OCHA and UNHCR Are the Network's Densest Hubs , Chord Thickness Encodes Coordination Strength Figure 28.1 , OCHA and UNHCR Are the Network's Densest Hubs

A non-ribbon chord diagram is a circular relationship graph : nodes are arranged as arc segments on the perimeter of a circle, and connections are drawn as curved lines (chords) spanning the interior. The perceptual mechanism is gestalt continuity , the eye follows each curve from one arc to another, reading the connection as a single unit even when it crosses other chords. The circular layout implies no hierarchy (all nodes are equidistant from the center) and no direction (chords are symmetric).

A full ribbon chord diagram fills the space between two arcs with a shaped "ribbon," encoding directional flow volume: the width of the ribbon at each end represents how much flows from that node. This is appropriate when data has meaningful direction (migration, trade, financial flows) and when per-direction volumes are precisely known. A non-ribbon chord diagram strips the filled shape away, keeping only the connection lines.

A force-directed network graph would show the same relationships but allows nodes to move , the viewer cannot directly compare node positions across views. The circular layout here gives every node a fixed, readable position with a labeled arc. A matrix view (heatmap of all pairs) would be more precise for exact value comparison but requires the viewer to trace rows and columns mentally , the chord diagram makes the relationship pattern immediately visual without any matrix traversal.

A hub node in this chart is one whose arc is the starting point for many thick, dark chords. OCHA and UNHCR are visually dense because their arcs originate the strongest chords , thick walnut and obsidian lines radiate across the circle. Government Donors and Local NGOs show thinner chords, indicating weaker or fewer coordination relationships. This hub pattern is impossible to see in a table and requires significant computation to extract from a matrix view.

Paste this into Claude Code to generate a working version of this chart, plus its data file. The result will not be a perfect replica , the goal is that the reader can run the prompt, get a chart of this type, and read its source. Generate a complete, self-contained chord diagram in D3 v7. Two files:

The ideas in this chapter didn't appear from nowhere. Augustus De Morgan drew circular relational diagrams in Formal Logic (1847) , points arranged around a ring, lines drawn between them whenever a logical relation held. He was reasoning about syllogisms, not about gene expression or trade flows, but the layout choice was the same one Circos would make 162 years later: a ring is the most legible way to show many-to-many connections between a fixed set of entities. Augustus De Morgan, circa 1860.

The ideas in this chapter didn't appear from nowhere. Augustus De Morgan drew circular relational diagrams in Formal Logic (1847) , points arranged around a ring, lines drawn between them whenever a logical relation held. He was reasoning about syllogisms, not about gene expression or trade flows, but the layout choice was the same one Circos would make 162 years later: a ring is the most legible way to show many-to-many connections between a fixed set of entities. Augustus De Morgan, circa 1860.