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Seminario Leonardo Lelli
by De Santis, Emilio 30 Jan '24

30 Jan '24

Cari, vi scrivo per annunciare il seminario di Leonardo Lelli il 2 febbraio 2024 alle ore 14 in Sala di Consiglio presso il Dipartimento di Matematica Guido Castelnuovo, Sapinza Università di Roma, Piazzale Aldo Moro, 5 Roma ............................................................................................................. Title Zero-temperature stochastic Ising model on quasi-transitive graphs Abstract We examine the question of fixation for zero-temperature stochastic Ising model on some connected quasi-transitive graphs. The initial spin configuration is distributed according to a Bernoulli product measure with parameter $p\in (0,1) $. We prove that the shrink property for the underlying graph is a necessary condition for all sites to flip infinitely often almost surely (in this case the model is said of type I). Our main result shows that if $p=1/2 $ and the graph is connected and invariant under rotations and translations, then a strengthening of the shrink property, called the planar shrink property, implies that the model is of type I. We provide an infinite class of graphs having the planar shrink property. Finally, we prove that for one-dimensional translation invariant graphs, the shrink property is a necessary and sufficient condition for the model to be of type I. This talk is based on joint work with my thesis advisor Emilio De Santis. ............................................................................................. Cordiali saluti, Emilio De Santis

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Nuovi Seminari PRISMA - 5 feb 2024
by Francesco Caravenna 30 Jan '24

30 Jan '24

Nuovi Seminari PRISMA 2024 Annunciamo con piacere il nuovo programma di seminari on-line del gruppo UMI - PRISMA (PRobability In Statistics, Mathematics and Applications: http://www.umi-prisma.polito.it/) Da quest'anno i seminari avranno un formato diverso, in uno stile di "colloquium", per creare un'occasione di scambio e discussione con tutta la comunità dei probabilisti e statistici italiani. Ogni giornata comprenderà due relatori, che terranno due seminari di 30 minuti strettamente connessi, per presentare alla comunità una prospettiva sul proprio ambito di ricerca. Il primo appuntamento si terrà lunedì 5 febbraio 2024. I relatori saranno Sandra Fortini (Università Bocconi) e Dario Trevisan (Università di Pisa) che presenteranno Un'introduzione ai limiti di scala delle reti neurali artificiali con il seguente orario: 16:00 Primo seminario 16:30 Pausa e discussione 16:45 Secondo seminario 17:15 Conclusione e discussione Trovate di seguito il riassunto. I seminari verranno trasmessi via Zoom al seguente link: https://uniroma1.zoom.us/j/82939128330 <https://uniroma1.zoom.us/j/82939128330> Meeting ID: 829 3912 8330 Vi aspettiamo numerosi! Valentina Cammarota e Francesco Caravenna %%%%%%%%%%%%%%%%%%%%%%%%%%%% RELATORI: Sandra Fortini (Università Bocconi), Dario Trevisan (Università di Pisa) TITOLO: Un'introduzione ai limiti di scala delle reti neurali artificiali RIASSUNTO: Il seminario si propone di presentare un'introduzione alla teoria dei limiti di scala delle reti neurali artificiali, con un'attenzione particolare rivolta a un pubblico esperto di probabilità e statistica matematica. La tendenza attuale nel campo dell'apprendimento automatico è di utilizzare reti neurali profonde con un numero enorme di parametri, inizializzati spesso in modo (pseudo-)casuale. Questo approccio, che nella pratica si rivela estremamente efficace, offre anche una prospettiva teorica utile per comprendere alcune delle proprietà che rendono tale tecnica così potente, ma anche di evidenziarne possibili limiti. L'intervento sarà suddiviso in due parti, ciascuna incentrata su un aspetto del tema. Dopo una breve introduzione alle reti neurali artificiali e al loro utilizzo pratico nell'apprendimento automatico, la prima parte si concentrerà sulla struttura delle reti all'inizializzazione, limitandoci per semplicità alle architetture più semplici. Esploreremo in più dettaglio alcuni dei risultati principali riguardanti i limiti di scala ``ampio'' e ``profondo'' per reti neurali inizializzate con pesi casuali, concentrandoci su alcuni risultati recenti che stabiliscono una equivalenza asintotica tra reti neural profonde e opportuni processi gaussiani. Nella seconda parte, ci concentreremo sulla dinamica dell'addestramento delle reti neurali. Dopo una breve panoramica sui principali algoritmi utilizzati in scenari reali, ci concentreremo su alcuni dei risultati teorici rigorosi, validi per reti ampie e/o profonde: descriveremo in particolare la dinamica guidata dal Neural Tangent Kernel (NTK) nel limite dell'addestramento ``lazy'' e la dinamica di gradiente di Wasserstein nel limite di campo medio. %%%%%%%%%%%%%%%%%%%%%%%%%%%%

