October 2023 - Random - Mailing list — Dipartimento di Matematica, UniPI

SPASS Seminar: Simon Michaël Schulz
by Francesco Grotto 20 Oct '23

20 Oct '23

Dear Colleagues, We would like to invite you to the following SPASS seminar, jointly organized by UniPi, SNS, UniFi and UniSi (abstract below): *Well-posedness and stationary states for a crowded active Brownian system with size-exclusion* by *Simon Michaël Schulz* (Scuola Normale Superiore) The seminar will take place on *TUE, 24.10.2023* at *14:00 CET *in Aula Seminari, Dipartimento di Matematica, University of Pisa and streamed online at the link below. The organizers, A. Agazzi, G. Bet, A. Caraceni, F. Grotto, G. Zanco https://sites.google.com/unipi.it/spass <https://www.google.com/url?q=https://sites.google.com/unipi.it/spass&source…> ------------------------------------------- Abstract: We prove the existence of solutions to a non-linear, non-local, degenerate equation which was previously derived as the formal hydrodynamic limit of an active Brownian particle system, where the particles are endowed with a position and an orientation. This equation incorporates diffusion in both the spatial and angular coordinates, as well as a non-linear non-local drift term, which depends on the angle-independent density. The spatial diffusion is non-linear degenerate and also comprises diffusion of the angle-independent density, which one may interpret as cross-diffusion with infinitely many species. Our proof relies on interpreting the equation as the perturbation of a gradient flow in a Wasserstein-type space. It generalizes the boundedness-by-entropy method to this setting and makes use of a gain of integrability due to the angular diffusion. We also prove uniqueness in the particular case where the non-local drift term is null, and provide existence and uniqueness results for stationary equilibrium solutions. This is joint work with Martin Burger.

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Manifestazione di interesse - assegni di rricerca presso Università Bocconi
by Antonio Lijoi 19 Oct '23

19 Oct '23

Gentili colleghe/i, inoltro un invito a manifestare interesse per posizioni da assegnista di ricerca che verranno bandite a breve dall’Università Bocconi. Cordiali saluti, Antonio Lijoi ------------ ** Call for expression of interest ** The Bocconi Institute for Data Science and Analytics (BIDSA) will soon open two post-doctoral positions on Bayesian Nonparametrics, under the supervision of Antonio Lijoi and Igor Pruenster. The start date should ideally be in early 2024 but there is some space for flexibility. Successful applicants will be based at the BayesLab (https://bayeslab.unibocconi.eu) a BIDSA research unit focusing on Bayesian learning. Potentially interested candidates are strongly encouraged to contact Antonio Lijoi (antonio.lijoi(a)unibocconi.it) or Igor Pruenster (igor(a)unibocconi.it) for further details, possibly before November 1, 2023.

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Seminars at Sapienza Univ. - 23-24 Oct.
by Luisa Beghin 19 Oct '23

19 Oct '23

Dear all, we are pleased to invite you to the two seminars organised by the Department of Statistical Sciences, Sapienza University of Rome, which can be followed via Zoom. *Location:* Room n.24, 4th floor, Edificio CU002 (Scienze Statistiche) *Zoom: * https://uniroma1.zoom.us/j/84380852385?pwd=RDBrcVdvelRMM0VmczlXYWgwL2pPZz09 *Time:* *Monday 23th of October, at 10.30* *Speaker: *Josè Luis Da Silva (University of Madeira - Portugal) *Title:* A Biorthogonal Approach to Infinite Dimensional Fractional Poisson Measures *Abstract*: We use a biorthogonal approach to the analysis of the infinite dimensional fractional Poisson measure. The complex Hilbert space w.r.t. these measures are described in terms of a proper system of generalized Appell polynomials. The kernels of the monomials may be expressed in terms of the Stirling operators of the first and second kind as well as the falling factorials in infinite dimensions. Associated to this system of Appell polynomials is the dual Appell system which is suitable to describe generalised functions. We then construct and characterize test and generalised functions in terms of integral transform as entire functions. *Time:* *Tuesday 24th of October, at 14.30* *Speaker: *Tobias Kuna (University of L'Aquila) *Title:* An Intrinsic Characterization of Moment Functionals in the Compact Case *Abstract:* We discuss characterizations of linear functionals $L$ on an unital commutative real algebra $A$ which can be represented as integral w.r.t. a compactly supported Radon measure on the character space of $A$. We give a characterization by the following three types of conditions: bounds on the growth of $(L(a^n))_n$, non-negativity of $L$ on Archimedean quadratic models, and continuity of $L$ w.r.t. submultiplicative seminorms on $A$. We will relate each of these conditions to a different technique solving this instance of the moment problem. Surprisingly, we can also provide an exact characterization of the compact support of the representing Radon measure purely in terms of $L$. This is a joint work arXiv:2204.05630 with Maria Infusino, Salma Kuhlmann and Patrick Michalski. Best regards. Luisa Beghin *************************************************************** Luisa Beghin Dipartimento di Scienze Statistiche Fac. Ingegneria dell'Informazione, Informatica e Statistica "SAPIENZA" Università di Roma Piazzale Aldo Moro 5, 00185 Roma T (+39) 06 49910543 F (+39) 06 4959241 https://sites.google.com/site/luisabeghin/ ***************************************************************** -- **Fai crescere le giovani ricercatrici e i giovani ricercatori* **con il 5 per mille alla Sapienza *Scrivi il codice fiscale dell'Università *80209930587 Cinque per mille <https://www.uniroma1.it/it/node/23149>*

