CEPD · Module 2 — Visual and information design for screens
Label units, cite sources, and don’t turn Mayer’s median d into a percentage bar.
About 16 min
Practice in the lesson player
Sorting, matching, quizzes, and the module gate stay behind a free account so scored answers are not public. The teaching notes below are the same cited curriculum.
01
A chart slide is not clip art. Production directors label the unit (%, median d, count), cite the source under the graphic, and cap bar count so mobile readers can scan. CDLA Module 2 taught Mayer’s ds — production must not display them as “70% improvement.”
02
Check | Pass? | Why
Unit on chart | Yes | Prevents d vs % confusion
Source caption | Yes | Fact-check trail
≤10 bars on mobile | Yes | Reduces extraneous load
03
Mayer (2017) reports multimedia-principle results as a median effect size, d = 1.67, from a set of experiments — not “learners improved 70%.” A bar chart labeled “% improvement” with that number is a false caption. If you show the figure, label the axis “median d,” name Mayer (2017) under the graphic, and do not convert d into a completion rate or a satisfaction score. When you do not remember the number, say so. Do not invent a percentage to make the slide look decisive.
04
Send back: Five bars, no unit, stock photo behind the plot. · “70% better learning” with no source. · Mayer’s median d drawn as a percent bar.
Ship: Axis says median d. Caption cites Mayer (2017). · Bar count fits a phone without scrolling a legend. · The decision under the chart is explicit: keep narration with the graphic, or cut it.