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6 feb 2024 - Seminario Dr. Luca Gonzato
by Enea Bongiorno 30 Jan '24

30 Jan '24

Carissimi colleghi, scusandomi per eventuali invii multipli, vi inoltro il seguente annuncio di seminario. Tutti gli interessati sono invitati a partecipare. Cordialmente, Enea Bongiorno -------------------------------- 6 febbraio 2024 ore 14.00 - aula 206, campus Perrone, via Perrone, 18, Novara. Università del Piemonte Orientale. - on-line: http://meet.google.com/cto-jsdt-pay *Title*: Bayesian Calibration of Option Pricing Models Dr. Luca Gonzato, University of Vienna, Department of Statistics and Operations Research *Abstract*: Calibration of option pricing models to the implied volatility surface is a complicated, yet fundamental task in the quantitative finance community. By exploiting Sequential Monte Carlo (SMC) methods we turn the standard calibration problem into a Bayesian estimation task. In this way we can construct a sequence of distributions from the prior to the posterior which allows to compute any statistic of the estimated parameters, to overcome the strong dependence on the starting point and to avoid troublesome local minima; all of which are typical plagues of the standard calibration. To highlight the strength of our approach we consider the calibration of the double jump stochastic volatility model of Duffie et. al (2000) both on simulated and real option data. From the results on both single dates and time series of implied volatilities we find that our Bayesian approach largely outperforms the benchmark in terms of run time-accuracy, option pricing errors and statistical fit. Finally, we show how to further speed up computations by leveraging delayed-acceptance MCMC methods and deep learning. This is a joint work with R. Brignone, S. Knaust and E. Lutkebohmert, University of Friburg. ----------------------------------- Locandina dell'evento <https://drive.google.com/file/d/1cafNljjg5n3KSS9laizaryY8nkX6O6GD/view?usp=…> Seminari Matematici Statistici <https://sites.google.com/uniupo.it/seminari-ms/home-page> ----------------------------------- -- Enea Bongiorno, Università degli Studi del Piemonte Orientale Via Perrone 18, 28100, Novara, Italia Phone: +390321375317 enea.bongiorno(a)uniupo.it upobook.uniupo.it/enea.bongiorno

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Bando assegno di Ricerca MAT/06 a Napoli
by epirozzi 29 Jan '24

29 Jan '24

Si segnala il seguente bando per assegno di Ricerca presso il Dipartimento di Matematica e Applicazioni dell'Università di Napoli FEDERICO II con scadenza il 31 gennaio 2023 http://www.unina.it/documents/11958/48570136/DMA_AR-13_2023-12-11_bando.pdf Cari saluti Enrica -- 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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Seminar in Statistics - LUCA TRAPIN
by Pierpaolo De Blasi 29 Jan '24