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YStatS Webinar - Stochastic Fluid Dynamics
by Lucio Galeati 18 Oct '23

18 Oct '23

Dear all, It is my pleasure to announce an upcoming Webinar on Stochastic Fluid Dynamics, organized by the YoungStatS initiative, to take place on 15th November 2023 at 15:00 CET. There will be four young researchers speaking (Diego Alonso-Orán, Daniel Goodair, Erwin Luesink, Milo Viviani), moderated by Umberto Pappalettera. All further information, and the link to register to attend (registration is free but mandatory), can be found here: https://youngstats.github.io/post/2023/10/14/stochastic-fluid-dynamics/ Hope to see you there! Best, Lucio

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Annuncio "AN AUTUMN DAY IN PROBABILITY AND STATISTICAL PHYSICS"- 20 novembre 2023
by Luisa Andreis 17 Oct '23

17 Oct '23

Care colleghe e colleghi, Vi annunciamo che Lunedì 20 Novembre si terrà la dodicesima giornata di seminari: AN AUTUMN DAY IN PROBABILITY AND STATISTICAL PHYSICS University of Florence Monday 20 November 2023 Lecturers: Christina Goldschmidt (Oxford) and Rajat Subhra Hazra (Leiden) Location: Sala Tricerri, Dipartimento di Matematica e Informatica Ulisse Dini, viale Morgagni 67/a, Firenze, Firenze Ricordiamo che ciascun oratore farà una lezione introduttiva e divulgativa di 45 minuti pensata proprio per i non esperti, seguita da altri 45 minuti di tipo seminario (vedi programma). Maggiori informazioni, inclusi gli abstract dei talk, sono reperibili alla pagina web dell’evento<https://sites.google.com/unifi.it/florence-probability-group/home/days-in-p…>. Note pratiche: a coloro che fossero interessati (per una migliore organizzazione) chiediamo di compilare il seguente Google Form per indicare l'intenzione di partecipare alla giornata e in particolare al pranzo: https://docs.google.com/forms/d/e/1FAIpQLSdd9c4Oud-o_taW4ygl767bKWm1YhM9-x5… Vi aspettiamo numerosi e vi preghiamo di diffondere l’annuncio con chi pensiate possa essere interessato/a, in particolare giovani ricercatrici e ricercatori! Gianmarco Bet e Luisa Andreis Scientific advisory committee: F. Caravenna, E.N.M. Cirillo, F. Colomo, P. Dai Pra, A. De Masi, C. Giardina`, R. Livi, F. Martinelli, I.G. Minelli, B. Scoppola, E. Scoppola. PROGRAMMA Prof. Christina Goldschmidt (University of Oxford) Title: Trees and snakes Prof. Rajat Suburra Hazra (University of Leiden) Title: The membrane model 10:30-11:00 Welcome coffee 11.00-11.45 Introductory lecture: Goldschmidt 11.45-12.15 Break 12.15-13.00 Seminar: Goldschmidt 13.00-14.30 Lunch 14.30-15.15 Introductory lecture: Hazra 15.15-15.45 Break 15.45-16.30 Seminar: Hazra Trovate qui<https://drive.google.com/file/d/1GHmrRKm53NBGzkF0AHdQtbE8dlMnI4k6/view> il poster dell’evento. ------------------------------------------------------- Luisa Andreis ------------------------------------------------------- RTD-B Dipartimento di Matematica Politecnico di Milano Personal webpage: https://sites.google.com/view/luisaandreis/home Email: luisa.andreis(a)polimi.it<mailto:luisa.andreis@polimi.it>

