Burrows' Delta
Definition
A computational authorship attribution metric based on the frequency distribution of the most common function words in a text; widely used in forensic linguistic studies of English and other languages.
- Type
- Authorship attribution statistic
- Input
- Frequencies of most common function words
- Field
- Forensic and computational stylometry
- Output
- A distance score between a disputed text and candidate authors
Common questions
Why does Burrows' Delta use function words instead of content words?+
Function words such as pronouns, prepositions and conjunctions are used unconsciously and stay fairly stable regardless of topic, so their frequencies track an author's habitual style rather than what the text happens to be about, making them more reliable for attribution.
What does a low Delta score mean in practice?+
A lower Delta indicates the disputed text's word-frequency profile is statistically closer to a candidate author's known writing. It ranks candidates relative to each other rather than proving authorship on its own, so it is normally used alongside other stylometric and contextual evidence.
Related terms
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- Proportion Ratio
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- Slant Drift
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