November 2022 - Random - Mailing list — Dipartimento di Matematica, UniPI

Seminario Van Bever UPO - domani ore 16.00
by Enea Bongiorno 07 Nov '22

07 Nov '22

Cari colleghi, inoltro promemoria per il seguente seminario. Un cordiale saluto a tutti, Enea Bongiorno -------------------------------------- 8th of November, at 16.00: - in presence: room 201 of the campus Perrone, via Perrone, 18, Novara Università del Piemonte Orientale, Dipartimento di Studi per l’Economia e l’Impresa. - on-line at the link: meet.google.com/yvq-ccbt-pzt Prof. Germain Van Bever Université de Namur, Belgio Title: Flexible Hilbertian Additive Regression with Small Errors-in-Variables Abstract: In this talk, we present a new framework of additive regression modelling for data in very generic settings. More precisely, we tackle the problem of estimating component functions of additive models where the regressors and/or response variable belong to general Hilbert spaces and can be imperfectly observed. By this,we mean that some variables can be either measured incompletely or with errors. Smooth backﬁtting methods are used to estimate consistently the component functions and we provide explicit rates of convergence. We amply illustrate our methodology in various settings, including the functional, Riemannian and Hilbertian settings. -- Enea Bongiorno,PhD Associate Professor of Statistics Università degli Studi del Piemonte Orientale Via Perrone 18, 28100, Novara, Italia Phone: +390321375317 enea.bongiorno(a)uniupo.it upobook.uniupo.it/enea.bongiorno

1 0

Seminar in Statistics - MASSIMILIANO PONTIL
by Pierpaolo De Blasi 07 Nov '22

07 Nov '22

SEMINARS IN STATISTICS @ COLLEGIO CARLO ALBERTO <https://www.carloalberto.org/events/category/seminars/seminars-in-statistic…> Venerdi 11 Novembre 2022, alle ore 12.00, presso il Collegio Carlo Alberto, in Piazza Arbarello 8, Torino, si terrà il seguente seminario: ------------------------------------------------ Speaker: *Massimiliano Pontil* (Italian Institute of Technology and University College London) Title: *Learning Dynamical Systems via Koopman Operator Regression in Reproducing Kernel Hilbert Spaces* Abstract: In the last couple of years the Koopman operator framework attracted a lot of attention due to growing use of data-driven dynamical systems in science and engineering. Relevant results span fields of functional analysis, numerical algorithms, as well as machine learning. In this talk we will focus on discrete dynamical systems modelled by Markov chains and their study through the corresponding Koopman operator. While many data-driven algorithms to reconstruct such operators are well known, their relationship with statistical learning is largely unexplored. We will introduce a framework to learn the Koopman operator from a finite data sample of the dynamical system. We will limit to the important case when the Markov chain admits an invariant distribution and, relying on the theory of reproducing kernel Hilbert spaces (RKHS), introduce a notion of risk from which different estimators naturally arise. Special attention will be given to the estimation of the Koopman spectral properties, and in particular its modal decomposition (KMD) that is of paramount importance in practice. With this framework we will analyse, theoretically and empirically, some existing estimators, e.g. (extended) dynamic mode decomposition (DMD), and introduce a novel reduced-rank operator regression (RRR) estimator. We will further present learning bounds for the proposed estimator, holding for both data drawn i.i.d. from the invariant distribution and for non i.i.d. data gathered from the trajectories of the dynamical system, the latter in terms of mixing coefficients. (Joint work with V. Kostic, P. Novelli, A. Maurer, C. Ciliberto, L. Rosasco) ------------------------------------------------ Sarà possibile seguire il seminario anche in streaming: Join Zoom Meeting <https://us02web.zoom.us/j/83848292614?pwd=MzV0UnhBN1RScTN0aWMvZ3lZdkpwQT09> Meeting ID: 838 4829 2614 Passcode: 771221 Il seminario è organizzato dalla "de Castro" Statistics Initiative www.carloalberto.org/stats -- Pierpaolo De Blasi University of Torino & Collegio Carlo Alberto carloalberto.org/pdeblasi <https://sites.google.com/a/carloalberto.org/pdeblasi/>