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31st World Meeting of the International Society for Bayesian Analysis, ISBA2024
by Roberto CASARIN 17 Oct '23

17 Oct '23

Dear all, we are happy to announce the: *31st World Meeting of the International Society for Bayesian Analysis (ISBA)* *July 1-7, 2024, Ca' Foscari University of Venice, Venice, Italy* The World Meeting of the International Society for Bayesian Analysis (ISBA) will take place at Ca' Foscari University of Venice on July 1-7, 2024 ( http://www.unive.it/isba2024) and will be hosted by the Department of Economics and co-organized with the Venice centre in Economic and Risk Analytics (VERA, https://unive.it/vera) The meeting aims to bring together the international statistical community of researchers and professionals who develop Bayesian methods and apply them to challenging problems in different fields, ranging from economics, and finance, to business, industry, biostatistics, pharmaceutical statistics, environmental statistics, etc. *Lectures*: Dani Gamerman (Universidade Federal do Rio de Janeiro), Andrew Gelman (Columbia University), Kerrie Mengersen (Queensland University of Technology), Marina Vannucci (Rice University), Michael Jordan (University of California, Berkeley), Stephanie van der Pas (Amsterdam University Medical Center). *Keynote Speakers*: Antonietta Mira (USI and Università degli Studi dell'Insubria), Omiros Papaspiliopoulos (Bocconi University), Alexandra Schmidt (McGill University), Johannes Schmidt-Hieber (University of Twente). *Deadline for submitting contributed talks and posters: November 17, 2023. * Complete details regarding registration and accommodations will be available at the conference’s website at http://www.unive.it/isba2024 *Organizing Committee* Roberto Casarin (Chair), Ca’ Foscari University of Venice Emanuele Aliverti, University of Padua Isadora Antoniano Villalobos, Ca’ Foscari University of Venice Monica Billio, Ca’ Foscari University of Venice Guido Consonni, Catholic University of Milan Stefano Favaro, University of Turin Brunero Liseo, Sapienza University of Rome Sonia Petrone, Bocconi University of Milan Christian P. Robert, Université Paris Dauphine Stefano Tonellato, Ca’ Foscari University of Venice Laura Ventura, University of Padua *Scientific Committee* Sinead Williamson (Chair), University of Texas at Austin/Apple Sergios Agapiou, University of Cyprus Trevor Campbell, University of British Columbia Roberto Casarin, Ca’ Foscari University of Venice Luis Mauricio Castro Cepero, Pontificia Universidad Católica de Chile Christopher Drovandi, Queensland University of Technology Daniele Durante, Bocconi University Hedibert Freitas Lopes, Institute of Educatio and Research Emtiyaz Khan, RIKEN Center Matthias Katzfuss, University of Wisconsin-Madison Juhee Lee, University of California Santa Cruz David Nott, National University of Singapore Stéphanie van der Pas, Amsterdam UMC Bruno Sansó, University of California Mike West, Duke University -- 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

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Bandi assegni di ricerca presso POLIMI
by Laura Maria Sangalli 17 Oct '23

