Hi Miguel, the LocalClusteringCoefficient algorithm returns a DataSet of type Result, which basically wraps a vertex id, its degree, and the number of triangles containing this vertex. The number 11 you see is indeed the degree of vertex 5113. The Result type contains the method getLocalClusteringCoefficientScore() which allows you to retrieve the clustering coefficient score for a vertex. The method simply divides the numbers of triangles by the number of potential edges between neighbors.
I'm sorry that you this is not clear in the docs. We should definitely improve them to explain what is the output and how to retrieve the actual clustering coefficient values. I have opened a JIRA for this [1]. Cheers, -Vasia. [1]: https://issues.apache.org/jira/browse/FLINK-5597 On 20 January 2017 at 19:31, Miguel Coimbra <miguel.e.coim...@gmail.com> wrote: > Hello, > > In the documentation of the LocalClusteringCoefficient algorithm, it is > said: > > > *The local clustering coefficient measures the connectedness of each > vertex’s neighborhood.Scores range from 0.0 (no edges between neighbors) to > 1.0 (neighborhood is a clique).* > > https://ci.apache.org/projects/flink/flink-docs-release-1.1/ > apis/batch/libs/gelly.html#local-clustering-coefficient > <https://ci.apache.org/projects/flink/flink-docs-master/dev/libs/gelly/library_methods.html#local-clustering-coefficient> > > However, upon running the algorithm (undirected version), I obtained > values above 1. > > The result I got was this. As you can see, vertex 5113 has a score of 11: > (the input edges for the graph are shown further below - around *35 edges* > ): > > (4907,(1,0)) > *(5113,(11,0))* > (6008,(0,0)) > (6064,(1,0)) > (6065,(1,0)) > (6107,(0,0)) > (6192,(0,0)) > (6252,(1,0)) > (6279,(1,0)) > (6465,(1,0)) > (6545,(0,0)) > (6707,(1,0)) > (6715,(1,0)) > (6774,(0,0)) > (7088,(0,0)) > (7089,(1,0)) > (7171,(0,0)) > (7172,(1,0)) > (7763,(0,0)) > (7976,(1,0)) > (8056,(1,0)) > (9748,(1,0)) > (10191,(1,0)) > (10370,(1,0)) > (10371,(1,0)) > (14310,(1,0)) > (16785,(1,0)) > (19801,(1,0)) > (26284,(1,0)) > (26562,(0,0)) > (31724,(1,0)) > (32443,(1,0)) > (32938,(0,0)) > (33855,(1,0)) > (37929,(0,0)) > > This was from a small isolated test with these edges: > > 5113 6008 > 5113 6774 > 5113 32938 > 5113 6545 > 5113 7088 > 5113 37929 > 5113 26562 > 5113 6107 > 5113 7171 > 5113 6192 > 5113 7763 > 9748 5113 > 10191 5113 > 6064 5113 > 6065 5113 > 6279 5113 > 4907 5113 > 6465 5113 > 6707 5113 > 7089 5113 > 7172 5113 > 14310 5113 > 6252 5113 > 33855 5113 > 7976 5113 > 26284 5113 > 8056 5113 > 10371 5113 > 16785 5113 > 19801 5113 > 6715 5113 > 31724 5113 > 32443 5113 > 10370 5113 > > I am not sure what I may be doing wrong, but is there perhaps some form of > normalization lacking in my execution of: > > org.apache.flink.graph.library.clustering.undirected. > LocalClusteringCoefficient.Result; > org.apache.flink.graph.library.clustering.undirected. > LocalClusteringCoefficient; > > Am I supposed to divide all scores by the greatest score obtained by the > algorithm? > > Thank you very much! > > Miguel E. Coimbra > Email: miguel.e.coim...@gmail.com <miguel.e.coim...@ist.utl.pt> > Skype: miguel.e.coimbra >
