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Second Italian Meeting on Probability and Mathematical Statistics
by Antonio DI CRESCENZO 12 Jun '19

12 Jun '19

Dear Colleagues, we recall that the *Second Italian Meeting on Probability and Mathematical Statistics* is forthcoming (Vietri sul Mare (SA), Italy, June 17th - 20th, 2019). See all details at the conference web site: http://www.salerno2019.dipmat.unisa.it Looking forward meeting you soon in Vietri sul Mare. *The Scientific Committee* Claudia Ceci, Paolo Dai Pra, Antonio Di Crescenzo, Franco Fagnola, Franco Flandoli, Antonio Lijoi, Andrea Pascucci, Franco Pellerey, Laura Sacerdote *The Local Organizing Committee* Giacomo Ascione, Aniello Buonocore, Camilla Calì, Luigia Caputo, Antonio Di Crescenzo, Maria Longobardi, Barbara Martinucci, Alessandra Meoli, Luca Paolillo, Paola Paraggio, Enrica Pirozzi, Fabio Travaglino

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Seminario: Samuele Stivanello, Ecology of human activities
by Antonio Pievatolo 11 Jun '19

11 Jun '19

Lunedi' 17 giugno alle 14:45, presso il CNR-IMATI, in via A. Corti, 12, Milano, Aula Pentagonale edificio Bassini II piano, si terrà il seguente seminario: Samuele Stivanello, Dipartimento di Matematica, Universita' di Padova Title: Ecology of human activities Abstract: One of the most studied macro-ecological pattern is the Relative Species Abundance (RSA), describing the distribution of the population among species. Various natural ecosystems share a common shape of the empirical RSA and through years ecologists have used several recipes - some of them are rule of thumb prescriptions - to determine global RSA features from local information. Recently our group has developed a rigorous statistical framework able to predict global scale biodiversity from scattered local plots ([2], [3]). Such a framework is derived from a simple mathematical model informed by basic biological assumptions. In this talk we illustrate how to adapt/generalize such an approach to human activities. In particular we consider four datasets of man-made systems and/or network mediated human activities: e-mail communication, Twitter posts, Wikipedia articles and Gutenberg books. Once we set the proper correspondence to what we consider species and individuals of a species, our approach reveals RSA is scale-free in each mentioned dataset with a power law form maintained - with roughly the same exponent - through the different human activities considered. In turn, RSA scale-invariance allows us to use activity information on local scale to predict hidden features of the human dynamics at the global scale. E-mail communication is particular relevant to illustrate our method as well as our results and possible applications. We consider the senders’ activity network where each node is a sender and a directed link from node A to node B represents an email issued from user A to user B. We set the identity of a sender to identify the species and the number of sent emails to be the individuals pertaining to a species. Thus, for instance, if user A has sent n emails we say that the species A has n individuals. Now, suppose an observer has access to a small sample of sent emails, or equivalently to partial information on links and nodes of the email communication network. Our method is capable to infer the number of nodes (i.e. the number of users) and the degree distribution (i.e. the topology) of the whole network, thus revealing features of the dynamics unknown to the observer. Moreover, our framework predicts how the number of users grows with the number of links recorded, which represents another well known pattern in ecology called the Species-Accumulation Curve (SAC). These findings may have applications in resource management, optimal network design and information diffusion on graphs. This is a work in collaboration with M. Formentin, A. Tovo and S. Favaro [1]. [1] M. Formentin, A. Tovo, S. Stivanello, S. Favaro. Ecology of human activities. In preparation, 2019+. [2] A. Tovo, S. Suweis, M. Formentin, M. Favretti, I. Volkov, J. R. Banavar, S. Azaele, A. Maritan. Upscaling species richness and abundances in tropical forests. Science Advances 3 (10) (2017) e1701438. [3] A. Tovo, M. Formentin, S. Suweis, S. Stivanello, S. Azaele. A. Maritan. Inferring macro-ecological patterns from local species’ occurrences. Methods in Ecology and Evolution, submitted, 2019. -- Dr Antonio Pievatolo IMATI-CNR http://www.imati.cnr.it/joomla/index.php/people?layout=edit&id=101 ph. +39 02 23699 520

