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(senza oggetto)
by Fabio Martinelli 04 Dec '16

04 Dec '16

Il Prof. A. Smith dell'universita' di Ottawa terra' tre lezioni nell'ambito del dottorato in matematica presso il Dip. di Matematica e Fisica di Roma Tre con il seguente programma: *MIXING OF MARKOV CHAINS ON MANIFOLDS* Martedi 6 Dicembre ore 11:00-13:00 aula 311 *Mixing Properties of Hamiltonian Monte Carlo* Abstract:* Hamiltonian Monte Carlo (HMC) and its variants are extremely popular Markov chain Monte Carlo algorithms in statistical computing. In practice, they seem to outperform classical algorithms such as the Gibbs sampler and the Metropolis-Hastings algorithm. Unfortunately, the characteristic long moves made by HMC also make it difficult to analyze. I will survey some existing results on HMC and competitor algorithms, including some recent results of myself and Mangoubi, and present open problems.* Mercoledi 7 Dicembre ore 14:30-16:30 aula 311 *Convex Sets, Conductance and Curvature.* Abstract: Geometric random walks are popular tools for sampling from the interior or boundary of convex sets. I will introduce some popular geometric random walks and describe the mathematical techniques developed by Dieker, Kannan, Lovasz, Vempala and others to analyze them. I will then describe how some recent work takes advantage of ideas from geometry and convex optimization to propose and analyze algorithms that can have improved performance. Martedi 13 Dicembre ore 11:00-13:00 aula 311 *Kac's Walks and Couplings.* Abstract: Kac's walks on the sphere and on the special orthogonal group. introduced in 1953 and 1970, have long histories in the statistical physics and computational statistics literatures. I will describe the history of these walks and review some of the many results on the mixing properties of these processes. I then present some recent work of myself and Pillai, which uses connections to random matrix theory to obtain substantially improved bounds on the mixing times of these two walks. -- Fabio Martinelli Department of Mathematics and Physics Roma Tre University Lg. San Murialdo 1, 00146 Roma Italy tel +39 06 57338039 fax +39 06 57338039

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Mini corso di A. Smith a Roma Tre
by Pietro Caputo 04 Dec '16

04 Dec '16

Il Prof. A. Smith dell'universita' di Ottawa terra' tre lezioni nell'ambito del dottorato in matematica presso il Dip. di Matematica e Fisica di Roma Tre con il seguente programma: *MIXING OF MARKOV CHAINS ON MANIFOLDS* Martedi 6 Dicembre ore 11:00-13:00 aula 311 *Mixing Properties of Hamiltonian Monte Carlo* Abstract:* Hamiltonian Monte Carlo (HMC) and its variants are extremely popular Markov chain Monte Carlo algorithms in statistical computing. In practice, they seem to outperform classical algorithms such as the Gibbs sampler and the Metropolis-Hastings algorithm. Unfortunately, the characteristic long moves made by HMC also make it difficult to analyze. I will survey some existing results on HMC and competitor algorithms, including some recent results of myself and Mangoubi, and present open problems.* Mercoledi 7 Dicembre ore 14:30-16:30 aula 311 *Convex Sets, Conductance and Curvature.* Abstract: Geometric random walks are popular tools for sampling from the interior or boundary of convex sets. I will introduce some popular geometric random walks and describe the mathematical techniques developed by Dieker, Kannan, Lovasz, Vempala and others to analyze them. I will then describe how some recent work takes advantage of ideas from geometry and convex optimization to propose and analyze algorithms that can have improved performance. Martedi 13 Dicembre ore 11:00-13:00 aula 311 *Kac's Walks and Couplings.* Abstract: Kac's walks on the sphere and on the special orthogonal group. introduced in 1953 and 1970, have long histories in the statistical physics and computational statistics literatures. I will describe the history of these walks and review some of the many results on the mixing properties of these processes. I then present some recent work of myself and Pillai, which uses connections to random matrix theory to obtain substantially improved bounds on the mixing times of these two walks. -- Fabio Martinelli Department of Mathematics and Physics Roma Tre University Lg. San Murialdo 1, 00146 Roma Italy tel +39 06 57338039 <+39%2006%205733%208039> fax +39 06 57338039 <+39%2006%205733%208039>

