Question 6 - Communities

In the online realm Streamland, users form alliances by sharing videos. Two users are connected if they frequently co-watch and comment on each other’s uploads. Over time, the network develops dense friendship clusters separated by a few key influencers who connect multiple groups.

The Streamland Council wants to identify real communities within this network. They test two algorithms:

  • Ravasz’s agglomerative method
  • Girvan-Newman’s divisive method

If one influential user bridges two dense fan groups, which algorithm is more likely to identify these two fan groups as separate communities?

A) Both algorithms, because they detect bridge users the same way

B) Ravasz’s method, because it merges nodes based on global similarity rather than edge centrality

C) Girvan-Newman’s method, because removing high-betweenness links isolates the two dense groups

D) Ravasz’s method, because topological overlap decreases across sparse bridges

E) None of the above

Original idea by: Jhonatan Cléto

Comentários

  1. Joao Meidanis15 de novembro de 2025 às 07:18

    Questão difícil, eu não saberia resolver. A (A) parece ter a conclusão correta, mas não creio que a razão seja a descrita.

    ResponderExcluir

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