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Calibration curve in a essay

How to read the AI-likelihood score on your academic essay without panicking — and the part of the detector's report that actually tells you something.

Calibration curveEssayWritten by the desk

A detector that says your essay is "74% AI" has not measured anything about your work. It has measured how predictable the surface of the text is, run that through a model, and reported the result. Whether that 74% is meaningful depends entirely on the detector's calibration curve.

What a calibration curve is

It's a plot, built on thousands of labelled examples, comparing the detector's stated confidence to the true rate of correctness. A well-calibrated detector hugs the diagonal — when it says 70%, it's right about 70% of the time. A curve that bows away from the diagonal is the visual signature of a detector that bluffs: it states high confidence on examples it is actually unsure about.

Three things to do with your score

  1. Treat it as evidence, not a verdict. A confident essayist reads the score the way they'd read a peer-review comment — as a signal to look at the passage more carefully.
  2. Look at the per-sentence breakdown, not just the overall number. snizzly's detector tells you which specific sentences pulled the score up. The overall number averages those — the sentence-level view is where the editing happens.
  3. Re-score after edits, and watch the direction of travel. A single number means little; a number that moved from 81 to 22 after you replaced the generic openings with specific ones tells you something real.

Before

[Detector score: 81% AI] In conclusion, the literature presents compelling evidence that suggests a significant correlation. Furthermore, additional research is needed to fully explore the implications of these findings.

After

[Detector score: 22% AI] The pattern holds across all three studies, though the effect size in Andersson (2019) is half what the earlier papers reported — possibly because the post-2015 sample includes the policy change. Worth following up.

The before paragraph has flat hedges, generic connectives and no specifics. The after commits to a claim, attributes a counter-result, and offers one explanation. The score moves because the writing genuinely changed.
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