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Seminario SAMUEL HERRMANN @ UniTo
by Cristina Zucca 02 Dec '16

02 Dec '16

********************************************************************* SEMINARI DI PROBABILITA' E STATISTICA MATEMATICA DIPARTIMENTO DI MATEMATICA "G. PEANO" UNIVERSITA' DEGLI STUDI DI TORINO ********************************************************************* Martedì 6 dicembre alle ore 12:00 in aula C presso il Dipartimento di Matematica "G. Peano" dell'Università degli Studi di Torino, Via Carlo Alberto 10, Il Prof. SAMUEL HERRMANN (Université de Bourgogne) terrà un seminario dal titolo Initial-Boundary Value Problem for the heat equation - A stochastic algorithm Abstract: The Initial-Boundary Value Problem for the heat equation is solved using a new algorithm based on a random walk on heat balls. Even if it represents a sophisticated generalisation of the Walk on Spheres (WoS) algorithm introduced to solve the Dirichlet problem for Laplace's equation, its implementation is rather easy. The definition of the random walk is based on a new mean value formula for the heat equation. The convergence results and different numerical examples permit to emphasize the efficiency and accuracy of the algorithm. Tutti gli interessati sono invitati a partecipare. -- Dr. Cristina Zucca Department of Mathematics University of Torino Via Carlo Alberto 10 10123 Torino, Italy tel: +39-011-6702850 fax: +39-011-6702878

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Bando RTDA 13/D1, Sapienza Università di ROMA
by Brunero Liseo 28 Nov '16

28 Nov '16

CON PREGHIERA DI DIFFUSIONE Si comunica che presso il dip. di Metodi e Modelli per l’Economia, il Territorio e la Finanza, Sapienza Università di Roma, è indetta una procedura di valutazione a 1 posto di ricercatore a tempo determinato di tipo A per il settore scientifico concorsuale 13/D1 Statistica (ssd SECS-S/01). Data di scadenza bando: 27-12-2016 Link: http://www.memotef.uniroma1.it/sites/dipartimento/files/Bando_RTD_%20A_SECS… Non esiste una traduzione in inglese del bando; per informazioni sommarie si veda http://bandi.miur.it/jobs.php/public/job/id_job/45583 Cordialmente Brunero LISEO -- ============================================ Brunero Liseo *Dip. di metodi e modelli per il territorio, l'economia e la finanza * *Sapienza Università di Roma* *Viale Castro Laurenziano, 9 Roma I-00161 *Tel. +39 06 49766973 Fax +39 06 4957606 *http://www.memotef.uniroma1.it/users/liseo-brunero <http://www.memotef.uniroma1.it/users/liseo-brunero>* =============================================

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Two postdocs jobs, Barcelona : deadline: January 8th (fwd)
by Tiziano Vargiolu 27 Nov '16

27 Nov '16

The Barcelona Graduate School of Mathematics (BGSMath) opens a call for two postdoctoral positions in the areas: 1. Algebra, Combinatorics, Geometry and/or Logic. 2. Analysis, Dynamical Systems, and/or Probability Theory. Succesful applicants will join the BGSMath research group of their choice in one of the five BGSMath institutions in Barcelona: Universitat Aut?noma de Barcelona, Universitat de Barcelona, Universitat Polit?cnica de Catalaunya, Universitat Pompeu Fabra or Centre de Recerca Matem?tica. We summarize the details of the call which can be found at http://bgsmath.cat/bgsmath-postdoctoral-call-2017-2019/ - Two year contracts. - Annual gross salary of 26.250?, plus 2000? mobility (to be provided by the research group) - Requirements: To hold a Ph.D. degree at the time of application and at least two years of doctoral or postdoctoral experience outside of Catalonia. - Deadline: January 8th

