. Cordiali saluti, Matteo Giordano Assistant Professor (RTDA) Department of Economics, Social Studies, Applied Mathematics and Statistics (ESOMAS) www.matteogiordano.weebly.com <https://matteogiordano.weebly.com/>

1 0

Maria Kalli and Jim Griffin Seminars at Ca' Foscari University of Venice - 3 November 2025
by Roberto CASARIN 31 Oct '25

31 Oct '25

Dear Colleagues, I'm pleased to invite you to the Department Seminars, which will be held on Monday, November 3 at 11:00 in Meeting Room 1 with the following schedule: - 11:00-12:00: *Maria Kalli *(*King's College London*), Network Modeling of Asynchronous Change-Points in Multivariate Time Series - 12.15- 13.15: *Jim Griffin* (*University College London*), Some approaches to modelling high-dimensional multivariate time series All the interested researchers are warmly invited to attend in person or online! Best regards Roberto Casarin (and on behalf of the Organizing Committee) More information and Zoom link are available here: https://www.unive.it/data/agenda/1/104528 https://unive.zoom.us/j/81247640154?pwd=rPM81OcUZRb5VIW4NSHwOPLurD01le.1 *Title*: Network Modeling of Asynchronous Change-Points in Multivariate Time Series *Abstract *: We introduce a novel Bayesian method for asynchronous change-point detection in multivariate time series. This method allows for change-points to occur earlier in some (leading) series followed, after a short delay, by change-points in some other (lagging) series. Such dynamic dependence structure is common in fields such as seismology and neurology where a latent event such as an earthquake or seizure causes certain sensors to register change-points before others. We model these lead-lag dependencies via a latent directed graph and provide a hierarchical prior for learning the graph’s structure and parameters. Posterior inference is made tractable by modifying particle MCMC methods designed for univariate change-point problems. We apply our method to both simulated and real datasets from the fields of seismology and neurology. In the simulated data, we find that our method outperforms competing methods in settings where the change-point locations are dependent across series. In the real data applications we show that our model can also uncover an interpretable network structure. *Title*: Some approaches to modelling high-dimensional multivariate time series *Abstract*: There has been an increasing interest in modelling high-dimensional multivariate economic time series. Many models build on the work-horse Vector AutoRegression (VAR) and its time-varying extension to TVP-VAR. These models can provide better forecasts and structural analysis than low-dimensional models (particularly during crisis periods) but the large number of parameters can be challenging both inferentially and computationally. In this talk, I will review two recent approaches. The first is the Tensor VAR (TVAR) model which uses a tensor structure to achieve dimension reduction in the coefficient matrices of the VAR. I will discuss Bayesian inference in these models and an extension to a time-varying parameter model. The second approach considers the time-varying Factor Augmented VAR (FA-VAR) and uses an autoencoder to extract low-dimensional non-linear factors from high-dimensional data. I will discuss how a shrinkage prior using groupings of the variables can lead to identifiable factors and better predictive performance. -- Roberto Casarin, PhD Professor of Econometrics Ca' Foscari University of Venice San Giobbe 873/b - 30121 Venezia, Italy http://sites.google.com/view/robertocasarin/ https://www.unive.it/vera <https://www.unive.it/isba2024> https://www.unive.it/isba2024

1 0

OWPS today
by Federico Sau 30 Oct '25

30 Oct '25

Dear all, This is a reminder for today's seminar by Barbara Dembin (Strasbourg) and Ron Peled (Maryland) on Minimal surfaces in random environment, at 14:00 Rome time (please, note the exceptional time). All info's here: https://www.owprobability.org/one-world-probability-seminar. Looking forward to seeing many of you! Best, the organizers *** Il tuo 5x1000 al diritto allo studio Università degli Studi di Milano CF 80012650158

1 0

Several Assistant/Associate/Full Professor positions at Imperial
by Passeggeri, Riccardo 29 Oct '25

29 Oct '25

Salve a tutti, Vorrei segnalarvi che il Dipartimento di Matematica dell’Imperial College London ha aperto diverse posizioni a tutti i livelli: Assistant, Associate e Full Professor. Da notare che la posizione di Assistant Professor è permanente (è una tenured position). Le posizioni riguardano tutte e quattro le sezioni del Dipartimento: Statistics, Mathematical Finance, Pure Mathematics e Applied Mathematics & Mathematical Physics. Inoltre, sono disponibili diverse posizioni (several positions), poiché il College intende espandere significativamente il Dipartimento nei prossimi anni. Potete trovare tutte le informazioni al seguente link: https://www.imperial.ac.uk/jobs/search-jobs/description/index.php?jobId=259… Cordiali saluti, Riccardo

