Writing Style Similarity Reflects Academic Genealogy

A new study from arXiv (2608.14843v1) finds that academic advisors' writing styles are 39.9% closer in cosine distance to their students' styles than random same-field authors, based on 5,803 authors and 2,501 advisor-student pairings from the Mathematics Genealogy Project. The effect persists with academic siblings (30.4% closer across 8,360 pairs) and causes authorship attribution systems to make errors on true authors' advisors and siblings 11 times more often than chance, raising concerns about false accusations against legitimate authors.

arXiv:2608.14843v1 Announce Type: new Abstract: As authorship attribution systems are increasingly deployed to detect ghostwritten and AI-generated papers, their errors can support accusations against legitimate authors. These systems assume each author's style is their own. Researchers, however, study under advisors, and inherit their stylistic quirks. We build a corpus of arXiv authors with $\geq 2$ solo papers from the Mathematics Genealogy Project graph, giving $5{,}803$ total authors and $2{,}501$ ground-truth advisor-student pairings. Using embeddings from a fine-tuned model, advisors sit $39.9\%$ closer in cosine distance to their students than a random same-field author does. Two open encoders reproduce the effect at $12.6\%$ and $14.5\%$. \emph{Academic siblings}, two students of one advisor who may never have met, sit $30.4\%$ closer across $8{,}360$ pairs, even when they studied at different institutions. Pairs who share only an institution and a field show negligible similarity. Given a closed-set attribution task over the same corpus, the system's errors occur on the true author's advisors and academic siblings $11$ times more often than chance.