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Seminario CHOPIN
by Matteo Ruggiero 14 Feb '14

14 Feb '14

**************************************************************** STATISTICS SEMINARS @ COLLEGIO CARLO ALBERTO **************************************************************** Venerdi' 21 Febbraio 2014 alle ore 12:00, presso la sala rossa del Collegio Carlo Alberto, Moncalieri (TO), si terra' il seguente seminario: Nicolas CHOPIN (ENSAE, France) SEQUENTIAL QUASI MONTE CARLO Abstract: We develop a new class of algorithms, SQMC (Sequential Quasi Monte Carlo), as a variant of SMC (Sequential Monte Carlo) based on low-discrepancy points. The complexity of SQMC is O(N log N) where N is the number of simulations at each iteration, and its error rate is smaller than the Monte Carlo rate O(N^{-1/2}). The only requirement to implement SQMC is the ability to write the simulation of particle x_t^n given x_{t-1}^n as a deterministic function of x_{t-1}^n and uniform variates. We show that SQMC is amenable to the same extensions as standard SMC, such as forward smoothing, backward smoothing, unbiased likelihood evaluation, and so on. In particular, SQMC may replace SMC within a PMCMC (particle Markov chain Monte Carlo) algorithm. We establish several convergence results. We provide numerical evidence in several difficult scenarios than SQMC significantly outperforms SMC in terms of approximation error. Joint work with Mathieu Gerber. 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 & Collegio Carlo Alberto http://web.econ.unito.it/ruggiero

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[Announce] "Unlocking the value of big data", Special Issue on EJASA-DSS
by stefano iacus 13 Feb '14

13 Feb '14

Call for papers for the Special Issue on "Increasing Innovation Opportunities by Unlocking the Value of Big Data" to be published on the "Electronic Journal of Applied Statistical Analysis: Decisione Support Systems and Services Evalutation" ### Guest Editors: Valentina Ndou,Faculty of Innovation for Engineering, University of Salento (ITA) Mirjeta Beqiri, Gonzaga University, Spokane, WA, (USA) Stefano M. Iacus, Department of Economics, Management and Quantitative Methods, University of Milan (ITA) ### Overview: The advent of new communication technologies and especially the exponential growth of social media web 2.0, from blogs, Facebook and Twitter to LinkedIn and YouTube, has created vast opportunities for firms and managers to get closer to customers, to gain a wealth of information about their behaviors and preferences, as well as to identify new market trends and new opportunities to remain competitive. It is known that firms today operate in the era of Big Data Revolution, overwhelmed with data that are available via web to almost everyone. The content and information that customers create in web 2.0 platforms constitute a valuable asset for firms to directly tap into the customer’s preferences and needs, as the most valuable source for attaining direct and reliable market information. ### Aim: Based on these recent trends, this special issue invites research articles and papers that put forth different approaches, statistical models, and decision making systems able to analyze the available data for gaining insights and creating new knowledge that leads to innovation and creativity. ### Topics: This special issue seeks original contribution on the following topics: 1. Techniques, tools, approaches, and methodologies used for analyzing data and information 2. Statistical Analysis for big data 3. Data and knowledge modelling techniques 4. Stimulating innovation and improving performance through statistical data analysis 5. Value of data for new business models, products, and services 6. Data management as a driver of performance and competitiveness 7. Value co-creation through data and information exchange 8. Transforming the value of data using real time analytics 9. Business optimization techniques through data analysis 10. Decision making process in the big data era 11. Role of statistical models in unlocking the value of web data 12. Real time analytics 13. Privacy, security, and intellectual property issues in the era of big data. ### Submission guidelines: Original research papers will be considered. ### Important Dates: Abstract submission: 20th March, 2014 Review decisions sent to authors: 20th April 2014 Full paper submission: 30th July, 2014 ### Further Information: For further information, please contact: ejasa(a)unisalento.it or visit http://siba-ese.unisalento.it/index.php/ejasa_dss/announcement/view/21

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Young Researchers Meeting on BSDEs, Numerics and Finance
by Marco Fuhrman 13 Feb '14