29 Jan '24

SEMINARS IN STATISTICS @ COLLEGIO CARLO ALBERTO <https://www.carloalberto.org/events/category/seminars/seminars-in-statistic…> Venerdi 2 Febbraio 2024, alle ore 12.00, presso il Collegio Carlo Alberto, in Piazza Arbarello 8, Torino, si terrà il seguente seminario: ------------------------------------------------ Speaker: Luca Trapin (Università di Bologna) Title: *Tail index regression forest* Abstract: Regression analysis of the tail index has received increasing attention over the last few years. The availability of large and complex datasets has stimulated the development of tail index regression techniques that can capture complex relationships between a large number of predictors and a dependent variable of interest. However, available methods are either flexible and asymptotically justified but do not scale well with the dimension of the predictor space, or well-suited in high-dimension but lack asymptotic results. This paper presents a novel random forest approach that fills this gap. We establish the asymptotic normality of our tail index regression forest estimator under mild assumptions on the tail behavior of the dependent variable. An extensive simulation study and an application to the conditional distribution of ROE for a large cross-section of U.S. companies confirm that our approach outperforms existing parametric and non-parametric tail index regression methods. ------------------------------------------------ Sarà possibile seguire il seminario anche in streaming: Join Zoom Meeting <https://us02web.zoom.us/j/82054178592?pwd=NHI1RHBLYnUwVUFoSW9HSVhUN3F6dz09> 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/>

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De Finetti Risk Seminar: Giorgio Ferrari
by Marco Maggis 26 Jan '24

26 Jan '24

On behalf of the Scientific Committee of the "B. de Finetti Risk Seminars, Milano Lectures on the Mathematical Theory of Economics and Finance”, we are glad to invite you to participate at the following lecture: Giorgio Ferrari Bielefeld University Title: Stationary Mean-field Games with Singular Controls Abstract: In this talk I will present recent and ongoing results on existence, uniqueness, and characterization of equilibria for mean-field games with singular controls. This class of problems finds natural applications in Economics and Finance, such as in investment problems in oligopolies. In those games, the representative agent employs a bounded-variation control in order to maximize an ergodic profit functional depending on a long-time average of the controlled state-process. Several variants of the considered games will be presented, ranging from one-dimensional settings to multi-dimensional ones. LOCATION: The seminar will be held on *February 7, *2024 at *17.00,* Aula 10 (First Floor), Dipart. Matematica, Università di Milano, Via Saldini 50, Milano. Scientific Committee: Prof. Simone Cerreia-Vioglio (Univ. Bocconi) Prof. Marco Frittelli (Univ. degli Studi di Milano) Prof. Fabio Maccheroni (Univ. Bocconi) Prof. Marco Maggis (Univ. degli Studi di Milano) Prof. Massimo Marinacci (Univ. Bocconi) Prof. Emanuela Rosazza Gianin (Univ. Milano-Bicocca)

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Announcement - SPDE conference in Delft
by Antonio Agresti 25 Jan '24

25 Jan '24

Dear All, July 1st-July 5th 2024, there will be a stochastic PDE conference in Delft (Netherlands), titled "*SPDEs below sea level*". See also the website https://www.spde-delft2024.com/ . There is a great selection of speakers and there will be talks related to many aspects of SPDE, including well-posedness, regularity, numerical approximation, large deviations etc. If you are interested in attending the conference, then please register via the Google form on our website. Feel free to send me an email if you would like to have more information. Please note that there is a limited number of places for participants. Please register as soon as possible if you are interested in attending the conference. It is still unclear if there is room for additional talks at the conference. On behalf of the organizing committee, best regards, Antonio Agresti

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SOfA conference 2024 - second announcement
by Mastrogiacomo Elisa 24 Jan '24

