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E-I Index/Evidence
Method evidence record

E-I Index

The external-internal (E-I) index, introduced by Krackhardt and Stern, measures the extent to which the ties of a group point outward to other groups versus inward to its own members. It is the number of between-group (external) ties minus the number of within-group (internal) ties, divided by the total number of ties. Ranging from −1 (all ties internal, perfect insularity) to +1 (all ties external), it is a compact summary of homophily and group closure that can be computed for a whole network, for each group, or for each node.

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Source record

Citations copied verbatim from the method’s source record. No claim-level verification is inferred from them.

Krackhardt-Stern External-Internal (E-I) Index
Taxonomic method record · process-pipeline / sociology
  • Krackhardt, D., & Stern, R. N. (1988). Informal networks and organizational crises: An experimental simulation. Social Psychology Quarterly, 51(2), 123–140. · DOI 10.2307/2786835
  • Everett, M. G., & Borgatti, S. P. (2012). Categorical attribute based centrality: E-I and G-F centrality. Social Networks, 34(4), 562–569. · DOI 10.1016/j.socnet.2012.06.002
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Related methods

Generated from the method graph and shown as machine-suggested relations — no evidence claim is inferred.

Same method familyBlockmodelingmachine-suggested · Relational suggestion, not evidence.Used in the same domainDyadic Analysismachine-suggested · Relational suggestion, not evidence.Same method familyHomophily Analysismachine-suggested · Relational suggestion, not evidence.Same method familyIsolation Indexmachine-suggested · Relational suggestion, not evidence.See alsoSocial Network Analysismachine-suggested · Relational suggestion, not evidence.

Evidence status

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Sources

2 recorded citations, copied from the method source record.

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