1 0

Seminario Kais Ammari - Politecnico di Milano - 3 Novembre 2025
by Luca Scarpa 29 Oct '25

29 Oct '25

Si segnala il seguente seminario a tutti gli interessati. Lunedì 3 Novembre 2025, ore 14:30. Aula Seminari VI Piano, Dipartimento di Matematica, Politecnico di Milano. Speaker: Kais Ammari, University of Monastir. Title: Degenerate Damping in Interacting Elastic Systems. Abstract: We study the regularity and stability of coupled elastic systems subject to distinct damping mechanisms: one acting through the average velocity and another via a fractional power of the elastic operator. The damping matrix is degenerate, meaning that dissipation does not affect all components equally. Using a frequency-domain approach based on resolvent estimates, we describe how this degeneracy influences the semigroup regularity and the decay of solutions. The obtained results are shown to be optimal and relevant for applications in structural mechanics and vibration control. Link Zoom: https://polimi-it.zoom.us/j/94510717258 Link Seminario Polimi: https://www.mate.polimi.it/Eventi/?id=2645&sezione_di_ricerca=probstat&stri… ----- 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 1

Nov 6 - Stats seminars Kopp @ Sapienza MEMOTEF
by Francesca Panero 29 Oct '25

29 Oct '25

Carissimi tutti, On Thursday 6th of November at the MEMOTEF Department, Sapienza University, we will have the pleasure to listen to the seminar of Emma Kopp<https://emmakopp1.github.io>, PhD student from CERMADE Paris-Dauphine University, with title Recent work on phylogenetics applied to historical linguistic and cultural evolution. The seminar will take place 9-10am in Aula Cristina Di Fresco (4th floor of the Economics building, administration corridor, Via del Castro Laurenziano 9 Roma). You can find the abstract below. Best wishes, Francesca Recent work on phylogenetics applied to historical linguistic and cultural evolution Linguistic phylogenies reconstruct the evolutionary relationships between languages based on cognate data (presence/absence of shared linguistic traits). We use theoretical bounds derived from Mossel's work to determine the temporal limit to which phylogenetic methods can reliably reconstruct linguistic tree topology or ancestral states. The study combines simulation of synthetic data on trees to assess reconstruction accuracy as a function of tree age and number of cognates, and ancestral state reconstruction on real lexical data from Sino-Tibetan and Bantu language families. The study methodologically demonstrates that for languages evolving at rates typically observed in the literature, it is impossible to reconstruct the topology of a tree whose root age exceeds 12,000 years. Beyond this threshold, the inferred topology will be no more reliable than a random estimate. Analysis shows that increasing the number of traits improves reconstruction for ancient trees, but gains remain limited. Ancestral state reconstruction results show that certain semantic categories (body parts, numerical concepts and natural elements) can be reconstructed at remarkable temporal depths. This convergence in the retention of essential concepts suggests the existence of universal constraints in lexical evolution. These results establish for the first time a theoretical quantitative bound on phylolinguistic methods, demonstrating that reconstruction of deep topologies of ancient linguistic families based on cognate lexical data constitutes a doomed enterprise. ------------------------------------------- Dr Francesca Panero (she/her) Assistant Professor in Statistics (RTT), Department of Methods and Models for Economics, Territory and Finance Sapienza University, Rome Visiting Fellow, Department of Statistics London School of Economics and Political Science Visiting Lecturer, Faculty of Informatics Università della Svizzera Italiana Website: https://francescapanero.github.io

1 0

Seminars of Tiozzo, Klippel, Jara and D'Alimonte at La Sapienza
by Faggionato, Alessandra 29 Oct '25

