Stochastic blockmodeling of linked networks

Škulj, Damjan (author), Žiberna, Aleš (author)

Blockmodeling linked networks aims to simultaneously cluster two or more sets of units into clusters based on a network where ties are possible both between units from the same set as well as between units of different sets. While this has already been developed for generalized and k-means blockmodeling, our approach is based on the well-known stochastic blockmodeling technique, utilizing a mixture model. Estimation is performed using the CEM algorithm, which iteratively estimates the parameters by maximizing a suitable likelihood function and reclusters the units according to the parameters. The steps are repeated until the likelihood function ceases to improve. A key drawback of the basic algorithm is that it treats all units equally, consequently yielding higher influence to larger parts of the data. The greater size, however, does not necessarily imply higher importance. To mitigate this asymmetry, we propose a solution where underrepresented parts of the data are given more influence through an appropriate weighting. This idea leads to the so-called weighted likelihood approach, where the ordinary likelihood function is replaced by a weighted likelihood. The efficiency of the different approaches is tested via simulations. It is shown through simulations that the weighted likelihood approach performs better for larger networks and a clearer blockmodel structure, especially when the one-mode blockmodels within the smaller sets are clearer.

• Language: English
• Keywords: stochastic blockmodeling, linked network, weighted likelihood, CEM algorithm, mixture model
• Work type: Article
• Typology: 1.01 - Original Scientific Article
• Organization: FDV - Faculty of Social Sciences
• Publication status: Published
• Publication version: Version of Record
• Year: 2022
• Number of pages: Str. 240-252
• Numbering: Vol. 70
• PID: 20.500.12556/RUL-135305
• UDC: 303:004.42
• ISSN on article: 0378-8733
• DOI: 10.1016/j.socnet.2022.02.001
• COBISS.SI-ID: 98506755
• Publication date in RUL: 07.03.2022

Record is a part of a journal

• Title: Social networks
• Shortened title: Soc. networks
• Publisher: Elsevier
• ISSN: 0378-8733
• COBISS.SI-ID: 30632960

Licences

• License: CC BY-NC-ND 4.0, Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International
• Link: http://creativecommons.org/licenses/by-nc-nd/4.0/
• Description: The most restrictive Creative Commons license. This only allows people to download and share the work for no commercial gain and for no other purposes.
• Licensing start date: 19.02.2022

Secondary language

• Language: Slovenian
• Keywords: stohastično bločno modeliranje, analiza omrežij, družbene vede, bločno modeliranje