03 · What You Need to Know
What Must Be Verified in an AI-Generated Research Figure?
Why Can AI-Generated Figures Contain Incorrect Values?
Generative AI systems can produce convincing visualizations without reliably preserving every numerical relationship in the source material.
Errors may occur when a language model interprets a table, generates plotting code, calculates summary statistics, or produces an image directly from a textual description.
For example, an AI system might confuse standard deviations with standard errors, assign values to the wrong categories, omit observations, or use an incorrect denominator when calculating percentages.
Some failures are computational. Others arise because the AI has misunderstood what a variable represents or how the researcher intends the data to be summarized.
The problem is closely related to the possibility that AI can produce graphs that look correct while plotting incorrect values.
What Does It Mean to Verify Every Value?
Verification means establishing a traceable relationship between the information displayed in a figure and the authoritative data or analytical results from which it was derived.
This includes more than the numbers printed beside graphical elements.
| Figure Element |
What to Verify |
Authoritative Source |
| Bar height |
Correct value and group assignment |
Validated summary table or analysis output |
| Scatterplot point |
Correct paired coordinates |
Analysis dataset |
| Line graph |
Correct values, sequence, and time points |
Time-series data or analytical output |
| Percentage |
Correct numerator, denominator, and calculation |
Source counts and verified computation |
| Error bar |
Correct estimate, uncertainty measure, and endpoints |
Statistical analysis output |
| Regression line |
Correct fitted values and model specification |
Validated model output |
| Annotation |
Correct p-value, effect size, or other reported statistic |
Statistical results table |
| Category label |
Correct association between label and plotted values |
Data dictionary or analysis dataset |
For a complex figure, the verification unit may be an entire data series or plotted coordinate rather than an isolated printed number. The objective is to ensure that every meaningful graphical mark is supported by the intended source.
Which Data Should Be Treated as the Source of Truth?
The authoritative source depends on the figure's purpose.
If a scatterplot displays individual observations, the relevant source may be the cleaned analysis dataset. If a bar chart displays model-adjusted means, the source should be the validated statistical output rather than simple averages calculated from the raw observations.
For a regression figure, the appropriate reference may include the model specification, estimated coefficients, predictions, and uncertainty intervals.
Researchers should distinguish among raw data, cleaned data, transformed variables, analytical results, and plotting data.
Source data
The original or appropriately processed observations used in the analysis.
Analytical output
Validated estimates, summaries, and statistical results produced from the data.
Plotting data
The exact values and coordinates supplied to the visualization software.
Rendered figure
The final visual representation of those plotting values, including scales, labels, and graphical elements.
A reliable audit follows the chain from the appropriate authoritative source through the plotting data to the rendered figure.
Why Is Checking the AI's Input Table Not Enough?
An AI system may receive a correct table and still produce an incorrect graph.
For instance, it might generate plotting code that selects the wrong column, sorts categories unexpectedly, or transforms values using an inappropriate calculation.
Even when the plotting code is correct, later modifications to axis limits, labels, or exported images may introduce discrepancies.
Verification should therefore examine the actual data used by the plotting process, not merely the information originally supplied in the prompt.
How Do You Verify Means and Other Summary Statistics?
When a figure displays summary statistics, independently calculate or retrieve the corresponding values from a validated analysis.
For example, a graph displaying group means should be checked against the intended grouping variable, inclusion criteria, missing-data treatment, and statistical definition of the mean.
If the plotted values are weighted means, estimated marginal means, or other model-derived quantities, ordinary arithmetic averages are not appropriate substitutes.
The verification process must reproduce the statistic actually reported rather than calculate a different statistic that happens to have a similar name.
How Do You Verify Percentages?
Percentages require particular care because an incorrect denominator can produce a plausible but misleading result.
Suppose a study includes 100 participants, but only 60 answered a particular question. Using 100 as the denominator would produce 42%, while using the 60 valid responses produces 70%.
Neither denominator should be selected merely because it makes the result look more favorable. The appropriate choice depends on the research question and the analysis plan.
How Do You Verify Error Bars and Confidence Intervals?
Error bars may represent standard deviations, standard errors, confidence intervals, or other uncertainty measures. These quantities have different meanings.