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PhD call in Mathematics UniTn-UniVr
by Luca di persio 11 Jun '19

11 Jun '19

Dear all, the following call for PhD positions in Mathematics has been opened: PhD PROGRAMME IN MATHEMATICS University of Trento Jointly run with the University of Verona ANNOUNCEMENT OF SELECTION: 35thcycle – Academic Year 2019-2020 *DEADLINE FOR APPLICATIONS: JULY 31**, 2019,* hrs. 04.00 PM (Italian time, GMT +2) Link to the Application online <http://www.unitn.it/en/apply/dott> Positions: no. 14 Scholarships: no. 14 Supernumerary positions: no. 2 (see art. 7 of the call) __ Luca Di Persio - PhD College of Mathematics Dept. of Computer Science - University of Verona strada le Grazie 15 - 37134 Verona - Italy Tel : +39 045 802 7968 <http://www.hpa8.com/>

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New PhD position in probability at Sussex
by Enrico Scalas 10 Jun '19

10 Jun '19

Car* collegh*, vi prego di inviare questo annuncio a persone interessate. Grazie e cordiali saluti, Enrico Scalas Professor of Statistics and Probability University of Sussex UK -- PhD studentship on Large Deviation Rate Function and Variance for Inhomogeneous Corner Growth Processes Department of Mathematics, University of Sussex Supervisors: Nicos Georgiou, Enrico Scalas Deadline for application: 1 September 2019 12:00 (GMT) Details at: https://www.sussex.ac.uk/study/fees-funding/phd-funding/view/1081-PhD-stude… https://www.jobs.ac.uk/job/BSW711/phd-studentship-on-large-deviation-rate-f… Contacts: Dr Nicos Georgiou (n.georgiou(a)sussex.ac.uk) and Prof Enrico Scalas (e.scalas(a)sussex.ac.uk)

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Set valued risk measures and Systemic risk measures at LUISS
by Sara 10 Jun '19

10 Jun '19

On July 2 from 10:30 to 13:00 - Room 207, at LUISS, viale Romania 32, Roma, prof. Cagin Ararat from Bilkent University will give two talks: Talk I Title: Set-valued quasiconvex risk measures Abstract: Set-valued risk measures are defined naturally in environments where it is necessary to measure the risk of a random vector. In this talk, we consider set-valued risk measures that are defined as compositions of two set-valued functions. This class of risk measures is rich enough to cover many examples of the systemic risk measures studied in the recent literature. We pay special attention to the properties of the constituent set-valued functions that guarantee the quasiconvexity of the composite risk measure. It turns out that the so-called natural quasiconvexity property, an old but not so well-known property between convexity and quasiconvexity, plays a key role in the study of these risk measures. The main results provide dual representations for quasiconvex, naturally quasiconvex and convex compositions in terms of the dual functions of the constituents. Talk II Title: Computation of systemic risk measures Abstract: Various approaches to measure systemic risk have been proposed in the recent literature using multivariate functionals. These functionals are typically defined in terms of a so-called aggregation function, which takes into account the interconnectedness of the institutions in the network, and a univariate risk measure applied to the random output of the aggregation function. In this talk, we specialize into the Eisenberg-Noe and Rogers-Veraart network models and formulate the corresponding systemic risk measures as large-scale vector optimization problems. While the former model yields a convex problem which can be solved efficiently using non-smooth optimization techniques, the efficient frontier for the latter model turns out to be the boundary of a non-convex set. -- Sara Biagini, Professor of Mathematical Finance Department of Economics and Finance LUISS Guido Carli Address: viale Romania, 32 - 00197 Roma Web: http://sites.google.com/site/sarabiagini/

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Lecturer in Financial Mathematics at the University of Leeds
by Tiziano De Angelis 09 Jun '19

09 Jun '19

Dear All, Could you please bring to the attention of potential candidates the advert below for a lecturer position in the School of Mathematics at the University of Leeds https://jobs.leeds.ac.uk/Vacancy.aspx?ref=MAPMA1109 The deadline for application is 4 July 2019. For further information about the Probability and Financial Mathematics group at Leeds please visit https://physicalsciences.leeds.ac.uk/info/152/probability_and_financial_mat… Thank you and best wishes Tiziano

