  This study deals with the stability evaluation of the online community of
Russian sociologists. Based on the data from the Facebook group, which consists
of 7 years of communication from 2011 till 2018, we constructed the networks
based on commenting and reacting. The participants activity includes four main
periods for stability evaluation of the community. The blockmodeling discloses
the structural patterns of interactions in the community. The results show the
"core-periphery" type of the global structure. The core and periphery are
structured differently in the networks of comments and reactions. The stability
between the positions in the global structure is high and while the structure
may vary in some periods, the size of the core and periphery fluctuates.
However, the stability within the positions of the global structure is low,
according to the modified Rand index (Cugmas, Ferligoj, 2018).
