Albert-Ludwigs-Universität Freiburg  ·  Social Network Analysis Case Study
Case Study  ·  Social Network Analysis

Unlocking Organisational Intelligence
from Communication Data

A demonstration of how Social Network Analysis transforms raw email interaction data into actionable insights about collaboration patterns, influence, and team dynamics.

📅 2024-01-01 – 2026-03-13 ✉ 12,216 emails analysed 👤 89 anonymised individuals 🏢 European research institution

What can your data tell you?

Most organisations hold years of communication data — emails, chats, collaboration logs — and extract almost no strategic value from it. Social Network Analysis changes that. By modelling individuals as nodes and their interactions as weighted, directed edges, we surface the hidden structure of how your organisation actually works — not just how it appears on an org chart.

Total people
89
anonymised individuals
Unique links
1,506
directed relationships
Total emails
12,216
over ~802 days
Network density
19%
of all possible links active
Reciprocity
70%
of links are two-way
Communities
6
natural sub-groups detected
Modularity
0.4303
community cohesion score
Avg path length
1.86
hops between any two people
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Key Takeaway

With a reciprocity of 70%, the vast majority of communication is genuinely bidirectional. An average path length of 1.86 hops means information reaches almost anyone in fewer than 2 steps — a hallmark of a healthy small-world network. A modularity of 0.4303 reveals clear team boundaries without isolation.

Visualising the Organisation as a Network

Each node represents a person. Each edge is a communication channel. Node size reflects overall influence (PageRank), and colour indicates which natural community the algorithm assigned each person to — without any prior knowledge of the org chart.

Network Graph
Figure 1 — Communication Network Graph. 6 distinct communities emerge automatically from email patterns alone. Labelled nodes (largest circles) are the most influential individuals. Tightly clustered groups correspond to teams; nodes bridging clusters are critical information brokers.
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What this reveals

The algorithm identified 6 natural communities from email behaviour alone — no org-chart labels required. Cross-community edges highlight where inter-departmental collaboration occurs. Thin bridges flag bottlenecks: a single person carrying all cross-team communication. Losing that person means losing that connection.

When Does Your Organisation Communicate?

Timestamps on every message let us analyse not just who talks to whom, but when. This reveals work rhythms, crunch periods, after-hours activity, and potential early burnout signals.

Weekly Volume
Figure 2 — Weekly email volume, 2024-01-01 to 2026-03-13. The dashed line shows the 4-week rolling average, revealing long-term activity trends. Spikes may correspond to project deadlines, conference seasons, or grant submissions. Sustained low-volume periods can indicate seasonal slowdowns or disengagement.
Activity Heatmap
Figure 3 — Email volume by hour of day and day of week (local time). Darker cells = higher communication volume. The concentration on weekday business hours (approx. 08:00–18:00) confirms typical academic office patterns. Weekend and late-night activity would surface here immediately if present.

Operational applications

Temporal analysis answers: Are people working unusual hours? When are deadlines driving communication spikes? Is one team systematically sending messages outside business hours? These signals are invisible in aggregated reports but surface instantly here.

Who Are the Real Leaders?

Beyond the org chart, SNA quantifies actual influence. We combine four independent metrics — PageRank, betweenness centrality, in-degree, and reciprocity — into a composite influence score, then assign each person a functional network role.

Key Influencer
35 nodes (39%)

Central nodes with the highest combined influence, popularity, and reach. These individuals drive information flow across the entire organisation.

Bridge / Broker
1 nodes (1%)

Nodes that connect otherwise separate groups. Removing them would fragment the network. Critical for cross-team knowledge transfer.

Information Hub
1 nodes (1%)

Highly popular receivers. Many colleagues reach out to them, making them focal points for information aggregation.

Collaborator
9 nodes (10%)

Nodes with high reciprocity — conversations are genuinely two-way. Strong bilateral relationships and mutual engagement.

Peripheral
43 nodes (48%)

Nodes at the edges of the network. May be specialists, newcomers, or siloed contributors with lower overall engagement.

Role Scatter
Figure 4 — Influence vs. Brokerage. X-axis: PageRank (how influential). Y-axis: Betweenness (how much of a broker). Bubble size: in-degree (popularity). Top-right nodes are both influential and structurally critical — removing them disrupts the entire network.
Centrality Comparison
Figure 5 — Multi-dimensional centrality for top 15 nodes. Four independent metrics side by side. A node scoring high on all four is a true organisational linchpin. Diverging scores reveal specialised roles (e.g., high betweenness but low in-degree = a quiet broker).

