First announcement MODEL SELECTION DAY (this time in Prague) to be held on September 16, 2009 (Wednesday) in the Institute of Information Theory and Automation of the ASCR Pod Vodarenskou vezi 4, CZ-18208, Prague 8, Czech Republic the room number 3 (How to get there: http://www.utia.cas.cz/contacts ) Organized by Milan Studeny and Frantisek Matus (from the above-mentioned institute) The speakers, titles, abstracts and preliminary schedule: 10:30-11:30 Prof. Joe Whittaker, Lancaster University, UK Title: A survey of some issues that arise in statistical model selection. Abstract: Statistical model selection has for many years been of interest to the academic and scientific profession. Here we discuss some of the current issues and, in particular, make a comparison to what was available thirty years ago. 11:30-11:45 coffee break 11:45-12:45 Prof. Raymond Hemmecke, University of Darmstadt & Otto-von-Guericke University Magdeburg, Germany Title: Polytopes of Bayesian network structures. Abstract: In this talk we consider polytopes associated to Bayesian network structures. The study of these polytopes is fundamental for improving existing algorithms for learning such Bayesian network structures. By restricting our attention to special Bayesian networks, e.g. those that have an undirected tree or forest as the essential graph, we obtain very nice structural results on these associated polytopes. In particular, they allow us to give a mathematical proof that the GES algorithm (greedy equivalence search) is guaranteed to find an optimal Bayesian network structure of the pre-described special type. We give an example that this need not be the case in the general case. [This is joint work with Silvia Lindner, Milan Studeny and Jirka Vomlel.] 12:45-14:00 lunch break 14:00-15:00 Dr. Nihat Ay, Max Planck Institute Liepzig, Germany & External Professor at Santa Fe Institute (US) Title: Maximizing the multi-information of stochastic processes. Abstract: I will discuss various approaches to the geometry of the set of stochastic matrices motivated by information geometry. Based on this, I introduce a notion of multi-information for stochastic processes and study the corresponding maximization problem. The main result sets bounds on the entropy of a Markov process with maximal multi-information. Finally, I comment on some open problems related to the Kolmogorov-Sinai entropy of dynamical systems. 15:00-15:15 coffee break 15:15-16:15 Dr. Frantisek Matus, Academy of Sciences of the Czech Republic Title: Limiting in closures of exponential families. Abstract: The closures of exponential families of probability measures in the variation distance and reversed information divergence have been used to understand better the optimization of likelihood and entropies. Existing results on the closures will be reviewed, including a quantum setting if time permits. For the standard exponential families on Euclidean spaces with finite supports limiting in the mean parametrization towards the boundary can be described in a considerable detail. This provides a control of the behavior of information divergences and variance functions around boundaries. Resulting expansions of variance functions at boundary points are used to prove that an exponential family has a finite support and quadratic variance function if and only if it is the product of multinomial families up to an affine transformation. REMARK: The time schedule is tentative at this moment. It may be changed later to address traveling possibilities of registered participants. ADDITIONAL INFORMATION for potential (traditional Model Selection Day) participants from Germany: There is a train EN457 (Phoenix) from Dresden to Prague arriving in Praha, hl.n. at 9:56. This main Prague's railway station "Hlavni nadrazi" is on metro line C (red line): 5 stops from "Ladvi" metro station, which is in 7 minutes walking from the Institute of Information Theory and Automation. There is a train EC170 (Hungaria) from Prague to Berlin departing from Praha-Holesovice at 16:40. This railway station "Nadrazi Holesovice" is also on metro line C, 2 stops from Ladvi metro station. The preliminary schedule above is designed in such a way that one can use both train connections (provided there is no unexpected delay in the city transport). However, for those who prefer to have accommodation in Prague (not far from the institute) some hotel contacts: - M pension, Davidkova 2143/94, 18200 Praha 8, www.pension-m.cz, info@pension-m.cz, tel. +420-283880827, fax +420-283882384 - pension "Pod Zvoneckem", Strelnicna 761/45, 18000 Praha 8 www.podzvoneckem.cz , recepce@podzvoneckem.cz, tel. +420-777999559 - pension "Garni Hotel Hanauer", Ke Stirce 26, Praha 8, www.hanauer.cz, hanauer@volny.cz, tel. +420-284680905, fax +420-284681703 - hotel Jerabek, Primatorska 4/7, 18000 Praha 8, www.jerabekhotel.cz, info@jerabekhotel.cz, tel. +420-283841919, fax +420-283841816 The potential foreign participants are expected to find their accommodation themselves. Nevertheless, those who intend to participate in the seminar are asked to "register" by writing a message to studeny@utia.cas.cz with subject "MSD in Prague". We would appreciate this information: name, affiliation, expected arrival and departure (in case of non-local participants). There will be no conference fee, but this information is necessary to organize coffee/lunch breaks and to have a suitable room for the seminar. We are also considering an idea to have an informal dinner together with those participants that will stay in Prague after the seminar in a brewery in downtown Prague.