Scatter plots and uncertainty

Create a scientific scatter plot with error bars

Show the relationship between two measured variables while making the uncertainty and meaning of every point clear.

Hands-on example

Try this in FigureCheck

Compare a scatter plot with an error-bar plot using the supplied uncertainty column.

Opens a small synthetic dataset with a step-by-step guide in a new editable session.
Scientific scatter plot of reaction rate against temperature with vertical measurement error bars and a linear trend
Example: paired measurements with visible uncertainty, descriptive axis labels, and a restrained fitted trend.

When a scatter plot is appropriate

Use a scatter plot when every marker represents a paired X and Y observation. Do not connect points unless their order is meaningful, such as measurements collected through time or increasing concentration.

Choose axis limits that show the data without implying a stronger or weaker relationship. Starting at zero is not required for a scatter plot, but any restricted range should remain visually honest and clearly labeled.

Choose the correct uncertainty

  • Standard deviation (SD) describes the spread of observations.
  • Standard error of the mean (SEM) describes uncertainty in an estimated mean and becomes narrower as sample size increases.
  • A confidence interval gives a range produced by a stated procedure, commonly a 95% interval.

SD, SEM, and confidence intervals answer different questions. Name the quantity in the caption or legend rather than labeling every one as simply "error."

Build it in FigureCheck

  1. Select the independent measurement as X and the response as Y.
  2. Select the column containing Y uncertainty under Error bars.
  3. Use color groups only when the categories represent a real comparison.
  4. Export and inspect marker, error-bar, and label visibility at the final size.
FigureCheck Web v1.0.4 (20260805-002332) Next: Uncertainty calculations
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