networkStat returning redundant vertex statistics in several columns

[clithero]

Hello -

I am trying to use the networkStat() function to get various vertex statistics. However, several of the columns are giving the exact same numbers. When I run the following:

NM <- biblioNetwork(M, analysis = "coupling", network = "references")
NMstat <- networkStat(NM,stat="all",type="all")

the output for three variables saved in "vertex" are the exact same for all articles: vertexCentrEigen, vertexHub, and VertexAuthority.

I have tried this for two different sets of articles and the same problem occurs. So, two questions.

1. I am assuming this is an error? If not, why are they the same?
2. If an error, which of these three is the one being repeated?

Thank you!