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Seminar announcement - Petter Kolm (April 28 at 4 pm)
by Fabrizio Lillo 25 Apr '21

25 Apr '21

*Wednesday April 28 at 4pm (CEST):* Petter Kolm (NYU, Courant Institute) *Title*: Feature Selection in Jump Models *Abstract*: Jump models switch infrequently between states to fit a sequence of data while taking the ordering of the data into account. In this talk, we propose a new framework for joint feature selection, parameter and state-sequence estimation in jump models. Feature selection is necessary in high-dimensional settings where the number of features is large compared to the number of observations and the underlying states differ only with respect to a subset of the features. We develop and implement a coordinate descent algorithm that alternates between selecting the features and estimating the model parameters and state sequence, which scales to large data sets with large numbers of (noisy) features. We demonstrate the usefulness of the proposed framework by comparing it with a number of other methods on both simulated and real data in the form of financial returns, protein sequences, and text. The resulting sparse jump model outperforms all other methods considered and is remarkably robust to noise. This is joint work with Erik Lindstrom and Peter Nystrup The link for joining the meeting is: https://teams.microsoft.com/l/meetup-join/19%3ameeting_NjVmYWI3OTMtZWZkYy00… Best regards Fabrizio Lillo ---------------------------------------- Fabrizio Lillo Dipartimento di Matematica, Università di Bologna Scuola Normale Superiore, Pisa ITALY Personal website: fabriziolillo.wordpress.com University website: www.unibo.it/sitoweb/fabrizio.lillo <http://fabriziolillo.wordpress.com/> phone: +39 050509159

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Seminar announcement
by Marco Scarsini 23 Apr '21

23 Apr '21

Thursday, 29 April, 17:00 CEST *Carri Chan,* Columbia University Prediction-Driven Surge Planning with Applications in the Emergency Department <http://mailsender.luiss.it/lists/lt.php?id=cRpQBwwLSAULAAdOVgFdBQs> Optimizing emergency department (ED) nurse staffing decisions to balance the quality of service and staffing cost can be extremely challenging, especially when there is a high level of uncertainty in patient-demand. Increasing data availability and continuing advancements in predictive analytics provide an opportunity to mitigate demand-rate uncertainty by utilizing demand forecasts. In this work, we study a two-stage prediction framework that is synchronized with the base (made months in advance) and surge (made nearly real-time) staffing decisions in the ED. We quantify the benefit of the more expensive surge staffing. We also propose a near-optimal two-stage staffing policy that is straightforward to interpret and implement. Lastly, we develop a unified framework that combines parameter estimation, real-time demand forecasts, and staffing in the ED. High fidelity ED simulation experiments demonstrate that the proposed framework can reduce staffing costs by 8% – 17% while guaranteeing timely access to care. Joint work with Jing Dong and Yue Hu. Discussants: Vahid Sarhangian and Julien Grand-Clément This is the link to the Virtual Room <http://mailsender.luiss.it/lists/lt.php?id=cRpQAAYBSAULAAdOVgFdBQs>. If you want to receive the password to access the virtual room, please fill out this form <https://docs.google.com/forms/d/e/1FAIpQLSeDxM-M5ogG43elgjC-lNCp0BDhISiZHG0…> (If you filled it out in the past, this is not necessary). The schedule of the upcoming seminars can be found here <https://economiaefinanza.luiss.it/en/seminars/2020-2021-seminars>. ******************************************************* Marco Scarsini Dipartimento di Economia e Finanza Luiss Viale Romania 32 00197 Roma, ITALY URL: http://docenti.luiss.it/scarsini/

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Webinar "Near-maxima and near-records", by F. Javier López Lorente
by Antonio DI CRESCENZO 23 Apr '21

