Choose Directed or Undirected Ties
Match edge direction to the relation instead of discarding who initiated, nominated, sought, or received an interaction.
Method sources
By the end of this tutorial
- 1Define edge direction and reciprocity from an explicit node, tie, boundary, direction, weight, and observation-window specification.
- 2Apply and audit this procedure: Preserve the ordered sender-receiver pair, calculate in-degree, out-degree and reciprocity, then compare with an undirected symmetrization using both union and intersection rules.
- 3Interpret the result with a sensitivity check and the following evidence boundary: Symmetrizing can erase status, access, initiative, and nonreciprocity; direction indicates the recorded relation, not authority, trust, or quality by itself.
SNA
Network specification
Analysis scenario
A school wants to map who seeks teaching advice from whom and must decide whether mutual-looking pairs should be collapsed into undirected connections.
Nodes
All teachers employed at the school on the census date, including eligible nonrespondents and isolates.
Ties
A directed nomination from teacher A to teacher B when A sought substantive teaching advice from B during the term.
Network type
One-mode, directed, binary whole network with no self-ties, one term-long window, and explicit unknown values for nonrespondents.
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: Preserve the ordered sender-receiver pair, calculate in-degree, out-degree and reciprocity, then compare with an undirected symmetrization using both union and intersection rules. 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: Symmetrizing can erase status, access, initiative, and nonreciprocity; direction indicates the recorded relation, not authority, trust, or quality by itself.
Checkpoint
The final note contains the question, specification, result, sensitivity evidence, uncertainty, privacy controls, and a proportionate next step.
Interpret with care
edge direction and reciprocity describes a property of the specified relation and network boundary. It does not transfer automatically to another relation, time period, class, platform, or population.
Symmetrizing can erase status, access, initiative, and nonreciprocity; direction indicates the recorded relation, not authority, trust, or quality by itself. Compare the result with raw counts, missingness, plausible alternative specifications, and contextual evidence before acting.