Top 10 Most Influential Individuals

RankNodeRoleCommunity In-DegreeOut-Degree PageRankBetweennessReciprocity Influence Score
#1 Node 54 Key Influencer Dept 3 615 637 0.04269 0.0214 0.806
0.7478
#2 Node 60 Key Influencer Dept 4 569 645 0.04353 0.0121 0.784
0.7057
#3 Node 25 Key Influencer Dept 4 475 390 0.03565 0.0338 0.792
0.6796
#4 Node 48 Key Influencer Dept 3 313 453 0.02355 0.0822 0.73
0.6792
#5 Node 49 Key Influencer Dept 3 384 547 0.02666 0.0486 0.696
0.6098
#6 Node 30 Key Influencer Dept 5 226 125 0.0141 0.0856 0.667
0.5698
#7 Node 16 Key Influencer Dept 4 378 187 0.03255 0.0066 0.9
0.5353
#8 Node 24 Key Influencer Dept 6 460 338 0.02732 0.0161 0.781
0.5352
#9 Node 88 Key Influencer Dept 4 177 298 0.01551 0.0714 0.806
0.531
#10 Node 35 Key Influencer Dept 4 314 391 0.02295 0.0347 0.627
0.4974
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Why this matters

Traditional reporting identifies leaders by title. SNA identifies them by actual communication behaviour. Key Influencers are the real opinion-shapers for change management. Brokers are the people whose departure creates knowledge silos. Information Hubs are overloaded focal points — candidates for delegation support or process automation.

How Do Teams Collaborate?

Community detection reveals organic groupings that emerge from behaviour, not hierarchy. Comparing internal vs. cross-department communication per community shows which teams are siloed and which are highly collaborative. A modularity of 0.4303 indicates strong community structure — teams are clearly distinct with limited cross-boundary traffic.

Community Communication
Figure 6 — Internal vs cross-department email volume per community. Blue bars = emails within the community. Green bars = emails to/from other communities. A dominant green bar indicates high cross-team collaboration. A dominant blue bar may signal a self-sufficient team — or a silo.
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Detecting silos before they become problems

An imbalance between internal and cross-department communication is an early warning sign of organisational siloing. With real customer data, this analysis pinpoints exactly which teams are not communicating — and whether this is intentional (specialist isolation) or problematic (missed collaboration opportunities).

What Can You Do With This?

The analyses demonstrated here apply directly to a wide range of real-world organisational challenges. With richer, labelled customer data, each use case becomes a concrete, decision-ready product delivered on your data.

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Change Management & Adoption

Identify the true influencers before rolling out a new tool or policy. Target them first — they cascade adoption through the network organically.

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Bottleneck & Burnout Detection

Information Hubs with extreme in-degree are receiving far more than they can process. Surface overload signals before productivity drops or attrition occurs.

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Succession Planning

When a Key Influencer or Broker leaves, critical network links disappear with them. SNA identifies institutional knowledge holders and structural dependencies in advance.

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Team Structure Optimisation

Detected communities vs. official org chart — where do they diverge? Reorganise teams around actual collaboration patterns, not legacy hierarchy.

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Onboarding Acceleration

New hires who connect to central nodes integrate faster. Route introductions through the most-connected colleagues to cut time-to-productivity.

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Anomaly & Risk Detection

Sudden changes in communication patterns — a node going silent, a new dense cluster forming — can signal conflict, disengagement, or data risk weeks before it appears in conventional reporting.

How Was This Built?

This case study was produced entirely from a raw edge-list file with three columns: sender, receiver, timestamp. No labels, no names, no metadata. Everything you see was derived from communication structure alone.

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Data

12,216 directed, timestamped email edges spanning 802 days across 89 anonymised nodes. Source: SNAP / Stanford.

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Graph Analysis

NetworkX (Python). Metrics: PageRank, betweenness, closeness, in/out-degree, reciprocity, clustering.

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Community Detection

Louvain algorithm on weighted undirected projection. Modularity = 0.4303 (strong community structure).

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Visualisation

Matplotlib & Seaborn, Uni Freiburg corporate design palette. Spring-layout force-directed network.