13 Feb '14

Trasmetto a tutti gli interessati le informazioni rilevanti e il link internet di una conferenza sulle BSDEs (Backward Stochastic Differential Equations) destinata a giovani ricercatori, che si terra' a Bordeaux, 7-9 luglio 2014. Cordialmente, Marco Fuhrman https://indico.math.cnrs.fr/conferenceDisplay.py?confId=199 This international conference is a friendly meeting of young researchers working on: Backward Stochastic Differential Equations, and the related FBSDE, Reflected BSDE, etc... Efficient numerical computation in finance and insurance Robust control, risk management and portfolio optimisation in finance and insurance Nonlinear and Imprecise Probability Location: IMB, Université de Bordeaux, France. Dates and times: Monday 7th July 2014 (14:00) - Wednesday 9th July 2012. Who: Young researchers - broadly students and researchers within 10 years of PhD. Costs: There is no registration fees. For speakers: lunches, refreshments, accommodation at the university residence (7th, 8th, 9th July 2014) and the conference dinner are included. A part of travel costs would be also reimbursed, up to an amount that will be defined after. Non-speaker participants are welcome to apply but we may not be able to guarantee the full accommodation subsidy. Registration: directly on the website by 20 April 2014. Confirmation will be sent to all qualifying participants by the beginning of May. Format: 1/2 hour talks and informal conversations, with an explicitly accessible focus. Remark: If some parts of the website are written in french, you can choose the english version on the top-right corner of the website.

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Avviso di seminario :: Aryasova@DSS (Scienze Statistiche, Sapienza)
by Pierpaolo Brutti 12 Feb '14

12 Feb '14

----------------------------------------------------------------------------- A v v i s o d i S e m i n a r i o ----------------------------------------------------------------------------- Venerdì 14 Febbraio, ore 10am ----------------------------------------------------------------------------- Stanza 34 Dipartimento di Scienze Statistiche Sapienza Università di Roma OLGA ARYASOVA (Inst. of Geophysics, National Academy of Sciences of Ukraine, Ukraine) terrà un seminario dal titolo A REPRESENTATION FOR THE DERIVATIVE WITH RESPECT TO THE INITIAL DATA OF THE SOLUTION OF AN SDE WITH NON-REGULAR DRIFT tutti gli interessati sono invitati a partecipare. ----------------------------------------------------------------------------- Maggiori informazioni sui seminari presso il DSS sono consultabili a quest'indirizzo: http://goo.gl/Y6OQYm Saluti Pierpaolo Brutti --- Summary (* attached *)

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Avviso di seminario :: Porcu@DSS (Scienze Statistiche, Sapienza)
by Pierpaolo Brutti 10 Feb '14

10 Feb '14

----------------------------------------------------------------------------- A v v i s o d i S e m i n a r i o ----------------------------------------------------------------------------- Giovedì 13 Febbraio, ore 15am ----------------------------------------------------------------------------- Stanza 34 Dipartimento di Scienze Statistiche Sapienza Università di Roma EMILIO PORCU (Dep. de Estadística, Universidad de Valparaíso, Chile) terrà un seminario dal titolo ADAPTIVE TAPERS FOR SPACE-TIME GEOSTATISTICS tutti gli interessati sono invitati a partecipare dando magari prima un'occhiata a... http://seismomathics.wordpress.com ----------------------------------------------------------------------------- Maggiori informazioni sui seminari presso il DSS sono consultabili a quest'indirizzo: http://goo.gl/Y6OQYm Saluti Giovanna Jona Lasinio - Pierpaolo Brutti - Fulvio De Santis --- Summary We propose a class of nonseparable space-time compactly supported correlation functions, termed here quasi-tapers, to mean that such correlations can be dynamically compactly supported over space or time. An important feature of the quasi-taper is given by a spatial (temporal) compact support being a decreasing function of the temporal lag (spatial distance), so that the spatial (temporal) compact support becomes smaller when the temporal (spatial) dependence becomes weaker. We propose general classes as well as some examples that generalize the Wendland tapers to the space-time setting. Then a non separable space-time taper with spatial and temporal compact support is obtained as tensor product of quasi-tapers. Our space-time taper includes all the known constructions as special cases and will be shown to have great exibility. Covariance tapering is then explored as an alternative to maximum likelihood when estimating the covariance model of a space-time Gaussian random field in the case of large datasets. The proposed quasi and space-time tapers allows to perform covariance tapering when dealing with data that are densely observed in time (space) but sparse in space (time) or densely observed both in time and space. The statistical and computational properties of the space-time covariance tapering is addressed under increasing domain asymptotics. A simulation study and two real data examples illustrate the statistical and computational performances of the covariance tapering with respect to the maximum likelihood method using the space-time tapers proposed.

