Καλησπέρα,
Είναι μεγάλη τιμή για το τμήμα μας που ένας μαθηματικός όπως ο
Frank den Hollander θα δώσει ομιλία στο τμήμα μας.
Όσοι προπτυχιακοί φοιτητές πλησιάζουν στο τέλος των σπουδών τους και
έχουν ενδιαφέρον για μεταπτυχιακά θα ήταν καλό να παρευρεθούν στην ομιλία.
Γενικό Σεμινάριο
Παρασκευή 16 Μαΐου στις 13:10
Αίθουσα Γ32
Frank den Hollander, Leiden University, The Netherlands
https://www.universiteitleiden.nl/en/staffmembers/frank-den-hollander#tab-1
Τίτλος: The friendship paradox for social networks
Περίληψη: Consider a group of individuals who form a social network. For
each individual in the group, compute the difference between the average
number of friends of its friends and the number of its friends (all
friendships are mutual), and average these numbers over all the
individuals in the group. It turns out that the latter average is always
non-negative, and is strictly positive as soon as not all individuals have
exactly the same number of friends. This bias, which at first glance seems
counterintuitive, goes under the name of friendship paradox, even though
it is a hard fact.
In this talk we model the social network as a graph and explain where the
bias comes from. For two examples of random graphs we show how the bias
can be quantified. We briefly discuss variants where we look at groups of
friends.
Based on joint work with R.S. Hazra (Leiden) and A. Parvaneh (Leiden).
http://users.uoa.gr/~strevezas/Seminar-MATH-gen/
