A toolkit to help your reader
How to build low-friction paths from questions, through evidence, to understandable interpretations.
The role of visualization
"What chart should I use?"
"How can I clearly convey a well-supported narrative?"
"What comparisons do I want the reader to make?"
Your purpose leads to a question, the question defines the reader task, and the reader task determines the visual construction.
Your role is important
A visualization is a guided argument, not a decoration after the analysis.
Storytelling does not mean exaggeration. It means controlling the order in which the evidence becomes understandable. You provide a path through the evidence.
Think about what your reader needs. Exploration invites investigation; explanation guides interpretation; exemplification builds intuition.
Part 1
A chart type is not a primitive object. It is a combination of marks, channels, coordinates, scales, and context.
A visualization maps variables onto properties of marks: position, length, hue, lightness, shape, area, slope, and sometimes motion.
Position on a common scale is usually easiest for quantitative comparison. Area, angle, colour intensity, and volume need more care.
Cartesian, polar, and geographic coordinates organise space differently. Changing coordinates changes what the reader can compare quickly.
Linear, percentage, relative-growth, logarithmic, temporal, categorical, and diverging scales answer different questions. Ask: what does equal visual distance mean?
Intervals, dots, ensembles, and fans communicate different uncertainty concepts. Choose the form that matches what the uncertainty means.
Titles, subtitles, labels, units, annotations, sources, sample sizes, definitions, and methods are active parts of the argument.
Part 2
Proximity, similarity, enclosure, connection, continuity, alignment, and whitespace determine what viewers treat as belonging together.
Colour and salience guide attention before conscious reasoning. Use them to guide the first comparison, then test whether the message survives colour-vision differences and grayscale.
Legends, distant labels, and unexplained symbols force the audience to decode while you want them to reason.
Based on Franconeri et al.: direct labeling and annotation often reduce memory load.
Truncated axes, log scales, area encodings, and baseline choices can be valid, but only when the reader can see what changed.
Part 3
Same data, different perspective
A table facilitates easy lookup; a scatterplot supports pattern finding. Switch between modes of visualization to see different aspects of the data..
Chart types are recurring solutions: ranking uses a common scale, time uses temporal position and connection, relationships use two quantitative positions, and flows use connection, direction, and width.
Use the visual form that matches the task: follow one trend, explain a jump, or untangle many individual patterns.
Category charts are not interchangeable. The right form depends on whether the reader needs order, paired comparison, composition, or spread.
A map is excellent when spatial pattern explains the result. If the task is ranking, a chart often beats geography.
Source: By Carter et al. in prep 2026, figure made by Casper van Elteren using Ultraplot.Flow diagrams work when the reader can follow direction and check what is conserved. They fail when every branch gets equal attention.
Part 4
Similar averages and correlations can come from very different distributions. Think about your metrics and, for example, show the x-y shape before trusting a single number.
Inspired by Anscombe-style datasets and Franconeri et al. on global statistics, comparison, and working-memory limits.
Case study — information graphic
Charles Joseph Minard’s 1869 map makes the changing scale of Napoleon’s 1812–13 Russian campaign visible at a glance. It is a classic information graphic because every encoding serves one question: what happened to the army on this journey?
Read the encodings
Read critically: the graphic pairs losses with cold; it does not, by itself, prove what caused each loss.
Titles, direct labels, annotations, highlighting, and captions implement these stages. They guide interpretation without hiding the science.
Activity - critique, redesign, and sketch
In groups: mark the question, claim, comparison, encoding, attention path, and caveat. Then make a rough first design.
The most important part: Be explicit about why we need your work. What question does it answer, and what are the consequences?