23 Apr '21

---------- Forwarded message --------- Dear colleagues, We kindly invite you to attend the SPA Webinar *"Near-maxima and near-records"*, by F. Javier López Lorente (Universidad de Zaragoza, Spain), on April 29, 2021, Thursday, at 16:30 p.m. (UTC+2). You may read the abstract at: blogs.mat.ucm.es/presa/our-webinar If you wish to attend this SPA Webinar, please send an email to the organizers (agcorral(a)ucm.es). You will receive an email with the link to access the seminar a few hours before the seminar starts. The SPA Webinar Series is organized by the Working Group on *"Stochastic Processes and their Applications"* of the Spanish Society for Statistics and Operations Research. With best regards, Miguel González Velasco & Antonio Gómez-Corral *Coordinators of the Working Group* -- *Antonio Gómez-Corral* Facultad de Ciencias Matemáticas Plaza de Ciencias 3 Universidad Complutense de Madrid 28040 Madrid Teléfono: +34 91 394 44 28 E-mail: agcorral(a)ucm.es Web page: blogs.mat.ucm.es/agomez-corral Las matemáticas de la pandemia (CSIC-Catarata, 2020): blogs.mat.ucm.es/agomez-corral/2020/11/07/las-matematicas-de-la-pandemia/ Antes de imprimir este correo piense si es necesario: el medio ambiente es cosa de todos. Before printing this mail please consider whether it is really necessary: the environment is a concern for us all.

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Webinar in Statistics MATTHIAS LOFFLER
by Pierpaolo De Blasi 23 Apr '21

23 Apr '21

WEBINARS IN STATISTICS @ COLLEGIO CARLO ALBERTO <https://www.carloalberto.org/events/category/seminars/seminars-in-statistic…> Venerdi 30 Aprile 2021, alle ore 12.00, si terrà il seguente webinar: ------------------------------------------------ Speaker: *Matthias Loffler *(ETH Zurich) Title: *Optimality of Spectral Clustering in the Gaussian Mixture Model* Zoom link: https://us02web.zoom.us/j/81943504316?pwd=anlwTXpXSkU4R1ZsMjMxVEo5NHcwQT09 Meeting ID: 819 4350 4316 Passcode: 355115 Abstract: Spectral clustering is one of the most popular algorithms to group high dimensional data. It is easy to implement and computationally efficient. Despite its popularity and successful applications, its theoretical properties have not been fully understood. We show that spectral clustering is minimax optimal in the Gaussian Mixture Model with isotropic covariance matrix, when the number of clusters is fixed and the signal-to-noise ratio is large enough. Spectral gap conditions are widely assumed in the literature to analyze spectral clustering. On the contrary, we show that these conditions are not needed. ------------------------------------------------ Il webinar è organizzato dalla "de Castro" Statistics Initiative www.carloalberto.org/stats Cordiali saluti, Pierpaolo De Blasi --- University of Torino & Collegio Carlo Alberto carloalberto.org/pdeblasi <https://sites.google.com/a/carloalberto.org/pdeblasi/>

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Post-doc position available at the University of Oslo, Norway. Deadline approaching!
by Valeria Vitelli 22 Apr '21

22 Apr '21

*A three-years postdoc position in Biostatistics is offered at the Oslo Centre for Biostatistics and Epidemiology (OCBE), University of Oslo, Norway. * The position is funded under the* SCIENTIA FELLOWS* program, a transnational research fellowship programme in the field of Health Life Sciences at the University of Oslo, funded by the EU Horizon 2020 under the Maria Skłodowska-Curie scheme. *More information available here:* https://www.med.uio.no/imb/english/research/groups/statistics-high-dimensio… *Hosts: *Valeria Vitelli ( https://www.med.uio.no/imb/english/people/aca/valeriv/) and David Swanson ( https://sojourningnorth.github.io/) *Deadline for submission: May 11th, 2021* *Call, detailed information and how to apply:* (thematic area: "biostatistics") https://www.med.uio.no/english/research/scientia-fellows/apply/ *If you are interested in the position, please contact the hosts above as soon as possible! *In order to apply for the position, you have to submit a research proposal (and other documents as specified in the call) by May 11th, 2021. The position will be at the Oslo Centre for Biostatistics and Epidemiology (OCBE), Faculty of Medicine, University of Oslo ( https://www.med.uio.no/imb/english/research/centres/ocbe/). *Salary: 526 000 NOK/year (roughly 52K EUR/year)* *Eligibility:* - You possess a PhD degree (at the latest by 1 July 2021) in statistics, biostatistics, mathematics, computer science or other related disciplines with a documented competence in statistics, biostatistics or mathematics. - You have not been resident in Norway for more than 12 months in the last 3 years. -- Valeria Vitelli Oslo Center for Biostatistics and Epidemiology, Department of Biostatistics, University of Oslo, Norway mailto: valeria.vitelli(a)medisin.uio.no