17 Oct '23

Vi prego di fare circolare il seguente avviso di bandi di assegni di ricerca SECS/S01 tra i potenziali interessati Bando di selezione per il conferimento di assegni di ricerca per lo svolgimento del programma di ricerca denominato: “STATISTICAL LEARNING PER IL PROGETTO GRINS – GROWING RESILIENT, INCLUSIVE AND SUSTAINABLE.WP2 PROGETTO GRINS – PNRR PE9 SPOKE7_2023_ASSEGNI_DMAT_14” Responsabili: Prof. Piercesare Secchi, Prof.ssa Francesca Ieva https://www.polimi.it/personale-docente/lavorare-al-politecnico/bandi-per-a… Scadenza: 18-10-23 Colloquio: 25-10-23 *** Bando di selezione per il conferimento di assegni di ricerca per lo svolgimento del programma di ricerca denominato: “MODELLI E ANALISI PER DATI CLINICI PROVENIENTI DA PROGETTI DELLE RETI CARDIOLOGICA E NEUROLOGICA.ATTIVITÀ WG6 PROGETTO HEALTH BIG DATA-PROTOCOLLO DI INTESA CON ALLEANZA CONTRO IL CANCRO_2023_ASSEGNI_DMAT_12” Responsabile: Prof.ssa Francesca Ieva https://www.polimi.it/personale-docente/lavorare-al-politecnico/bandi-per-a… Scadenza: 18-10-23 Colloquio: 26-10-23 —— Laura Maria Sangalli MOX - Dipartimento di Matematica Politecnico di Milano Piazza Leonardo da Vinci 32 20133 Milano - Italy (+39) 02 2399 4554 laura.sangalli(a)polimi.it<mailto:laura.sangalli@polimi.it> https://sangalli.faculty.polimi.it

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One World ABC Seminar: Stefan Radev - 26th October, 1pm Uk time
by Massimiliano Tamborrino 17 Oct '23

17 Oct '23

Dear all, our next One World ABC Seminar www.warwick.ac.uk/oneworldabc<http://www.warwick.ac.uk/oneworldabc> is quickly approaching. We are happy to inform you that our next OWABC speaker is Stefan Radev<https://faculty.rpi.edu/stefan-radev> (Rensselaer Polytechnic Institute, US), who will talk about "More expressive amortized Bayesian inference via joint learning and self-consistency?" on Thursday, the 26th October at 1pm UK time (please notice the different time!) Abstract: We propose “jointly amortized neural approximation” (JANA) to simultaneously learn intractable likelihood functions and posterior densities arising in Bayesian surrogate modeling and simulation-based inference. To this end, we train three complementary networks in an end-to-end fashion: 1) a summary network to compress individual data points, sets, or time series into informative embedding vectors; 2) a posterior network to learn an amortized approximate posterior; and 3) a likelihood network to learn an amortized approximate likelihood. The interaction between these networks opens a new route to amortized marginal likelihood and posterior predictive estimation. Furthermore, we observe that we can increase the efficiency of amortized inference by leveraging the marginal likelihood as a proxy for the self-consistency of Bayes’ rule. Upon perfect approximation, the marginal likelihood is constant across all parameter values by definition. However, approximation error leads to undesirable variance in the marginal likelihood estimates across different parameter values. We formulate violations of this symmetry as a loss function applicable in both likelihood-based and simulation-based scenarios. We demonstrate the utility of these approaches on illustrative Bayesian models, including both simple examples and representative cases. The talk will be streamed on MS Teams, and it can be joined via this link https://teams.microsoft.com/l/meetup-join/19%3ameeting_ZWQwZjg3NTktNjY4OS00… or via Meeting ID: 389 057 974 73 Passcode: H9uMjk We're looking forward to seeing you next week, best, Massimiliano on the behalf of the OWABC Organisers ------ Dr. Massimiliano Tamborrino Associate Professor Department of Statistics University of Warwick https://warwick.ac.uk/tamborrino

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Seminario a Napoli
by epirozzi 16 Oct '23

16 Oct '23

Avviso di Seminario il giorno 25 Ottobre 2023 alle ore 14:30 Anna Vidotto Dipartimento di Matematica e Applicazioni Università degli studi di Napoli FEDERICO II terrà un seminario dal Titolo: The Malliavin-Stein Approach and an Improved Second-Order Poincaré Inequality. Abstract: In this talk we will introduce the so-called Malliavin-Stein approach for obtaining quantitative central limit theorems for functionals of Gaussian fields, that this combination works admirably well was discovered by Nourdin and Peccati in their seminal paper from 2009. Then we will present an improved version of the second-order Gaussian Poincaré inequality, first introduced in Chatterjee (2009) and Nourdin et al. (2009), and consequent applications. Il seminario si terrà nella Sala Professori Primo livello al Dipartimento di Matematica e Applicazioni, Università degli Studi di Napoli FEDERICO II, Complesso di Monte Sant'Angelo, Via Cintia, Napoli. Sarà anche possibile seguirlo online mediante Teams al seguente link: https://teams.microsoft.com/l/meetup-join/19%3aMQ4RZDBo_0G-K_PHxKtktVYAczOG… -- Enrica Pirozzi Professore Associato di Probabilità e Statistica, Dipartimento di Matematica e Applicazioni, Università di Napoli FEDERICO II Via Cintia, 80126, NAPOLI https://www.docenti.unina.it/enrica.pirozzi