29 Oct '25

Dear all, In addition to the already announced seminar by Tiozzo today (*Harmonic functions on groups, random walks, and the identification of the Poisson boundary*), we will have three seminars in Probability at the Department of Mathematics of Sapienza University in the coming weeks. The speakers will be Andreas Klippel (TU Darmstadt), Milton Jara (IMPA, Rio de Janeiro), and Lucas D’Alimonte (LPSM – Sorbonne Université). Below you can find the titles and abstracts. Buona giornata Alessandra ************************************************** *Monday, November 3 2025* *16:15, Sala di Consiglio, Dipartimento di Matematica* *Speaker: *Andreas Klippel (TU Darmstadt) *Title*: Two Sides of One Coin: Approaches to the Random Loop Model *Abstract: *In the last decades, graphical representations have emerged as powerful tools to study models from statistical physics. One prominent example is the random loop model, whose two-point function encodes various spin correlations of quantum systems such as the Heisenberg ferromagnet, the antiferromagnet, and the quantum XY model. Since the model lacks monotonicity properties and correlation inequalities such as FKG, alternative techniques have been developed to analyze it. We will discuss two complementary approaches suitable for different regimes. The first concerns the absence of long loops, corresponding to the regime without a phase transition. This situation can be studied by comparing the model to a percolation process and showing that certain structural features effectively reduce the percolation parameter, leading to exponentially small loops. The second approach addresses the occurrence of a phase transition, which is typically established through the method of reflection positivity. The presentation will provide an introduction to the random loop model, outline these two analytical techniques, and present several results illustrating their application. ********************************************************************* *Monday, November 10 2025* *16:15, Sala di Consiglio, Dipartimento di Matematica* *Speaker: *Milton Jara (Impa, Rio de Janeiro) *Title*: Quantitative Hydrodynamics for a generalized contact model *Abstract: *We use the formalism of Quantitative Hydrodynamics to improve the quantitative hydrodynamic limit obtained in Chariker, De Masi, Lebowitz and Presutti (2023) for an interacting particle system inspired by integrate-and-fire neuron models. Our estimates are good enough to show that the typical fluctuations around the aforementioned hydrodynamic limit are Gaussian, and governed by an inhomogeneous stochastic linear equation. Joint work with Julian Amorim (IMPA) and Yangrui Xiang (Louisiana State University) *********************************************************************** *Monday, November 17 2025* *16:15, Sala di Consiglio, Dipartimento di Matematica* *Speaker: *Lucas D’Alimonte (LPSM - Sorbonne Université) *Title:* Ornstein—Zernike theory for the near-critical planar random cluster model *Abstract:* In this talk, we will discuss the classical Ornstein-Zernike theory for the random-cluster model (also known as FK percolation). In its modern form, it is a very robust theory, which most celebrated output is the computation of the asymptotically polynomial corrections to the pure exponential decay of the two-points correlation function of the random-cluster model in the subcritical regime. We will present an ongoing project that extends this theory to the near-critical regime of the two-dimensional random-cluster model, thus providing a precise understanding of the Ornstein-Zernike asymptotics when p approaches the critical parameter p_c. The output of this work is a formula encompassing both the critical behaviour of the system when looked at a scale negligible with respect to its correlation length, and its subcritical behaviour when looked at a scale way larger than its correlation length. Based on a joint work with Ioan Manolescu. -- ************************************************* Prof. Alessandra Faggionato https://www1.mat.uniroma1.it/people/faggionato/ Department of Mathematics University "La Sapienza" Piazzale Aldo Moro, 5 00185 - Rome Office 123, first floor *************************************************

1 0

A spooky week in Tor Vergata
by Michele Salvi 28 Oct '25

28 Oct '25

Dear all, Next week RoMaDS <https://www.mat.uniroma2.it/~rds/events.php> will host a spooky lineup of seminars at the Mathematics Department of Tor Vergata University. Here is the program (for the abstract, see below): 03.11 Giorgio Cipolloni (Tor Vergata) "Logarithmically correlated fields from large random matrices" 14h00 in Aula Dal Passo 05.11 Milton Jara (IMPA, Rio de Janeiro) "NESS for KPZ" 16h00 in Aula D'Antoni 07.11 Maurice Duits (KTH Royal Institute of Technology, Stockholm) "Integrable Structures Behind the Aztec Diamond" 14h00 in Aula D'Antoni We encourage in-person participation. Should you be unable to come, here is the link to the Teams streaming of all of the seminars: Spooky seminars | Meeting-Join | Microsoft Teams <https://teams.microsoft.com/meet/3740857632924?p=3G7X9MF2NwcSKIQczz> Best, Michele Abstracts Giorgio Cipolloni (Tor Vergata) "Logarithmically correlated fields from large random matrices” We study the Brownian evolution of large non-Hermitian matrices and show that their log-determinant converges to a 2+1 dimensional Gaussian field in the Edwards-Wilkinson regularity class, i.e. logarithmically correlated for the parabolic distance. This gives a dynamical extension of the celebrated result by Rider and Virag (2006) proving that the fluctuations of the eigenvalues of Gaussian non-Hermitian matrices converge to the Gaussian Free Field. Milton Jara (IMPA, Rio de Janeiro) "NESS for KPZ" We show that the fluctuations of the density of boundary driven, weakly asymmetric systems are described by energy solutions of the KPZ equation with corresponding boundary conditions. Conditioned on the uniqueness of these energy solutions, we show that the non-equilibrium stationary states (NESS) of these systems are described by the invariant measures of KPZ introduced by Barraquand, Bryc, Corwin, Knizel among others. Joint work with Juan Arroyave (IMPA). Maurice Duits (KTH Royal Institute of Technology, Stockholm) "Integrable Structures Behind the Aztec Diamond" The Aztec diamond, under the uniform measure on domino tilings, is one of the classic examples of an exactly solvable model in probability and statistical mechanics. Its rich geometric features—such as limit shapes and arctic boundaries—have long made it a cornerstone of integrable probability. More recently, variants of this model with doubly periodic weights have revealed that much of the underlying structure persists far beyond the uniform case and can be used to uncover new behaviors—such as regions with smooth disorder—that were previously out of reach. At the heart of these models lies a birational map that encodes their integrable character. In this talk, I will describe how this map unifies different regimes of the Aztec diamond—from uniform and periodic settings to models in random environments. I will also discuss how integrable features survive (sometimes unexpectedly) in the presence of disorder, and how they connect to other probabilistic models such as directed polymers. The presentation is aimed at a broad mathematical audience, and no prior background in tilings or integrable systems will be assumed.

