September 2021 - Random - Mailing list — Dipartimento di Matematica, UniPI

[owps] OWPS, October 7th: P. Diaconis and L. Miclo on "THE random graph" (fwd)
by Michele Gianfelice 24 Sep '21

24 Sep '21

Salve, ricevo ed inoltro p.c.. Cordialmente, m.gianfelice ----------------------------------------------------------------------- Michele Gianfelice, PhD Dipartimento di Matematica e Informatica Università della Calabria Telephone : +39 0984 496412 Campus di Arcavacata Fax : +39 0984 496410 Ponte P. Bucci - cubo 30B email: gianfelice(a)mat.unical.it I-87036 Arcavacata di Rende (CS) www.mat.unical.it/~gianfelice/ ----------------------------------------------------------------------- ---------- Forwarded message ---------- Date: Thu, 23 Sep 2021 20:43:34 +0200 From: One World Probability <ow.probability(a)gmail.com> To: owps(a)lists.bath.ac.uk Subject: [owps] OWPS, October 7th: P. Diaconis and L. Miclo on "THE random graph" Dear probabilists, We are pleased to inform you that the OWPS will resume on October 7th, from 14:00 to 15:45 UTC. Persi Diaconis and Laurent Miclo will talk about THE random graph and random walk on it. Titles, abstracts and the Zoom link are below the signature, and can be found on the website https://www.owprobability.org/one-world-probability-seminar. We also inform you that, in accordance with the wishes expressed in the pooling, sessions will take place every other week (i.e. ~2 per month). Each session will consist of two talks of 45 minutes each. These two talks will be thematically unified. Please feel free to circulate this email. Probabilistically yours, Bastien Mallein and Sébastien Martineau -------- Persi Diaconis -- Probability theory for THE random graph Pick two Erdös-Renyi (n,1/2) graphs uniformly at random. What's the chance they are the same (isomorphic)? Small. How small? Well, at most n!/ 2^(n choose 2). When n= 100, that's less than 10^-1300. OK, now let n=infinity. The chance that the two graphs are isomorphic is one (!). This is THE random graph (the Rado graph R). I will review its many non-random models and many strange properties. ? It is a natural limit of the set of all finite graphs (a first order property is true for almost all finite graphs if and only if it holds with probability one in R) and this discontinuity is surprising. In joint work with with Sourav Chatterjee we tried to find finite manifestations: For finite n, the largest isomorphic induced subgraph of a pair has size 4log (n) -2loglog(n)-2log(4/e) +1 (within 1, all logs base 2 in probability when n is large). This matches data amazingly well (e.g. for n more than 30) and illuminates problems in constraint satisfaction. Laurent Mico -- A random walk on THE random graph R Let q(j) be a probability on N={0,1,2,...}. Let R be a model of THE random graph. A Markov chain on N starts at i and moves to one of its neighbor j in R with probability proportional to q(j). This Markov chain has a stationary distribution and we inquire about rates of convergence. Since each vertex is connected to half of the others and the diameter of R is 2, it seems likely that convergence is fast. In some models we show that log* (i) steps are necessary and sufficient for convergence. The proof uses a novel variant of Hardy's inequalities for trees. This is joint work with Sourav Chatterjee and Persi Diaconis. Zoom-link: https://us02web.zoom.us/j/81721277245?pwd=VjhadGFZcTVZamsvRkhZUExVbHAyZz09 Meeting ID 817 2127 7245 Passcode: 759491 If you are having trouble with zoom, or if the capacity of the zoom room gets exceeded, you can also access to the Youtube live stream at the channel of the seminar: https://www.youtube.com/channel/UCiLiEQGTp6bZEhuHDM-WNWQ

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Workshop "Deterministic and stochastic fractional diﬀerential equations and jump processes"
by Enrico Scalas 22 Sep '21

22 Sep '21

Care colleghe e cari colleghi, nell'ambito del programma "Fractional Differential Equations" ( https://www.newton.ac.uk/event/fde2/) che si terrà all'Isaac Newton Institute a Cambridge, organizzo una settimana di studi su "Deterministic and stochastic fractional diﬀerential equations and jump processes" (https://www.newton.ac.uk/event/fd2w01/) insieme a Jozsef Lorinczi e Vassili Kolokoltsov. L'evento avrà luogo tra il 21 febbraio e il 25 febbraio 2022 (ed è ora possibile registrarsi fino al 21 novembre 2021) e si terrà in modalità ibrida (online e con persone presenti, se possibile). La partecipazione online è gratuita. Per i dettagli potete consultare il sito seguente: https://www.newton.ac.uk/event/fd2w01/ Cordiali saluti, Enrico Scalas

