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networkx.algorithms.assortativity.degree_pearson_correlation_coefficient

degree_pearson_correlation_coefficient(G, x='out', y='in', weight=None, nodes=None)[source]

Compute degree assortativity of graph.

Assortativity measures the similarity of connections in the graph with respect to the node degree.

This is the same as degree_assortativity_coefficient but uses the potentially faster scipy.stats.pearsonr function.

Parameters
  • G (NetworkX graph)

  • x (string (‘in’,’out’)) – The degree type for source node (directed graphs only).

  • y (string (‘in’,’out’)) – The degree type for target node (directed graphs only).

  • weight (string or None, optional (default=None)) – The edge attribute that holds the numerical value used as a weight. If None, then each edge has weight 1. The degree is the sum of the edge weights adjacent to the node.

  • nodes (list or iterable (optional)) – Compute pearson correlation of degrees only for specified nodes. The default is all nodes.

Returns

r – Assortativity of graph by degree.

Return type

float

Examples

>>> G=nx.path_graph(4)
>>> r=nx.degree_pearson_correlation_coefficient(G)
>>> print("%3.1f"%r)
-0.5

Notes

This calls scipy.stats.pearsonr.

References

1

M. E. J. Newman, Mixing patterns in networks Physical Review E, 67 026126, 2003

2

Foster, J.G., Foster, D.V., Grassberger, P. & Paczuski, M. Edge direction and the structure of networks, PNAS 107, 10815-20 (2010).