Views sharing one screen need a statable relationship to each other, not just physical proximity

What it is

Views sharing one screen must have a statable data relationship: different facets of the same data (a total's trend and its composition), sibling branches of one level, or the parent-child of overview and detail. With the relationship explicit, multiple views read as the several dials of one instrument; without it, they are posters pinned to the same wall.

Why it happens

The data relationship is the precondition of every coordination mechanism (the core instruments of the interaction family): linking and brushing propagate across views only because the views show different projections of the same records; drill-down moves from overview to detail only because the two are levels of one metric. The relationship also fixes layout semantics: vertical order implies hierarchy (overview above), side-by-side implies comparison (same-period contrast), and when the relationship matches the layout semantics, users read the dashboard's structure by spatial intuition. The direct symptom of an unstatable relationship is the user unable to answer "what do these two charts have to do with each other."

Where it stops holding

A data relationship does not exclude views differing in time — "this month" and "last month" differ in data but relate explicitly (same metric, different periods); the relationship needs stating at the metric-and-dimension level. Nor must every relation be strongly coupled: a dashboard may carry a fully independent reference block, but it should be visually segregated (grouped, whitespace) and clearly labelled as background material so it is not misread as part of the main system. Multi-source dashboards (business data plus system monitoring) are legitimate, but grouping and labelling must make data ownership unmistakable.

Applying it

• Draw a view-relationship diagram in the dashboard's design document: which views share data, what the hierarchy is, how linking runs.
• Organise layout by relationship: hierarchy top to bottom, comparison side by side, independent material visually set apart.
• Verification: ask users to state the relationship between any two views; inability or error means the relationship is unreadable — add linking, labelling, or re-layout.

Related

• Same group: U7.01.1 Multiple views divide distinct questions · U7.01.3 Stacking unrelated views scatters attention
• Nearby: U6.02.1 A selection in one view should sync to related views · U6.05.1 Drill-down descends a predefined hierarchy from summary to detail
• Search terms: coordinated views · dashboard information architecture · view relationship