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(PMS)^2 online talk: Hakima Bessaih, Monday September 27 at 17.30
by Margherita Zanella 22 Sep '21

22 Sep '21

Dear colleagues, we are happy to announce the following online talk: Speaker: Hakima Bessaih (Florida International University) Title: Numerical schemes for the 2d Stochastic Navier-Stokes equations. Abstract: We consider a time discretization scheme of Euler type for the 2d stochastic Navier-Stokes equations on the torus. We prove a mean square rate of convergence. This refines previous results established with a rate of convergence in probability only. Using exponential moment estimates of the solution of the Navier-Stokes equations and a convergence of a localized scheme, we can prove strong convergence of fully implicit and semi-implicit time Euler discretization and also a splitting scheme. The speed of convergence depends on the diffusion coefficient and the viscosity parameter. When the noise is additive, we are able to get strong convergence without localization. Date and time: Monday September 27, 17:30-18:30 (Rome time zone) Zoom link: https://us02web.zoom.us/j/5772228296 This is a talk of the (PMS)^2: Pavia-Milano Seminar series on Probability and Mathematical Statistics organized jointly by the universities Milano-Bicocca, Pavia, Milano-Politecnico and Milano-Statale. For more information see the dedicated webpage: https://paviamilanoseminars.wordpress.com/<http://paviamilanoseminars.wordpress.com/> Participation is free and welcome! (though limited to 100 participants for technical reasons). Best regards The organizers (Mario Maurelli, Carlo Orrieri, Maurizia Rossi, Margherita Zanella)

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Seminars by Jim Gatheral, Baruch College CUNY New York
by Giacomo Bormetti 21 Sep '21

21 Sep '21

Dear all, Prof. Jim Gatheral is visiting the Department of Mathematics in Bologna for the next two months. On September 29 and October 13 he will deliver two seminars in presence in Bologna in Aula Cremona, main building of the Math Department. You are all kindly invited. It will be possible to follow the seminars online via Zoom too (please find below the links to connect). Sincerely, Giacomo Bormetti and Fabrizio Lillo 29-Sep-2021 16:00 (CET time) Aula Cremona, Department of Mathematics or Zoom https://unibo.zoom.us/j/99763851456?pwd=YzVBMTNxUXpRWngrNExaRWtMRjRkdz09 Title: Diamond trees and the forest expansion Abstract: I will present a “broken exponential martingale” G-expansion that generalizes and unifies our earlier exponentiation result (Alòs, Gatheral, and Radoičić) and the cumulant recursion formula of Lacoin, Rhodes, and Vargas. As one application, I show how to compute all terms in an expansion of the Lévy area. By reordering the trees in the G-expansion according to the number of leaves, our earlier exponentiation theorem can be recovered. As further applications, I will give model-free expressions for various quantities of interest under stochastic volatility. Finally, I will exhibit explicit computations of diamond trees under rough Heston. 13-Oct-2021 16:00 (CET time) Aula Cremona, Department of Mathematics or Zoom https://unibo.zoom.us/j/91206042957?pwd=d21ybkJQTEtkZHRWd25RLzJOQWV0QT09 Title: Pricing in affine forward variance models Abstract: The class of affine forward variance (AFV) models was defined in Gatheral and Keller-Ressel (2019); this class includes both the conventional Heston model and its celebrated extension, the rough Heston model of El Euch and Rosenbaum. The AFV characteristic function may be expressed in terms of the solution of a Volterra integral equation. I will present a rational approximation to the solution of this integral equation in the special case of the rough Heston model. Until now, simulation of AFV models using the Markovian approximation of Abi Jaber and El Euch has proved relatively complicated and time-consuming, I will present a new efficient and easy-to-implement method for simulating AFV models for general kernels. I will present numerical results using the rational approximation as a benchmark.