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Double seminar: Francesco D'Amore & Isabella Ziccardi at Tor Vergata
by Michele Salvi 16 Oct '23

16 Oct '23

Dear all, On Thursday, October 19th, at 14h00 (change of usual time!) in Aula Dal Passo at the Math Department of Roma Tor Vergata, RoMaDS (https://www.mat.uniroma2.it/~rds/about.php) will host the seminars 14h00 - Francesco D'Amore (Aalto University, Espoo) "The Strong Lottery Ticker Hypothesis and the Random Subset Sum Problem” Abstract: The Strong Lottery Ticket Hypothesis (SLTH) posits that randomly-initialized neural networks contain subnetworks (strong lottery tickets) that achieve competitive accuracy when compared to sufficiently small target networks, even those that have been trained. Empirical evidence for this phenomenon was first observed by Ramanujan et al. in 2020, spurring a line of theoretical research: Malach et al. (2020), Pensia et al. (2020), da Cunha et al. (2022), and Burkholz (2022) have analytically proved formulations of the SLTH in various neural network classes and under different hypotheses. In this presentation, we provide an overview of the state-of-the-art theoretical research on the SLTH and its connection with the Random Subset Sum (RSS) problem in theoretical computer science. While previous works on the SLTH ensure that the strong lottery ticket can be obtained via unstructured pruning, we demonstrate how recent advances in the multidimensional generalization of the RSS problem can be leveraged to obtain forms of structured pruning. Additionally, we highlight how refining the RSS results would yield tighter formulations of the SLTH. This presentation is based on a joint work with Arthur da Cunha and Emanuele Natale that will be presented at NeurIPS 2023. 15h00 - Isabella Ziccardi (Bocconi) "Distributed Self-Stabilizing MIS Algorithms" Abstract: I will discuss self-stabilizing distributed algorithms that find a Maximal Independent Set in an n-vertex graph. These algorithms share the feature of utilizing randomization to break symmetry. I will compare them based on the following parameters: the number of states used by each node, the knowledge of the graph required by each node, and their stabilization time. The first three algorithms are obtained by reconsidering some existing algorithms and making them self-stabilizing by introducing additional states. The first algorithm gets along with three states, but each node must have knowledge of ∆, the maximum node degree. In the second algorithm, nodes only need to be aware of their degree, but each node v has O(∆(v)) states, where ∆(v) is the degree of v. The third algorithm also requires O(∆(v)) states for each node v, but it works in the restricted beeping communication model. All three algorithms stabilize in O(log n) rounds with high probability. Lastly, I will talk about two algorithms that aim to create self-stabilizing algorithms with a constant number of states while requiring no knowledge of the underlying graph. The first algorithm is a natural process that, despite its simplicity, has received limited attention in the literature. It stabilizes in O(polylog(n)) rounds for specific graph families but may exhibit slower convergence time on general graphs. The final algorithm is a modification of this simple process, that tries to fix the particular situations that slow down the convergence. We encourage in-person partecipation. Should you be unable to come, here is the link to the Teams streaming: https://teams.microsoft.com/l/meetup-join/19%3arfsL73KX-fw86y1YnXq2nk5VnZFw…"Tid"%3a"24c5be2a-d764-40c5-9975-82d08ae47d0e"%2c"Oid"%3a"650fc4a8-4cec-4bd2-87bc-90d134074fe6"} <https://teams.microsoft.com/l/meetup-join/19%3arfsL73KX-fw86y1YnXq2nk5VnZFw…> The seminar is part of the Excellence Project MatMod@TOV.

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