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Seminario di Giovanni Puccetti presso Prometeia - Bologna
by Giacomo Scandolo 10 Feb '14

10 Feb '14

Il giorno Giovedì 13 Febbraio 2014, alle ore 14:30 presso la sede di Prometeia (sala grande, primo piano) via G.Marconi 43, Bologna Giovanni PUCCETTI (Università di Firenze) terrà un seminario su: RISK AGGREGATION AND MODEL UNCERTAINTY: SOME MESSAGES FROM THE METHODOLOGICAL FRONT Abstract. We review some of the most recent mathematical achievements in the field of Risk Aggregation and Model Uncertainty and discuss their implications on the current Basel regulatory framework, with particular emphasis on VaR/ES risk measurement. Specific issues that will be handled: - How much superadditive can VaR be? - What are the likely constraints with moving from VaR to ES? - Which kind of dependence is implied by a worst-VaR scenario? - What are the available tools to capture the model uncertainty associated with a joint risk position?

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seminario Stefano Iacus Roma Tre
by Julia Mortera 10 Feb '14

10 Feb '14

Il 19 febbario alle ore 14:30 presso l'aula seminari (III piano) Dipartimento di Economia, Universit? Roma Tre, Via Silvio D'Amico 77 il Prof. Stefano Iacus Dipartimento di Economia, Management e Metodi Quantitativi Universit? degli Studi di Milano terr? il seminario: ***Statistics over Big Data: How to Analyze 80 Millions of Tweets*** Abstract: There are several ways to analyze data coming from digitized texts and there are even more ways to analysis big amount of these data. Analyzing the sentiment expressed on social networks is both about big data and digitized text. But sentiment analysis is not just text mining, i.e. usual data mining applied to text data, because what matters is to capture the meaning of sentences in a corpora of texts whose language evolves in time and space or according to the age, the background of the writers, etc. We will discuss the most recent techniques of sentiment analysis available in the literature along with some new ideas and present some applications to the analysis of 80 millions of italian tweets to happyness and economics.

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Seminar and Mini-course of Emmanuel Bacry at the Scuola Normale Superiore di Pisa
by Fabrizio Lillo 07 Feb '14

07 Feb '14

Emmanuel Bacry (CMAP, Ecole Polytechnique, France) will give a seminar at the Scuola Normale di Pisa on Thursday February 27 in Aula Bianchi at 1 pm The title and abstract are Hawkes process and applications Hawkes processes are point self-exciting point processes particularly well suited for applications. Introduced in the 70s, that have been used in very various domaines such as high-frequency financial time-series modeling or viral diffusion in social networks. After describing how they are defined and their main properties, we shall discuss some problems linked to parametric estimations (in high dimensions) as well as non parametric estimations. We will present several applications. Moreover he will give a mini-course on Modeling and analysis of high frequency financial time-series The agenda is attached below. Interested people are invited to participate. For more information, contact Fabrizio Lillo (fabrizio.lillo(a)sns.it) &&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&& Tuesday February 25, Aula Fermi, 9.00-11.00 1- Introduction to different market and asset types - Which financial time-series for statistical analysis ? Thursday February 27, Aula Bianchi, 14.00-16.00 2- Orderbooks dynamics - Qualitative description - Some statistical elements of order books - Transaction costs - Price impact - Response function Wednesday March 5, Aula Bianchi, 14.00-16.00 3- Tick-by tick financial time-series - trading time versus physical time - ACD models - Microstructure noise Thursday March 6, Aula Bianchi, 14.00-16.00 4- Hawkes processes based tick-by-tick modeling - Microstructure noise modeling - Trading flow modeling - Response and Impact modeling ------------------------------------------------------------ Fabrizio Lillo Scuola Normale Superiore di Pisa, Dipartimento di Fisica, Universita' di Palermo & Santa Fe Institute, U.S.A. Piazza dei Cavalieri 7 56126 Pisa ITALY phone: +39 050509159 web: https://sites.google.com/site/fabriziolillo9670/home

