NBER: 30% of US STEM PhD abstracts show AI-generated text

Roughly 30% of PhD dissertations in science, technology, engineering and mathematics in the United States this year contained AI-generated text, according to Nature's reporting on a new National Bureau of Economic Research working paper.

The paper covers more than 226,000 STEM doctoral graduates with dissertations completed between January 2019 and May 2026. AI-generated text in dissertation abstracts first appeared in 2023 at 1.7%, rose to 18.8% in 2025, and reached 29.4% in the first five months of 2026. Mathematical and computer sciences lead at 36%. About 41% of dissertations by graduates educated in non-English-speaking countries had AI-generated abstracts, compared with 23% of dissertations by those from English-speaking countries.

The career finding is the one that will travel. Graduates whose abstracts contained AI-generated text were 17% less likely to be employed in academia than those who did not use AI, and 16% more likely to be employed in industry. The team used the AI-detection service Pangram; the authors report that 90% of the flagged AI-generated abstracts were classified by Pangram as entirely AI-generated.

"If our students are only doing half the work and they're dishing the rest to AI, do they really have the depth of understanding to be good scientists?" asks Daniel Gross, one of the paper's authors.

The working paper has not been peer reviewed. Two researchers on our Who's Who tracker posted the Nature piece in the days after it ran.