This is a graph of Peertube instances following each other. There are 942 nodes and 10067 edges.

Eigenvector centrality

On Peertube, an instance X can follow an instance Y to let its users see all the videos posted on Y. This graph is a directed graph.

Color and size of nodes depends on how big their Eigenvector centrality is. Nodes which have 0 centrality are blue and small, nodes with bigger centrality are big and red.

What centrality represents? Instances which are not followed by anyone have 0 centrality. Instances (A) with a lot of followers (B) have bigger centrality. If those followers (B) themselves have followers ©, it means centrality of A will be even higher.

Does it mean anything in context of Peertube? I’m not sure. Considering chain of three instances: (A) <- (B) <- ©, when (A) posts a video, does it appear in ©? Probably not. But if it was so, then centrality would’ve mean this: Videos posted on instances with high centrality spread across entire network, while videos posted on instances with 0 centrality are not visible anywhere else.

Here are top 10 instances and their centrality:

How to repeat this graph visualization

  1. Download latest Peertube instances.csv and interactions.csv files here: https://www.kaggle.com/datasets/marcdamie/fediverse-graph-dataset-reduced
  2. Import them to Gephi;
  3. Apply Giant Component filter to remove nodes which are not connected to biggest network;
  4. Apply ForceAtlas 2 layout;
  5. Run Eigenvector centrality Statistics (directed). It will add a new column to nodes table;
  6. Apply Nodes - Color - Ranking - Eigenvector centrality;
  7. Apply Nodes - Size - Ranking - Eigenvector centrality;
  8. Configure Preview and export.

Gephi

P.S. On colorful image used as thumbnail of this post nodes are colored by Modularity (community detection).

  • podbrushkin@mander.xyzOP
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    23 days ago

    Why do you think Gephi is using Graphviz? I think it does not. In graphviz there is no Giant Component filter and no centrality statistics, which are part of graph theory. Gephi is closer to graph theory than graphviz is. Graphviz does have some good node placement algorithms, but in general these apps have different scope. Graphviz is a no go for this purpose.

    Gephi, NetworkX or iGraph - pick single one of these and it will be a single tool you need to repeat steps in the post and achieve similar result. But latter two are programming libraries. Managing to get and launch Gephi probably worth the hassle.

    • plantteacher@mander.xyz
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      10 days ago

      Why do you think Gephi is using Graphviz?

      I don’t get on here often so now I have forgotten what gave me that impression.

      Gephi, NetworkX or iGraph

      Thanks for the tip! Debian officially has a r-cran-igraph pkg, so perhaps I should start by tinkering with that.