8
$\begingroup$

i am working to create a mapping of the adjacencies between 100 consumer goods. I have created an adjacency matrix based on product characteristics, and then create an i-graph of the graph/network (using tkplot / igraph)

I am using the fruchterman reingold force-directed mapping algo to place the vertices, and get a nice picture of a 8-10 connected cliques.

Probably partly due to lack of understanding on how forec-directed mapping algos really work(and maybe should require me to do a lot more basic studying), but does the positioning of different cliques across the "page" by the fruchterman-rheingold algorhytm contain any information. E.g. - does the fact that i have two cliques in the bottom right corner, a small clique in the middle and a massive clique in the top left corner say anything about the characteristics / similarities between these cliques, or is just random spacing across the space to improve visual clarity?

Apologies if not clear - W

enter image description here

$\endgroup$
1
  • $\begingroup$ Yes, there is information in the placement, for example centrality. Perhaps it is possible for you to add a link to the data or show a picture of the graph? $\endgroup$
    – FredrikD
    Jul 11, 2013 at 18:00

1 Answer 1

3
$\begingroup$

If the subgraphs are not connected to each other, as in your picture, then their relative placement is arbitrary. Fruchterman-Reingold layout is only based on connections.

$\endgroup$
2
  • $\begingroup$ Exactly. The vertices within components are placed "non-randomly", the placement of the components is essentially arbitrary. $\endgroup$ Jul 13, 2013 at 0:30
  • $\begingroup$ @user19856 has suggested the following "minor characteristicos implementation": There are some "variations" of the same method: some "fix" one vertice on centrer of picture and let the other "to gravite" around it. I dont know how these implementatins works, but if you look the code, perhaps you can fix some vertice (e.g. the most connected) AADF $\endgroup$ Jul 17, 2013 at 14:32

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge that you have read and understand our privacy policy and code of conduct.

Not the answer you're looking for? Browse other questions tagged or ask your own question.