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HCM Winter School "Recent developments in singular stochastic PDEs"
by Francesco Caravenna 26 Nov '16

26 Nov '16

Ricevo e inoltro. > Da: Massimiliano Gubinelli <gubinelli(a)iam.uni-bonn.de> > Oggetto: HCM Winter School "Recent developments in singular stochastic PDEs" > > Dear colleagues, > we are organising a specialised Hausdorff Winter School entitled > > Recent developments in singular stochastic PDEs > > to be held at the > > Hausdorff Institute for Mathematics at the University of Bonn > > from 20 - 24 February 2016. > > http://www.hcm.uni-bonn.de/stochastic-pdes-2017/ > > The aim of the school is to introduce motivated graduate students and postdocs to > some of the recent developments in the theory of singular stochastic PDE. > > Following Hairer’s work on regularity structures (for which he was awarded the 2014 > fields medal) interest in this field has literally exploded over the last years and a large > number of results were obtained within a short time. Among these are universality > results for scaling limits of particle models from statistical physics, links to perturbative > quantum field theory and to the regularity theory for PDE. In this school we aim to introduce > the participants to these recent developments. There will be four short courses taught by > > Ajay Chandra (Warwick) > Nicolas Perkowski (Berlin) > Hendrik Weber (Warwick) > Lorenzo Zambotti (Paris) > > In addition to these courses, a key part of the programme will be a number of interactive > exercise sessions in which the participants will have the opportunity to get hands on > experience of working with these equations. > > Online registration for the school is now open at > > https://www.hcm.uni-bonn.de/stochastic-pdes-2017/ > > Registration closes on January 15, 2017. Precedence will be given to applications submitted before December 15, 2016. There will be limited funding to support participants travel and accommodation. > > > Hope to see you soon in Bonn, > > Massimiliano Gubinelli > Hendrik Weber >

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Seminari JARA and BRODERICK
by Matteo Ruggiero 25 Nov '16

25 Nov '16

******************************************************************* STATISTICS SEMINARS @ COLLEGIO CARLO ALBERTO ******************************************************************* Venerdi 2 Dicembre 2016, presso l’Aula Rossa del Collegio Carlo Alberto, Moncalieri (TO), si terranno i seguenti seminari: ----- h 11.00 Alejandro JARA (Pontificia Universidad Católica de Chile) BAYESIAN NONPARAMETRIC APPROACHES FOR THE ANALYSIS OF COMPOSITIONAL DATA BASED ON BERNSTEIN POLYNOMIALS ----- h 12.00 Tamara BRODERICK (MIT) FAST QUANTIFICATION OF UNCERTAINTY AND ROBUSTNESS WITH VARIATIONAL BAYES ----- Gli abstract delle relazioni sono disponibili alla pagina http://www.carloalberto.org/events/seminars/statistics/ Tutti gli interessati sono invitati a partecipare. Il seminario e' organizzato dalla "de Castro" Statistics Initiative (http://www.carloalberto.org/stats) in collaborazione con il Collegio Carlo Alberto. Cordiali saluti, Matteo Ruggiero --- Matteo Ruggiero University of Torino and Collegio Carlo Alberto www.matteoruggiero.it

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PhD positions at the Institute of Science and Technology Austria (IST Austria)
by Giovanni Zanco 24 Nov '16