24 Jan '24

Apologies in advance for cross-posting *** Dear Colleagues, The University of Insubria and Bicocca are honored to host the next international academic conference in the fields of vector and set optimization, stochastic analysis, risk management, and operation research — the 6th International Conference on Set Optimization for Applications (SOfA 2024). This edition is going to take place in Stresa from June 3 to June 7, 2024. The 6th SOfA aims to bring together experts in various fields of set and vector optimization, convex and variational analysis, stochastic analysis, multivariate dynamic programming, multi-criteria decision-making, as well as applications in economics, risk measurement, game theory, and statistics. The conference is, by tradition, very open; the scientific and local committees long to move outside the stream of set and vector optimization and bring together people with a research record in set optimization, with some maybe only remotely related to this topic. So, a very mixed and curious audience is expected. Join us also for a scenic cruise trip on Lago Maggiore and savor the spectacle of its famous islands! We enthusiastically invite all researchers, practitioners, and students in the field described above and related areas to submit proposals for presentations at the 6th SOfA conference. Abstract submission and conference registration are now open! The 6th SOfA also features a couple of tutorials on dynamic programming and stochastic optimal control, and on solution concepts in set-optimization on June 3rd. For more information about the conference, please visit our conference website<https://sites.google.com/view/sofa2024/programme?authuser=0>. If you have any questions, feel free to get in touch with us at sofa2024.conference(a)gmail.com<mailto:sofa2024.conference@gmail.com>. **Given the high tourist demand in June, we strongly recommend booking as soon as possible. Availability is not guaranteed for last-minute bookings, and rates will increase as the conference start date approaches.** We look forward to your active participation in making the 6th SOfA a diverse and engaging conference for knowledge exchange. Regards, The 2024 SOfA Organizing Committees Elisa Mastrogiacomo ----------------------------------------- Professore Ordinario di Metodi matematici dell'economia e delle scienze attuariali e finanziarie DIPARTIMENTO D'ECCELLENZA 2023/2027 Università degli Studi dell'Insubria Dipartimento di Economia Via Monte Generoso, 71 – 21100 Varese tel. +39 0332/395528 web: www.uninsubria.it<http://www.uninsubria.it/> mail: elisa.mastrogiacomo(a)uninsubria.it<mailto:mario.rossi@uninsubria.it> Chiaramente Insubria! [LOGO-ATENEO-FONDO TRASPARENTE]<http://www.uninsubria.it/> [Facebook] <https://www.facebook.com/uninsubria> [Twitter] <https://twitter.com/Uni_Insubria> [Instagram] <https://instagram.com/uninsubria> [YouTube] <https://www.youtube.com/user/LabVAMultimedia>

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PhD position in Probability at TU Vienna
by Prof. Fabio Toninelli 24 Jan '24

24 Jan '24

Dear colleagues, the Technical University of Vienna is advertising a 4-year PhD position (pre-doctoral assistant) in the research group of Probability theory (https://www.tuwien.at/en/mg/mstoch) Application deadline: February 15, 2024. Link for details and to application portal: https://jobs.tuwien.ac.at/Job/226172 Starting date of the position: October 2024. Best wishes Fabio Toninelli -- Prof. Dr. Fabio Toninelli Technical University of Vienna Institut für Stochastik und Wirtschaftsmathematik Wiedner Hauptstrasse 8-10, 1040 Wien, Austria Office: 6th floor, green area. tel: +43-1-58801-10570 https://sites.google.com/view/fabio-toninelli/home

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Call for applications - MAPPA double degree master program - Padova & Paris Dauphine
by Claudio Fontana 24 Jan '24

24 Jan '24

Dear colleagues, I would like to draw your attention to the call for applications for the MAPPA program, a DOUBLE DEGREE MASTER PROGRAM IN MATHEMATICS offered jointly by the UNIVERSITY OF PADOVA and PARIS DAUPHINE UNIVERSITY (Paris Sciences & Lettres). This two-year program features three study paths: - Mathematical Analysis - Probability and Finance - Probability and Statistical Mechanics The admitted students will spend the first year in Padova and the second year in Paris. Upon successful completion, students will be awarded two degrees: Laurea Magistrale in Matematica (from Padova) and Master in Mathematics and Applications (from Paris Dauphine). The master thesis will be conducted in collaboration with two supervisors, one in Padova and one in Paris. Admission to the program, limited to 10 students, will be based on CV, presentation letters, and an interview. Financial support and fellowships are available for admitted students. For more detailed information on the MAPPA program, please visit: https://web.math.unipd.it/mappawp The call for applications (bando) can be found here: https://www.math.unipd.it/news/bando-di-concorso-n-1-2024-per-10-posti-per-… The _DEADLINE FOR APPLICATIONS_ is MAY 13, 2024, AT 12:00 PM. Kindly inform your (brilliant) bachelor students about the MAPPA program, and feel free to contact me for further information. Best Regards, Claudio Fontana

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