1 0

Bruti Liberati Prize - call for applications (fwd)
by Tiziano Vargiolu 07 Nov '22

07 Nov '22

Bruti Liberati Prize CALL FOR APPLICATIONS Dear Tiziano Vargiolu We are happy to announce the Bruti Liberati Prize 2022. Theses defended in 2020 and 2021 can be submitted this time. Application deadline is January 31st, 2023, 12:00 (UTC +1). You find all the necessary information on the website https://www.bachelierfinance.org/nicola-bruti-liberati-prize?mc_cid=36910c7… With best regards, Denise Denise Künzli Administrative Director of BFS ***************************************** ETH Zurich Denise Künzli Department of Mathematics HG G 32.3 Rämistrasse 101 8092 Zurich Switzerland Tel +41 44 632 64 65 Fax +41 44 632 14 74 email denise.kuenzli(a)math.ethz.ch Copyright © 2022 Bachelier Finance Society, All rights reserved. You were subscribed to the newsletter from Bachelier Finance Society Our mailing address is: Bachelier Finance SocietyRaemistrasse 101 Zürich 8092 Switzerland Add us to your address book Want to change how you receive these emails? You can update your preferences or unsubscribe from this list. Email Marketing Powered by Mailchimp [open.php?u=702156a1168de89843425f38f&id=36910c77a9&e=70b34a9999]

1 0

Seminario Sapienza Martedì 8 Novembre
by Lorenzo Taggi 07 Nov '22

07 Nov '22

Cari colleghi, riporto l'annuncio del seminario di Matteo Quattropani presso il dipartimento di Matematica di Sapienza Università di Roma. Cordiali saluti, Lorenzo Taggi *Data e ora: *Martedì 8 Novembre, ore 14.15, Sala di Consiglio, Dipartimento di Matematica di Sapienza Università di Roma *Title: *Mixing of the Averaging process on graphs *Speaker:* Matteo Quattropani, Sapienza Università di Roma *Abstract:* The Averaging process (a.k.a. repeated averages) is a mass redistribution model over the vertex set of a graph. Given a graph G, the process starts with a non-negative mass associated to each vertex. The edges of G are equipped with Poissonian clocks: when an edge rings, the masses at the two extremes of the edge are equally redistributed on these two vertices. Clearly, as time grows to infinity the state of the system will converge (in some sense) to a flat configuration in which all the vertices have the same mass. The process has been introduced to the probabilistic community by Aldous and Lanoue [1] in 2012, and recently received some attention thanks to the work of Chatterjee, Diaconis, Sly and Zhang [2], where the authors show an abrupt convergence to equilibrium (measured in L^1 distance) in the case in which the underlying graph is complete (and of diverging size). In this talk, I will present some recent results obtained in collaboration with F. Sau (IST Austria) [3,4] and P. Caputo (Roma Tre) [4]. In [3] we show that if the underlying graph is “finite dimensional” (e.g., a finite box of Z^d), then the convergence to equilibrium is smooth (i.e., without cutoff) when measured in L^p with p \in [1,2]. On the other hand, in [4] we show that a cutoff phenomenon (for the L^1 and L^2 distance to equilibrium) takes place when the underlying graph is the hypercube or the complete bipartite graph. [1] David Aldous, and Daniel Lanoue. A lecture on the averaging process. Probab. Surv., 9:90–102, 2012. [2] Sourav Chatterjee, Persi Diaconis, Allan Sly, and Lingfu Zhang. A phase transition for repeated averages. Ann. Probab. 50(1):1–17, 2022. [3] Matteo Quattropani and Federico Sau. Mixing of the Averaging process and its discrete dual on finite-dimensional geometries. Ann. Appl. Probab. (to appear). [4] Pietro Caputo, Matteo Quattropani and Federico Sau. Cutoff for the Averaging process on the hypercube and complete bipartite graphs. (to appear).

