After Brown University economics professor Roberto Serrano moved a midterm to a take-home format, grades spiked implausibly — 40 of 86 students scored a perfect mark — exposing how easily generative AI evades detection on remote assessments.
96
Take-home midterm class average (Spring 2026)
40 of 86
Students scoring a perfect mark on the take-home midterm (Spring 2026)
65–80
Typical class average on prior in-person midterms
48.6
Class average on the subsequent in-person, closed-book final exam (Spring 2026)
59
Students who sat the in-person final exam (of 86 enrolled) (Spring 2026)
Details
Promoter
Brown University, Department of Economics (ECON 1170)
Period
Spring 2026 semester; publicly reported June–July 2026
In spring 2026, Brown University economics professor Roberto Serrano moved the midterm exam for course ECON 1170 to a take-home, online format, after enrolment jumped to 86 students from a previous record of 30. The take-home midterm average came out at 96, far above the typical 65–80 range for prior in-person versions, with 40 of the 86 students scoring a perfect mark and many answers showing the hallmarks of ChatGPT-style output.
Results
Serrano said he suspected at least 50 students of using generative AI on the exam, and that the university was slow to open a formal investigation until the case drew public attention. When he reverted the final exam to an in-person, closed-book format, only 59 of the enrolled students sat it and the class average dropped to 48.6 — a contrast independent journalists have treated as strong circumstantial evidence of undetected AI-assisted cheating on the take-home version. Brown has not published its own official statistics; the figures come from the professor's account as corroborated by multiple news outlets.
Implementation
Indicative cost
Low (< €50k)
Time to results
Short (< 1 year)
Staffing & skills
course instructor (Prof. Roberto Serrano), university academic-integrity investigators
Conditions for success
closed-book/in-person format or verified proctoring for high-stakes take-home exams
prompt formal investigation when grade patterns look implausible
Common failure modes
take-home, unproctored format used for a high-stakes exam
slow institutional response until the case drew public attention
Commonly funded by
Own resources / municipal budget
Indicative funding routes for practices of this type — always check each programme's current calls and eligibility rules.
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Claim it —
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Data sources
Where this practice's information was retrieved from, and when.