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virtual seminar in Insubria & Bicocca
by Emanuela Rosazza Gianin 21 Sep '21

21 Sep '21

Dear all, On *September 30 at 17:00, Giulia Di Nunno* (University of Oslo) will give a virtual seminar “in Insubria & Bicocca”, to which you are all invited. You can find the title and abstract below. Title: Infinite dimensional Heston model and sensitivity analysis Abstract: We consider the infinite dimensional Heston stochastic volatility model for the price of a forward contract on a non-storable commodity. We give a representation formula for the forward price and then we consider options written on this. We analyse the sensitivity of the option price to the different parameters in the model with the aim at providing representation formulae for the so-called Greeks. However, being the parameter infinite dimensional, we need to reinterpret the meaning of the Greeks. In our work we use infinite dimensional Malliavin/Skorokhod calculus and a randomisation technique. The presentation is based on joint work with Fred Espen Benth and Iben Simonsen. The seminar will be on *Zoom*. You can find the information to join below. Speaker: Giulia Di Nunno (Univ. Oslo) Topic: Time: September 30, 2021 05:00 PM Rome Where: Zoom Link: https://us02web.zoom.us/j/86037568156?pwd=cHhvdmdiWUpVYXFjMEo2RWZxM09Rdz09 ID riunione: 860 3756 8156 Passcode: 086446 After the talk, you are all invited to remain in the meeting for an informal aperitif and chat. Please forward to anyone interested. Kind regards, Elisa Mastrogiacomo and Emanuela Rosazza Gianin ****************************************** Emanuela Rosazza Gianin Department of Statistics and quantitative methods University of Milano-Bicocca Via Bicocca degli Arcimboldi, 8 20126 Milano - Italy Phone (0039) 02 64483208 e-mail: emanuela.rosazza1(a)unimib.it ******************************************

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Concorso RTDB MAT06 scadenza 30 settembre
by Gustavo Posta 20 Sep '21

20 Sep '21

Scusandomi per il breve preavviso inoltro il link relativo al bando in oggetto. > > https://web.uniroma1.it/trasparenza/sites/default/files/DR%202267_2021%20de… <https://web.uniroma1.it/trasparenza/sites/default/files/DR%202267_2021%20de…> ---------------------------------------------------------------- Gustavo Posta Dipartimento di Matematica Università di Roma "la Sapienza" P.le A. Moro 2, 00185 Roma Italy web: http://www1.mat.uniroma1.it/~posta e-mail: gustavo.posta(a)uniroma1.it phone: +39-06-4991-4969 ------------------------------------------------------------------ -- ________________________________________________________ Le informazioni contenute in questo messaggio di posta elettronica sono strettamente riservate e indirizzate esclusivamente al destinatario. Si prega di non leggere, fare copia, inoltrare a terzi o conservare tale messaggio se non si è il legittimo destinatario dello stesso. Qualora tale messaggio sia stato ricevuto per errore, si prega di restituirlo al mittente e di cancellarlo permanentemente dal proprio computer. The information contained in this e mail message is strictly confidential and intended for the use of the addressee only. If you are not the intended recipient, please do not read, copy, forward or store it on your computer. If you have received the message in error, please forward it back to the sender and delete it permanently from your computer system. -- Fai crescere i nostri giovani ricercatori dona il 5 per mille alla Sapienza *codice fiscale 80209930587*

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[MAF2022] First call for paper - Conference on Mathematical and Statistical Methods for Actuarial Sciences and Finance
by Marco Corazza 20 Sep '21

20 Sep '21

Dear Colleague, we are writing for informing you that the *10th Conference on Mathematical and Statistical Methods for Actuarial Sciences and Finance - MAF2022* will take place at the University of Salerno (Italy), on April, 20-22, 2022, in a blended form. The main aim of the Conference is to present new theoretical and methodological results and significant applications in Insurance and Finance by means of the capabilities of the interdisciplinary mathematical-statistical approach. The web site of the Conference is *https://sites.google.com/unisa.it/maf2022/home-page <https://sites.google.com/unisa.it/maf2022/home-page>*. The Steering Committee of the Conference would appreciate very much if you could collaborate in the success of the conference by participating in some activities such as the organization of sessions and/or the presentation of contributions (also through a co-author). We hope to meet you at the conference. Best regards, Marco Corazza - Ca' Foscari University of Venice (Italy) Cira Perna - University of Salerno (Italy) Claudio Pizzi - Ca' Foscari University of Venice (Italy) Marilena Sibillo - University of Salerno (Italy) -- Marco Corazza, Ph.D. Department of Economics - Ca' Foscari University of Venice San Giobbe, Cannaregio 873 - 30121 Venezia, Italy Mobile: (+39) 366 602-9134 Phone: (+39) 041 234-6921 Fax: (+39) 041 234-7444 E-mail: corazza(a)unive.it Editor-in-Chief: Mathematical Methods in Economics and Finance - www.unive.it/m2ef

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special issue on Anomaly Detection: methods and applications
by Daniela De Canditiis 20 Sep '21