1 1

SPASS seminars: Giulia Livieri & Robin Stephenson - TUE 08.11 at 14:00
by Andrea Agazzi 06 Nov '22

06 Nov '22

Dear Colleagues, We would like to invite you to the following SPASS <https://sites.google.com/unipi.it/spass> seminars, jointly organized by UniPi, SNS, UniFi and UniSi: - *N-player Games and Mean Field Games of Moderate Interaction* Giulia Livieri (Scuola Normale Superiore di Pisa) - *Scaling Limits of Multi-Type Markov Branching Trees* Robin Stephenson (University of Sheffield) The seminars will take place in person on *TUE, 08.11.2022 at 14:00* (the second talk starting at 15:00) in Sala Seminari, Dipartimento di Matematica, University of Pisa and streamed online here <https://meet.google.com/gji-phwo-vbg>. The organizers, A. Agazzi, G. Bet, A. Caraceni, F. Grotto, G. Zanco https://sites.google.com/unipi.it/spass -------------------------------------------- Abstracts: *N-player Games and Mean Field Games of Moderate Interaction* *We study the asymptotic organization among many optimizing individuals interacting in a suitable "moderate" way. We justify this limiting game by proving that its solution provides approximate Nash equilibria for large but finite player games. This proof depends upon the derivation of a law of large numbers for the empirical processes in the limit as the number of players tends to infinity. Because it is of independent interest, we prove this result in full detail. We characterize the solutions of the limiting game via a verification argument.* *Scaling Limits of Multi-Type Markov Branching Trees* *Consider a population where individuals have two characteristics: a size, which is a positive integer, and a type, which is a member of a finite set. This population reproduces in a Galton-Watson fashion, with one additional condition: given that an individual has size n, the sum of the sizes of its children is less than or equal to n. We call multi-type Markov branching tree the family tree of such a population.*

1 0

Seminars: Mirko D'Ovidio and Mario Maurelli at Trento 8-9/11/2022
by Luigi Amedeo Bianchi 04 Nov '22

04 Nov '22

Dear all, we announce two seminars being held next week in Trento, as well as online on Zoom in the Trento Probability Seminar. On Tuesday, November 8th at 2.30 pm (CET) in "Aula 7" - PovoZero Mirko D'Ovidio (Università di Roma Sapienza) On the non-local boundary value problem from the probabilistic viewpoint On Wednesday, November 9th at 2.30 pm (CET) in "Aula B110" - Povo2 Mario Maurelli (Università di Pisa) A McKean-Vlasov SDE and particle system with interaction from reflecting boundaries The posters of the two talks (with the abstracts and the Zoom links and passwords), as well as a schedule of the upcoming events of the Trento Probability Seminar can be found in the following page: https://sites.google.com/unitn.it/unitn-ps/home The organisers Luigi Amedeo Bianchi, Stefano Bonaccorsi, Michele Coghi

1 0

Postdoc positions at Milano-Bicocca
by Maurizia Rossi 04 Nov '22

04 Nov '22

Dear all, There are some postdoctoral positions available at the University of Milano-Bicocca for candidates in all areas of Mathematics (deadline: November 24, 2022). https://www.unimib.it/ateneo/gare-e-concorsi/assegni-ricerca-tipo-a2-a2-typ… In particular, I encourage candidates working in Probability Theory, Mathematical Statistics and related fields to submit their application. Please, do not hesitate to contact me or bandi.assegni_borse(a)unimib.it if you have any questions. Best wishes, Maurizia Rossi -- Maurizia Rossi Dipartimento di Matematica e Applicazioni Università degli Studi di Milano-Bicocca https://mauriziarossi.wordpress.com

1 0

Assegno di Ricerca SNS
by Marta Leocata 03 Nov '22

03 Nov '22

Cari tutti, è stato aperto un assegno di ricerca di 12 mesi presso la Scuola Normale Superiore di Pisa. Il tema dell'assegno è "Modelli Matematici per la transizione energetica" e la scadenza è il 23 Novembre 2022 alle ore 16:00. Tutte le informazioni ed il bando sono reperibili al sito: https://amministrazionetrasparente.sns.it/scuola/opportunità-offerte-dalla-… <https://amministrazionetrasparente.sns.it/scuola/opportunit%C3%A0-offerte-d…> Cordiali Saluti Marta Leocata