1 0

Seminario di Kei Kobayashi
by Enrica Pirozzi 28 Oct '25

28 Oct '25

Carissimi di seguito trovate l'avviso del seminario: -- AVVISO DI SEMINARIO   Giovedì 30 ottobre, alle ore 12:30, in aula G del Dipartimento di Matematica e Fisica dell'Università della Campania Luigi Vamvitelli, in Viale Lincoln 5, Caserta, Kei Kobayashi Professor of Mathematics, Department of Mathematics, Fordham University, New York, USA, terrà un seminario dal titolo Parameter estimation for one-sided heavy-tailed distributions Abstract: Stable subordinators have been widely used in the context of subdiffusions, where particles get trapped or immobile in a number of time periods, called constant periods. The lengths of the constant periods follow a one-sided stable distribution whose first moment does not exist. In this talk, we construct an estimator for the stability index, applying the method of moments to the number of observed constant periods in a fixed time interval. The resulting estimator is asymptotically unbiased and consistent, and it is well-suited for situations where multiple observations of the same subdiffusion process are available. We present supporting numerical examples and an application to market price data for a low-volume stock. This is joint work with Phillip Kerger. -- Questo è il link da remoto: Seminario di Kei Kobayashi | Partecipazione alla riunione | Microsoft Teams<https://teams.microsoft.com/meet/3305423649328?p=buYuVJgBIf5KihIoRS> Cari saluti Enrica Pirozzi

1 0

Seminario di Giulio Tiozzo alla Sapienza il 29 Ottobre
by Faggionato, Alessandra 27 Oct '25

27 Oct '25

Buongiorno, vi segnalo il seminario di Giulio Tiozzo organizzato dal gruppo di Algebra e Geometria per questo Mercoledi' (sotto i dettagli) Saluti Alessandra %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% *Mercoledì 29 ottobre 2025* Ore 14:00, Sala di Consiglio, Dipartimento di Matematica, Sapienza Università di Roma Seminario di Algebra e Geometria Giulio Tiozzo (Sapienza Università di Roma) *Harmonic functions on groups, random walks, and the identification of the Poisson boundary* The Poisson boundary is a measure-theoretic object attached to a group equipped with a probability measure, and is closely related to the notion of harmonic function on the group. In many cases, the group is also endowed with a topological boundary arising from its geometric structure, and a recurring research theme is to identify the Poisson boundary with the topological boundary. For instance, for lattices in hyperbolic space, it is natural to ask if the (visual, or Gromov-)boundary of the hyperbolic space is a model for the Poisson boundary. In this talk, we solve the identification problem for the Poisson boundary of a random walk with finite entropy on a hyperbolic group and on a discrete subgroup of a semisimple Lie group. The main technical novelty is that we do not require any moment assumption on the measure. Joint with K. Chawla, B. Forghani, and J. Frisch. -- ************************************************* Prof. Alessandra Faggionato https://www1.mat.uniroma1.it/people/faggionato/ Department of Mathematics University "La Sapienza" Piazzale Aldo Moro, 5 00185 - Rome Office 123, first floor *************************************************

1 0