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Summer School - Stochastic Models and Complex Systems
by Barbara Martinucci 22 Apr '21

22 Apr '21

Dear All, We are glad to announce the forthcoming Summer School, entitled *"Stochastic Models and Complex Systems"*, that will be held online in the period June 10th - July 7th, 2021. The Summer School is open to PhD students, postdoc and young researchers interested in the treated topics. It will feature mini-courses of plenary speakers, exercise sessions and students' talks. *Plenary courses *include: - *Enrico Scalas* (University of Sussex) "*A gentle introduction to combinatorial stochastic processes (with applications to Physics, Finance and Economics)*", 16 hours; - *Yuliia Mishura* (Taras Shevchenko National University of Kyiv) "*Statistics of fractional models*", 8 hours; - *Jorge Navarro* (University of Murcia) "*Selected Topics on Distorted models and applications*", 6 hours. An outline of the event, including the themes covered, is already available on the website http://dipmat2.unisa.it/iniziative/smocs2020/School.html The students willing to apply for the Summer School are invited to fill the registration form available on the website. The participation is free but the registration is mandatory. Only the first 50 registration will be admitted. For any question, send an email to: smocs2021(a)gmail.com Do not hesitate to CIRCULATE this announcement to your colleagues and students. Best regards, the Organizing Committee

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2nd Spring Colloquium on Probability and Finance
by Claudio Fontana 22 Apr '21

22 Apr '21

Dear all, We would like to bring to your attention the following virtual workshop: /2ND SPRING COLLOQUIUM ON PROBABILITY AND FINANCE - /29 APRIL 2021, 9.00 - 13.00, ONLINE University of Padova, Department of Mathematics "Tullio Levi-Civita" The second edition of the Spring Colloquium on Probability and Finance will bring together researchers working in stochastic analysis and mathematical finance. The workshop will feature five invited talks and attendance is open. To attend the Colloquium, please register by sending an e-mail to the organisers (Giorgia Callegaro and Claudio Fontana). _SPEAKERS_: • René AID (Paris Dauphine Universty, FR) • Luciano CAMPI (University of Milan, IT) • Alessandro GNOATTO (University of Verona, IT) • Antoine JACQUIER (Imperial College London, UK) • Barbara PACCHIAROTTI (University of Rome "Tor Vergata", IT) Best regards, Giorgia Callegaro and Claudio Fontana

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Pisa Online Seminars - Constanza Rojas-Molina (Tuesday, April 27 at 16:00)
by Giacomo Filippo Di Gesu 21 Apr '21

