Academic Reading
Academic Reading #6: Read Figures, Units, and Uncertainty
Read Figures, Units, and Uncertainty
A graph is an argument that you must inspect.
Figures can make a paper easier to understand, but they can also be easy to misread. Begin with what was measured, how it was measured, and what the labels mean.
Swipe across the diagram to read every label.
Read the caption before the pattern
A multi-panel figure may combine a photograph, a diagram, a measurement, and a model. Read the caption and identify each panel. Then inspect the axes, units, legend, and scale. A logarithmic axis uses multiplicative steps; equal spacing does not mean equal numerical change. A microscope image also needs a scale bar.
Always ask “a percentage of what?”
A percentage needs a denominator. Percentage by number and percentage by mass answer different questions. A collection can contain many tiny objects but most of its mass may come from a few large objects. Before saying that one category dominates, state the measure. This habit is just as useful for energy efficiency, error rates, and survey results.
Separate observation from explanation
First describe a visible pattern without explaining its cause. Next read the Results paragraph connected to that figure. Finally, check the Discussion for the proposed explanation. In your notes, use separate lines for “what the data show” and “what the authors think it means.” Do not invent a mechanism because a line rises.
Keep uncertainty attached
Error bars and shaded bands can represent different things, such as variation among observations or uncertainty in an estimate. Read the definition. Check the sample size and whether measurements are independent. Overlapping bars alone do not settle statistical significance. A small p-value does not tell you whether the effect is large or useful; examine the effect size, design, and uncertainty together.
Your reading task
In the original teaching chart below, small objects are 90% of the count but 20% of the mass. Write two accurate sentences. Then explain why “90% of the mass is small objects” is wrong.
Open the model answer or self-check
“Small objects account for 90% of the object count.” “They account for 20% of the total mass.” The incorrect sentence exchanges the denominators. These chart values are invented for practice and are not the ocean-plastic paper’s data.
Read the source: abstract and Table 1
Write the two published microplastic percentages with their correct denominators. Then locate the size definitions in the paper. Connect this skill to Academic Presentation #4 on explaining graphs.
Open the learning resource →All eight reading lessons
- Read with a Purpose, Not a Dictionary
- Find the Shape of a Research Paper
- Read Titles and Abstracts as a Research Story
- Follow the Argument and Its Signposts
- Unpack Long Sentences and Technical Words
- Read Figures, Units, and Uncertainty (this lesson)
- Judge Claims, Methods, and Limits
- Turn Reading into Notes, Questions, and a Short Talk
Built for Japanese science and engineering students. Paper spotlights are teaching paraphrases, not quotations. Practice sentences and diagrams are original teaching material. Read the linked original before citing a scientific claim. Continue with Academic Listening or Academic Presentation.
同じコースの他のレッスン
Academic Reading中級 / Intermediate
Academic Reading #4: Follow the Argument and Its Signposts
Recognise background, gaps, contributions, and logical connections in an introduction.
Academic Reading中級 / Intermediate
Academic Reading #5: Unpack Long Sentences and Technical Words
Break dense sentences into meaningful groups and learn technical vocabulary in context.
Academic Reading中級 / Intermediate
Academic Reading #7: Judge Claims, Methods, and Limits
Distinguish association from causation and preserve the limits of a scientific claim.