Design and Interpret Ego Networks
Build a personal network around a focal actor, document the name generator and alter boundary, and interpret composition without pretending to observe the whole system.
Method sources
By the end of this tutorial
- 1Define ego-network composition and structure from an explicit node, tie, boundary, direction, weight, and observation-window specification.
- 2Apply and audit this procedure: Audit name-generator wording and nomination limits, calculate alter composition and ego degree, summarize perceived alter-alter density, and compare patterns only after checking opportunity and recall differences.
- 3Interpret the result with a sensitivity check and the following evidence boundary: An ego network is the focal participant's reported relational environment, not a census of the organization or an objective rating of every named person.
SNA
Network specification
Analysis scenario
A clerkship team asks how new medical students assemble emotional, informational, and clinical support during their first four months.
Nodes
Each consenting focal student and the people that student names through the pre-specified support prompts.
Ties
Focal-student-to-alter support nominations plus alter-alter familiarity reports when the student can answer them.
Network type
Multiple directed ego networks with typed support ties, bounded name generators, optional perceived alter-alter ties, and no claim of a complete hospital network.
Step-by-step tutorial
Freeze the relational question
Write the decision the analysis must inform, then lock the eligible node roster, tie-generating event, direction, weight, self-tie rule, observation window, and missing-data code. Preserve a read-only source copy and record why this specification represents the stated question.
Checkpoint
A second analyst can reconstruct the same node set and edge table from the written rules without guessing what an absent record means.
Compute the focal structure
Work on a versioned analysis copy and carry out the focal method exactly as specified: Audit name-generator wording and nomination limits, calculate alter composition and ego degree, summarize perceived alter-alter density, and compare patterns only after checking opportunity and recall differences. Save software and package versions, every threshold, normalization, seed, and intermediate count needed to reproduce the result.
Checkpoint
The output is tied to one named data version and includes the denominator, parameter settings, and a reproducible calculation record.
Run a structural sensitivity check
Repeat the analysis under at least one defensible alternative boundary, missingness rule, tie threshold, weight transformation, or model setting. Compare membership and substantive conclusions, not only a single coefficient, and investigate every change large enough to alter a decision.
Checkpoint
The audit states which patterns persist, which actors or groups change classification, and which conclusion depends on an analyst choice.
Report for responsible action
Pair the numerical result with a table or structure-preserving visual, document excluded and missing actors, and explain uncertainty in plain language. Convert the finding into a reversible support question, not an automatic ranking, while stating this boundary: An ego network is the focal participant's reported relational environment, not a census of the organization or an objective rating of every named person.
Checkpoint
The final note contains the question, specification, result, sensitivity evidence, uncertainty, privacy controls, and a proportionate next step.
Interpret with care
ego-network composition and structure describes a property of the specified relation and network boundary. It does not transfer automatically to another relation, time period, class, platform, or population.
An ego network is the focal participant's reported relational environment, not a census of the organization or an objective rating of every named person. Compare the result with raw counts, missingness, plausible alternative specifications, and contextual evidence before acting.