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seminario Drivas a Pisa
by Marco Romito 09 Jun '19

09 Jun '19

dear all this is to announce that Theodore Drivas (Princeton University) will give a talk on *next Wednesday, June 12* at 11am in Sala Seminari, Dipartimento di Matematica, Università di Pisa (largo B. Pontecorvo 5, 56127 Pisa). cheers m. *Title*: /Spontaneously stochastic solutions in dynamical systems with singularities/ *Abstract*: We consider a class of dynamical systems described by ordinary differential equations with an isolated singularity, where the singularity is characterized by the lack of Lipschitz continuity. Singularities are common in applications both for ODEs (e.g., particles collisions) and PDEs (e.g., finite-time blowup in fluid models). The fundamental obstacle is that solutions cannot be continued past the singularity uniquely: typically, there are infinitely many solutions. The conventional way to proceed is to define a regularization limit, such as vanishing viscosity or noise. It turns out that there are structurally stable situations when such a limit is not sensitive to a particular form of the regularization. This is explained by the analysis of attractors for the rescaled (non-singular) dynamical system and their ergodic properties. What is even more surprising is that solutions in this limit may become probabilistic (spontaneously stochastic) with the unique probability measure past the singularity. We will present rigorous results and discuss applications of this phenomenon.

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Seminario di Peter Parczewski a Bologna
by Alberto Lanconelli 08 Jun '19

08 Jun '19

Statistics Seminars 2019 Martedì 11 Giugno 2019 ore 14,30 Aula III, secondo piano, Dipartimento di Scienze Statistiche "Optimal approximation of (anticipating) SDEs" Dott. Peter Parczewski, Mannheim University Abstract We present a general mean squared error expansion for optimal approximation of Wiener functionals based on finite and equidistant observations of the Brownian motion.The expansion is given in terms of Malliavin calculus and the terms involved exhibit Hilbert space structures. This gives lower error bounds for arbitrary numerical schemes which are constructed from an equidistant information of the Brownian motion. Due to this expansion we are able to recover and improve many results on optimal approximation of Ito SDEs and anticipating SDEs, where the integral is interpreted in Skorohod sense, a mean zero extension of the Ito integral to nonadapted integrands. Tutti gli interessati sono invitati a partecipare Alberto Lanconelli Dipartimento di Scienze Statistiche "Paolo Fortunati" Alma Mater Studiorum - Università di Bologna

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Scholarships for Events on Complex Systems
by Mateusz Wilinski 07 Jun '19

07 Jun '19

We are happy to announce that the Scholarships for Events on Complex Systems (SECS) are back! They are dedicated to young researchers from Complex Systems Society, who need funds to attend complex systems related events. More information at: yrcss.cssociety.org/secs/ <https://l.facebook.com/l.php?u=http%3A%2F%2Fyrcss.cssociety.org%2Fsecs%2F%3…> Best wishes, on behalf of the YRCSS Advisory Board Mateusz Wilinski

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Seminario Gubinelli Politecnico di Torino, 12 giugno ore 15
by Enrico Bibbona 07 Jun '19

07 Jun '19

Gentili Colleghi, vi giro la pubblicità di un seminario di Massimiliano Gubinelli che si terrà qui al Politecnico di Torino mercoledì 12 giugno alle 15. http://www.politocomunica.polito.it/events/appuntamenti/(idnews)/13214 Cordiali saluti, Enrico Bibbona Enrico Bibbona Probability, Statistics and Optimization group Department of Mathematical Sciences "G. L Lagrange" Politecnico di Torino Caro Enrico, Volevo segnalarti questo seminario su Stochastic PDEs: http://www.politocomunica.polito.it/events/appuntamenti/(idnews)/13214 E’ gia’ stato mandato l’avviso dal Dipartimento ma, sai, ne riceviamo tanti e puo’ sfuggire. Gubinelli e’ una massima autorità in materia (piu’ di 2000 citazioni, lavori su Inventiones, J. Amer. Math. Soc., Comm. Pure Appl. Math., etc.) e forse puo’ interessare anche altri colleghi della tua area. Grazie, ciao, Fabio

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