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Presentations Annual Meeting are Online!

29th of March 2017
Last week, the annual meeting was a succes. We thank all ±160 attendants for making this meeting a succes!   Read more...

Room 417

22nd of March 2017
The VvS+PR Annual Meeting is held in Room 417 of the Jaarbeurs (Beatrix building).

General Members Meeting Documents online!

12th of March 2017
To see the documents, make sure you have your login information. Please find the documents at: Read more...

Conference of European Statistics Stakeholders - call for abstracts

20th of April 2016
Submit your abstract and participate to the Second Conference of European Statistics Stakeholders, that will be held in Budapest, 20-21, October 2016. Read more...

Werk mee aan internationale normen voor statistische methoden voor Six Sigma, QFD en SPC

18th of December 2015
Voldoet mijn product aan kwaliteitseisen? Hoe kan ik mijn processen efficiënter maken? Sluit mijn product aan bij de wensen van de klant of andere stakeholders?   Read more...

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Next Mark Kac seminar

Where:  Utrecht, Janskerkhof 15a, room 101
When:  2nd of June 2017
Starttime  11.15


Friday June 2
Utrecht, Janskerkhof 15a, room 101

11:15-13:00
Speaker: Pierre Nolin (ETH Zürich)
Title  : Near-critical percolation and self-organized criticality in
         two dimensions

14:30-16:15
Speaker: Diego Garlaschelli (Leiden)
Title  : Breaking of ensemble equivalence in networks


Abstract Pierre Nolin
We discuss several two-dimensional lattice models displaying a form of 
self-organized criticality. The behavior of these models is related to
the phase transition of independent site percolation, which is now very
well understood in two dimensions. In particular, we study the frozen
percolation model (where connected components of vertices stop growing
when they get too large), and we present a connection with forest-fire
processes (where  lightning hits independently each vertex with a small
rate, and burns its entire connected component immediately).
 
This talk is based on joint works with Rob van den Berg (CWI and VU, 
Amsterdam) and Demeter Kiss.


Abstract Diego Garlaschelli
It is generally believed that, in the thermodynamic limit, the
microcanonical description as a function of energy coincides with the
canonical description as a function of temperature. However, various
examples of systems for which the microcanonical and canonical ensembles
are not equivalent have been identified. A complete theory of this
intriguing phenomenon is still missing. Here we show that ensemble
nonequivalence can manifest itself also in random graphs with
topological constraints. We find that, while graphs with a given number
of links are ensemble-equivalent, graphs with a given degree sequence
are not. This result holds irrespective of whether the energy is
nonadditive (as in unipartite graphs) or additive (as in bipartite
graphs). In contrast with previous expectations, our results show that:
(1) physically, nonequivalence can be induced by an extensive number of
local constraints, and not necessarily by long-range interactions or
nonadditivity; (2) mathematically, nonquivalence is determined by a
different large-deviation behaviour of microcanonical and canonical
probabilities for a single microstate, and not necessarily for almost
all microstates. The latter criterion, which is entirely local, is not
restricted to networks and holds in general. We also show that the
relative canonical fluctuations of the  constraints do not vanish, and
generalise our main results to the case of multi-layer graphs with an
arbitrary distribution of intra-layer and  inter-layer degrees.


The Mark Kac seminar is supported by FOM and is an activity of the STAR
stochastics cluster. See also our website http://www.win.tue.nl/markkac

More information:  [comment]
Telephone:  [rooster_phone]
e-mail: 

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The tenth Stochastic Activity Month

EURANDOM in Eindhoven
4th of September 2017 - 8th of September 2017 Read more...

“Networks: Probability, Combinatorics and Algorithms”

Eurandom, Eindhoven
4th of September 2017 - 8th of September 2017 Read more...

“Randomness and Graphs: Processes and Structures

Eurandom, Eindhoven
11th of September 2017 - 15th of September 2017 Read more...

“Community Detection and Network Reconstruction”

Eurandom, Eindhoven
19th of September 2017 - 22nd of September 2017 Read more...

Lunteren Meeting

`De Werelt' in Lunteren
13th of November 2017 - 15th of November 2017 Read more...


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