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I: postdoc position available
by Massimo Campanino 07 Feb '14

07 Feb '14

________________________________________ Da: Aernout van enter [avanenter(a)gmail.com] Inviato: giovedì 6 febbraio 2014 18.24 A: aldo(a)mat.ufmg.br; Vladas Sidoravicius; gentz(a)math.uni-bielefeld.de; gantert(a)ma.tum.de; maspm(a)bath.ac.uk; spohn(a)ma.tum.de; Massimo Campanino; Jacek Miekisz; Charles Newman; Gordon Slade Oggetto: Re: postdoc position available [https://mail.google.com/mail/u/0/images/cleardot.gif] Announcement: postdoc position Groningen A one - year postdoc position is available, funded by NWO, to work on the topic of ``hidden symmetries, new and dual models of interacting particle systems.'' The project has a targeted starting date of 1 september 2014. The postdoc will work at Rijksuniversiteit Groningen and will work with the main investigators investigators A.C.D. van Enter and F. Redig (Delft University). Besides he will have the opportunity to collaborate within an international network related to this and comparable projects, situated in Modena ( C. Giardina, G. Carinci) and Warwick ( S. Grosskinsky). More information and details about the project and the position can be obtained from F. Redig (http://dutiosb.twi.tudelft.nl/~redig<http://dutiosb.twi.tudelft.nl/%7Eredig>)and A.C.D. van Enter (http://www.math.rug.nl/dsmp/People/AernoutvanEnter) Interested candidates are asked to send a letter of motivation and CV to F. Redig (f.h.j.redig(a)tudelft.nl<mailto:f.h.j.redig@tudelft.nl>) and A.C.D. van Enter (avanenter(a)gmail.com<mailto:avanenter@gmail.com>) ___________________ Prof.dr A.C.D. van Enter University of Groningen Department of Mathematics P.O. Box 800 9700 AV Groningen The Netherlands Telephone: +31 50 3633939<tel:%2B31%2050%203633939> (secretary) +31 50 3634967<tel:%2B31%2050%203634967> (extension) +31 50 3633800<tel:%2B31%2050%203633800> (telefax) +31 50 5266329<tel:%2B31%2050%205266329> (home) Email: aenter(a)phys.rug.nl<mailto:aenter@phys.rug.nl> URL: http://www.math.rug.nl/~aente<http://www.math.rug.nl/%7Eaenter>

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Workshop MathStatNeuro 2-4 July Copenhagen
by Massimiliano Tamborrino 05 Feb '14

05 Feb '14

Dear all, Rune Berg, Susanne Ditlevsen and I organize a 3-days workshop in Copenhagen, 2nd-4th of July, "Mathematical Modeling and Statistical Analysis in Neuroscience", funded by the Dynamical Systems Interdisciplinary Network, University of Copenhagen, www.dsin.ku.dk. The idea is to bring together theoretical, experimental and computational researchers who are working on various topics in neuroscience. There is no conference fee and we hope to offer free lunch for all registered participants. Conference website homepage is: http://www.math.ku.dk/english/research/conferences/mathstatneuro2014 If you would like to attend, please register within the 15th May 2014 at: http://www.math.ku.dk/english/research/conferences/mathstatneuro2014/regist… We hope to welcome you in Copenhagen! Best wishes, Susanne, Rune and Massimiliano -- --------------------------------- Dr. Massimiliano Tamborrino Postdoctoral fellow Department of Mathematical Sciences University of Copenhagen email: mt(a)math.ku.dk URL: http://www.math.ku.dk/~mt/ Universitetsparken 5 DK-2100 Kobenhavn Ø, Denmark -----------------------------------------

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