21 Apr '21

Dear colleagues, I would like to invite you to the following online seminar organized by the Probability group of the University of Pisa. The talk will be accessible under the link Click here to join<https://teams.microsoft.com/l/meetup-join/19:af3d635091e049579e555a84219ab3…"Tid":"c7456b31-a220-47f5-be52-473828670aa1","Oid":"dfd1e5f6-331d-43e0-a180-4bb6ce727fb7"}> Best regards, Giacomo Tuesday, April 27, 16:00 Speaker: Constanza Rojas-Molina (CY Cergy Paris Université) Title: (Fractional) random Schrödinger operators, integrated density of states and localization Abstract: We consider the continuous Schrödinger operator - d^2/d^x^2 + B’(x) on the interval [0,L] where the potential B’ is a white noise. We study the entire spectrum of this operator in the large L limit. We prove the joint convergence of the eigenvalues and of the eigenvectors and describe the limiting shape of the eigenvectors for all energies. When the energy is much smaller than L, we find that we are in the localized phase and the eigenvalues are distributed as a Poisson point process. The transition towards delocalization holds for large eigenvalues of order L. In this regime, we show the convergence at the level of operators. The limiting operator in the delocalized phase is acting on R^2-valued functions and is of the form ``J \partial_t + 2*2 noise matrix'' (where J is the matrix ((0, -1)(1, 0))), a form appearing as a conjecture by Edelman Sutton (2006) for limiting random matrices. Joint works with Cyril Labbé. ************************ Giacomo Di Gesù Dipartimento di Matematica Università di Pisa Largo Bruno Pontecorvo 5 56127 - Pisa, Italy giacomo.digesu(a)unipi.it<mailto:giacomo.digesu@unipi.it> https://sites.google.com/site/giacomodigesu/

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(PMS)^2 online talk: Zdzislaw Brzezniak, Monday April 26 at 17:30
by Mario Maurelli 21 Apr '21

21 Apr '21

Dear colleagues, We are happy to announce the following online talk: Speaker: *Zdzislaw Brzezniak* (University of York, UK) Title: *The stochastic Strichartz estimates and stochastic nonlinear Schrödinger equations driven by Levy noise* Date and time: *Monday April 26, 17:30-18:30 (Rome time zone)* Abstract: see below Zoom link: https://us02web.zoom.us/j/87131794820?pwd=R3l0VEtpZXNzUmQ1bnlnbWhBUm5XQT09 Meeting ID: 871 3179 4820 Passcode: 5yFGwK This talk is the first 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. The series will run approximately every fortnight and, for the moment, will be held online. 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) Abstract: We establish a new version of the stochastic Strichartz estimate for the stochastic convolution driven by jump noise which we apply to the stochastic nonlinear Schrodinger equation with nonlinear multiplicative jump noise in the Marcus canonical form. With the help of the deterministic Strichartz estimates, we prove the existence and uniqueness of a global solution to stochastic nonlinear Schrodinger equation in $L^2(R^n)$ with either focusing or defocusing nonlinearity in the full subcritical range of exponents as in the deterministic case. This talk will be based on a joint paper with Wei Liu and Jiahui Zhu.

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Seminar Pierre Alquier @Bocconi - April 22
by Giacomo Zanella 21 Apr '21

21 Apr '21

A reminder of the following BIDSA webinar (link <https://www.bidsa.unibocconi.eu/wps/wcm/connect/site/bidsa/home/news_events…> ): Date: Thursday, April 22, h14:00 (Italy time) Speaker: Pierre Alquier (RIKEN) Title: Robust Estimation via M.M.D. Minimization Abstract: In this talk, I will study the properties of parametric estimators based on the Maximum Mean Discrepancy (MMD) defined by Briol et al. (2019). In a first time, I will show that these estimators are universal in the i.i.d setting: even in case of misspecification, they converge to the best approximation of the distribution of the data in the model, without ANY assumption on this model. This leads to very strong robustness properties. In a second time,I will show that these results remain valid when the data is not independent, but satisfy instead a weak-dependence condition. This condition is based on a new dependence coefficient, which is itself defined thanks to the MMD. I will show through examples that this new notion of dependence is actually quite general. Reference: This talk is based on the following papers and softwares, with Badr-Eddine Chérief Abdellatif (Oxford University), Mathieu Gerber(University of Bristol), Jean-David Fermanian (ENSAE Paris) and Alexis Derumigny (University of Twente): http://arxiv.org/abs/1912.05737 http://proceedings.mlr.press/v118/cherief-abdellatif20a.html http://arxiv.org/abs/2006.00840 https://arxiv.org/abs/2010.00408 https://cran.r-project.org/web/packages/MMDCopula/ The webinar will be on zoom at: https://zoom.us/j/95795747882 Meeting ID: 957 9574 7882 Passcode: 025765 Kind regards, Giacomo Zanella

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