20 Sep '21

dear all, we cordially invite you to submit a manuscript to the following special issue Special Issue: Methods and Applications for Anomaly Detection Journal of Computational Mathematics and Data Science (Elsevier) https://www.journals.elsevier.com/journal-of-computational-mathematics-and-… Submission Deadline: 31 July 2022 Manuscripts can be submitted continuously until the deadline. Once a paper is submitted, the review process will start immediately. Accepted papers will be published continuously in the journal. There are no publication fees until March 2022. ********* This Special Issue is focused on recent advances in Anomaly Detection (AD). AD is an important problem in many applications and it consists of establishing whether a given data deviates from nominal shape or form. The AD problem depends on the nature of input data (points, sequences, functions, graphs, images, objects of different nature), on the type of anomaly (point anomalies, contextual or behavioral anomalies or their combination), on the availability of labeled data for training/validation of the AD techniques (leading to unsupervised AD and supervised AD), and on the type of output of the AD (scores or label). Some of the topics of interest include (but are not limited to): Classification techniques Robust regression Robust PCA Robust signal processing Robust image processing Clustering techniques Information theory techniques Artificial Intelligence AD Application to any field ********* Manuscript submission information: Guest Editors: Annalisa Pascarella (IAC-CNR, Italy) Daniela De Canditiis (IAC-CNR, Italy) The submission website for this journal is located at: https://www.editorialmanager.com/jcmds/default.aspx To ensure that all manuscripts are correctly identified for inclusion into the special issue, it is important that authors select VSI: Anomaly Detection (Special Issue) when they reach the “Article Type” step in the submission process. We look forward to hearing from you. All the best, Annalisa Pascarella Daniela De Canditiis -- Daniela De Canditiis, PhD Istituto per le Applicazioni del Calcolo "M.Picone" (CNR) via dei Taurini, 19 -- 00185 Roma, Italy tel: +39 06 49937342 fax: +39 06 4404306 http://www.iac.rm.cnr.it/~danielad/

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Seminario di Lorenzo Dello Schiavo a Roma La Sapienza
by Faggionato, Alessandra 16 Sep '21

16 Sep '21

Buongiorno sotto trovate le informazioni sul seminario di Lorenzo dello Schiavo a Roma 1. Grazie dell'attenzione Saluti Alessandra Quando: Martedì 21 Settembre 2021, ore 10.30 Dove: Sala di Consiglio, Dipartimento di Matematica, Università La Sapienza Speaker: Lorenzo Dello Schiavo (IST Austria) Title: *Conformally invariant random fields, quantum Liouville measures, and random Paneitz operators on Riemannian manifolds of even dimension* Abstract: On large classes of closed even-dimensional Riemannian manifolds M, we construct and study the *Copolyharmonic Gaussian Field*, i.e. a conformally invariant log-correlated Gaussian field of distributions on M. This random field is defined as the unique centered Gaussian field with covariance kernel given as the resolvent kernel of Graham—Jenne—Mason—Sparling (GJMS) operators of maximal order. The corresponding Gaussian Multiplicative Chaos is a generalization to the 2m-dimensional case of the celebrated Liouville Quantum Gravity measure in dimension two. We study the associated Liouville Brownian motion and random GJMS operator, the higher-dimensional analogues of the 2d Liouville Brownian Motion and of the random Laplacian. Finally, we study the Polyakov–Liouville on the space of distributions on M induced by the copolyharmonic Gaussian field, providing explicit conditions for its finiteness and computing the conformal anomaly. (arXiv:2105.13925 <https://arxiv.org/abs/2105.13925>, joint work with Ronan Herry, Eva Kopfer, Karl-Theodor Sturm) ************************************************* Prof. Alessandra Faggionato http://www1.mat.uniroma1.it/~faggionato/ Department of Mathematics University "La Sapienza" Piazzale Aldo Moro, 5 00185 - Rome Office 5, Phone (0039) 06 49913252 *************************************************

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One World Optimal Stopping and Related Topics
by Tiziano De Angelis 15 Sep '21

15 Sep '21

Dear All, It is with great pleasure that we announce the September-December schedule of the “One World Optimal Stopping and Related Topics” seminars (online). Detailed information and instructions for registration are available at https://sites.google.com/view/optimalstopping/home Please register again, even if you had already registered in the past academic year. Our first speaker on Wednesday 22 September at 5pm (London time) is: Damien Lamberton, Université Gustave Eiffel Title of the talk: On the American put in the Heston model Best wishes Tiziano De Angelis, Roxana Dumitrescu, Yerkin Kitapbayev, Mikhail Zhitlukhin

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