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How Pangram Works

What is a False Positive / False Negative? + Precision / Accuracy

What false positives, false negatives, precision, and accuracy mean for AI detection.

Last reviewed Jul 24, 2026

These terms describe how an AI detector can be right or wrong. They're useful for interpreting any Pangram result.

The terms

  • False positive (FP) — human-written text incorrectly flagged as AI.
  • False negative (FN) — AI-written text that the detector misses.
  • Precision — of everything flagged as AI, how much really was AI. High precision means few false positives.
  • Accuracy — how often the detector is correct overall, across both AI and human text.

Precision = TP / (TP + FP)

Accuracy = (TP + TN) / (TP + TN + FP + FN)

False Positive Rate (FPR) = FP / (FP + TN)

False Negative Rate (FNR) = FN / (FN + TP)

For Pangram's own numbers, see How precise / accurate is Pangram?