1 0

[PRISMA] seminari di Paolo Dai Pra e Alberto Chiarini
by Domenico Marinucci 03 Nov '22

03 Nov '22

Cari colleghi i seminari del gruppo UMI Prisma riprenderanno a partire da Novembre con il calendario consueto (primo lunedì del mese, ore 16-18, online su piattaforma Teams). Qui sotto i dettagli del prossimo incontro (Paolo Dai Pra e Alberto Chiarini), grazie per l'attenzione, Domenico Marinucci * November 7, 2022, 16:00-17:00 (CET): Paolo Dai Pra TITLE: Noise-induced periodicity in stochastic dynamics: some examples ABSTRACT: The emergence of periodic behavior in the dynamics of several interacting components is a common pattern of self-organisation in living systems. Rigorous mathematical treatments are still limited to few examples. In this talk we review some of these examples, emphasizing the essential role of the noise in the appearance of regular rhythms. * November 7, 2022, 17:00-18:00 (CET): Alberto Chiarini TITLE: How costly is it for a simple random walk to cover a fraction of amacroscopic body? ABSTRACT: In this talk we aim at establishing large deviation estimates for the probability that a simple random walk on the Euclidean lattice (d>2) covers a substantial fraction of a macroscopic body. It turns out that, when such rare event happens, the random walk is locally well approximated by random interlacements with a specific intensity, which can be used as a pivotal tool to obtain precise exponential rates. Random interlacements have been introduced by Sznitman in 2007 in order to describe the local picture left by the trace of a random walk on a large discrete torus when it runs up to times proportional to the volume of the torus, and has been since a popular object of study. In the first part of the talk we introduce random interlacements and give a brief account of some results surrounding this object. In the second part of the talk we study the event that random interlacements cover a substantial fraction of a macroscopic body. This allows to obtain an upper bound on the probability of the corresponding event for the random walk. Finally, by constructing a near-optimal strategy for the random walk to cover a macroscopic body, we discuss a matching large deviation lower bound. The talk is based on ongoing work with M. Nitzschner (NYU Courant). Link dei seminari: https://teams.microsoft.com/l/meetup-join/19%3a667d2414be564c5d8fba30acffeb… -- @@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@ Domenico Marinucci Dipartimento di Matematica Università di Roma Tor Vergata https://www.mat.uniroma2.it/~marinucc/ @@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@

1 0

Fwd: position at IST Lisbon
by Faggionato, Alessandra 03 Nov '22

03 Nov '22

Buongiorno, ricevo e con piacere inoltro. Saluti Alessandra ---------- Forwarded message --------- From: Patricia Gonçalves <pgoncalves(a)tecnico.ulisboa.pt> Date: Wed, 2 Nov 2022 at 23:47 Subject: position at IST Lisbon To: PATRICIA <pgoncalves(a)tecnico.ulisboa.pt> Dear colleagues I am writing to you because a position in *Probability and Statistics* just opened in my department. Here is the announcement: https://drh.tecnico.ulisboa.pt/assistant-professor-dm-probability-and-stati… Please forward this email to those that you think that might be interested. The position is for assistant professor, but the candidate can be promoted to associate or even full professor in a short time depending on the CV. The teaching at IST runs in 4 quarters per year and it is possible to accumulate all the teaching in two quarters. Typically we have to teach 6h /week and an average of 2/3 courses per year. IST is a great place to work and our students are very strong. Lisbon is a very nice city. If you need any additional information please contact me. Many thanks. Patricia Patrícia Gonçalves Mathematics Department Instituto Superior Técnico University of Lisbon Portugal -- ************************************************* Prof. Alessandra Faggionato https://www1.mat.uniroma1.it/people/faggionato/ Department of Mathematics University "La Sapienza" Piazzale Aldo Moro, 5 00185 - Rome Office 5, Phone (0039) 06 49913252 *************************************************

1 0