24 Nov '16

Dear Colleague, The *Institute of Science and Technology Austria (IST Austria)* is looking for highly qualified candidates to apply for our ISTScholar PhD program. We offer *fully-funded PhD positions* in the natural and mathematical sciences in a world-class research environment on the outskirts of Vienna. The research topics that might interest students in your department include: *Mathematics* - Nick Barton: Mathematical Models of Evolution - Herbert Edelsbrunner: Algorithms, Computational Geometry and Topology - Lászlá Erdős: Mathematical Physics, Probability - Julian Fischer: Theory of Partial Differential Equations, Applied and Numerical Analysis - Tamas Hausel: Geometry and its Interfaces - Jan Maas: Stochastic Analysis, Optimal Transport - Robert Seiringer: Quantum Statistical Mechanics, Mathematical Physics - Uli Wagner: Discrete and Computational Geometry and Topology Our PhD program is characterized by innovative training with a special focus on interdisciplinarity, close mentoring by outstanding faculty within small research groups, and access to first-rate facilities. Students spend the first year completing coursework and rotations before choosing a thesis group and passing the qualifying exam. Our PhD graduates have gone on to top positions in academia and industry all over the world. Students with a *bachelor’s* *or* *master’s* degree in a relevant field are encouraged to apply. We offer *internationally competitive salaries* co-funded by an EU Marie Sklodowska-Curie grant, full health benefits, and subsidized on-campus housing in the first year. For more information about the ISTScholar PhD program and application process, as well as faculty profiles, please visit our website at http://phd.ist.ac.at. *The deadline for PhD applications is January 8th 2017 for a start date in September 2017*. Yours sincerely, *Hania Köver* Head of the Graduate School Office *Giovanni Zanco* Stochastic Analysis Group Institute of Science and Technology Austria gradschool(a)ist.ac.at

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Annuncio seminario
by Piccioni, Mauro 24 Nov '16

24 Nov '16

*Dipartimento di Matematica, Sapienza Università di Roma * *Martedì 29 novembre* * Ore 14:00, Aula di Consiglio* * Seminario di Probabilità e Statistica Matematica* *Pietro Caputo, Dipartimento di Matematica, Università di Roma Tre* *Titolo: Random walk on sparse random directed graphs* *Abstract: **A random walk on a finite graph exhibits cutoff if its distance from stationarity remains close to the initial value for a certain number of iterations and then abruptly drops to near zero on a much shorter time scale. Originally discovered in the context of card shuffling by Aldous and Diaconis in 1986, this remarkable phenomenon is now rigorously established for many reversible chains. Here we consider the non-reversible case of random walks on sparse random directed graphs, for which even the stationary distribution is far from being understood. We establish the cutoff phenomenon, determine its time window and prove that the cutoff profile approaches a universal gaussian shape. Moreover, we determine an explicit recursive equation characterizing the stationary distribution. This talk is based on joint work with Charles Bordenave and Justin Salez.* *Tutti gli interessati sono invitati a partecipare.* *Per qualsiasi richiesta di informazioni rivolgersi a **piccioni(a)mat.uniroma1.it <piccioni(a)mat.uniroma1.it>.*

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Annuncio di seminario
by Piccioni, Mauro 24 Nov '16

24 Nov '16

*Dipartimento di Matematica, Sapienza Università di Roma * *Martedì 29 novembre* * Ore 14:00, Aula di Consiglio* * Seminario di Probabilità e Statistica Matematica* *Pietro Caputo, Dipartimento di Matematica, Università di Roma Tre* *Titolo: Random walk on sparse random directed graphs* *Abstract: **A random walk on a finite graph exhibits cutoff if its distance from stationarity remains close to the initial value for a certain number of iterations and then abruptly drops to near zero on a much shorter time scale. Originally discovered in the context of card shuffling by Aldous and Diaconis in 1986, this remarkable phenomenon is now rigorously established for many reversible chains. Here we consider the non-reversible case of random walks on sparse random directed graphs, for which even the stationary distribution is far from being understood. We establish the cutoff phenomenon, determine its time window and prove that the cutoff profile approaches a universal gaussian shape. Moreover, we determine an explicit recursive equation characterizing the stationary distribution. This talk is based on joint work with Charles Bordenave and Justin Salez.* *Tutti gli interessati sono invitati a partecipare.* *Per qualsiasi richiesta di informazione scrivere a piccioni(a)mat.uniroma1.it*

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