Researchers should verify the intended uncertainty statistic, its calculation, and its graphical representation.
For a confidence interval, the plotted endpoints should match the validated analytical output. Do not assume that every interval is symmetric around the estimate or that every 95% confidence interval can be reproduced using a simple normal approximation.
Some estimates use asymmetric intervals, transformed scales, bootstrap procedures, or model-specific calculations.
Nature's figure guidance requires statistical information and error bars to be defined clearly. The underlying principle is that readers must be able to understand what the graphical uncertainty represents.
How Do You Verify Scatterplots and Line Graphs?
For scatterplots, confirm that each x-coordinate is paired with the correct y-coordinate. Independent verification of the two columns is insufficient if their row alignment has been altered.
For line graphs, check the order of observations, time points, missing values, and whether the software has connected points that should remain separate.
Special attention is necessary when AI generates code that automatically sorts records, aggregates repeated observations, or interpolates missing values.
Interpolation and smoothing are not inherently inappropriate, but they should be methodologically justified and clearly distinguished from observed measurements.
How Do You Verify Regression and Model-Based Figures?
Model-based visualizations require verification of the statistical model as well as the displayed values.
A regression plot might use correct coefficients but incorrect predictor values, reference categories, or confidence intervals.
Researchers should confirm the model formula, estimation sample, variable transformations, prediction settings, and plotted estimates.
When an interaction is involved, verify that predictions correspond to the intended combinations of predictor and moderator values.
A graph can be numerically consistent with an incorrectly specified model. Therefore, verifying the plotted values does not replace validating the statistical analysis itself.
Can Automated Checks Help Verify AI-Generated Figures?
Yes. When the visualization is created from structured data and reproducible code, automated comparisons can identify many numerical discrepancies.
A verification script might compare the plotting table with a validated results table, confirm the number of plotted observations, test category assignments, and flag differences exceeding a defined numerical tolerance.
For example, a researcher could check that every group mean in the plotting dataset matches the corresponding validated mean within a specified tolerance.
However, automated checks should not be treated as infallible. If both the original calculation and the verification script use the same incorrect formula, the comparison may pass despite the underlying error.
Independent calculations, explicit expectations, and review of the analytical method remain valuable.
What About Rounding and Numerical Precision?
Displayed values may differ slightly from analytical output because of legitimate rounding.
Suppose a verified mean is 84.376. A figure label showing 84.4 may be appropriate if the reporting convention uses one decimal place.
However, rounding should be applied consistently, and the underlying plotted coordinates should not be silently replaced with rounded labels unless that is the intended representation.
Researchers should establish acceptable tolerances based on numerical precision and analytical context. A fixed tolerance suitable for examination scores may be inappropriate for very small measurements or highly precise estimates.
Can You Verify a Figure That Exists Only as an Image?
Verification is more difficult when the only available output is a flattened image.
A researcher can inspect printed labels and approximate graphical positions, but this may not establish the exact values encoded in bars, points, or curves.
Extracting coordinates from a raster image may introduce measurement uncertainty, particularly when the image has been resized or compressed.
Whenever possible, request the plotting data and editable source rather than relying exclusively on an image.
If a general-purpose image generator created the figure without a traceable data-to-graphics process, rebuilding it from validated data in statistical or visualization software is usually more defensible than attempting to certify its numerical accuracy from appearance alone.
Watch Out
Do not ask the same AI system to certify that its figure is accurate and treat its reassurance as verification. The system may repeat an incorrect interpretation or overlook the same error that produced the figure. Verification requires an authoritative reference and a check independent of the generated presentation.
How Does Figure Verification Relate to Research Reproducibility?
A reproducible figure can be regenerated from documented inputs, analytical procedures, and plotting instructions.
PLOS's Data Availability Policy explicitly includes values used to build graphs among the information needed to reproduce reported findings. Its requirements are subject to recognized legal and ethical restrictions on data sharing.
Elsevier also identifies research data availability as an important component of transparency and reproducibility, while noting that specific requirements vary across journals.
Retaining plotting datasets, code, and analytical outputs makes it easier to investigate discrepancies and regenerate figures after revisions.
Researchers should preserve appropriate records even when public sharing is restricted by confidentiality, ethics approval, or third-party data agreements.